Nanoscale solar cells that self-assemble, self-repair
The sun’s rays can be highly destructive to materials, so some of the novel solar energy systems now being developed may get less efficient as they are used. Plants deal with that problem by continually disassembling and reassembling their light-gathering molecules so they’re in effect always brand new. MIT researchers have now been able to mimic that strategy. They start with a mixture of components suspended in a soapy solution (above). They then filter out one of the components, and those that remain assemble themselves into a highly ordered series of light-harvesting, electricity-producing structures (front cover). For more details on the diagram and the research, see page 4.
M I T E n E r g y I n I T I a T I v E a u T u M n 2 0 1 0
I n T h I s I s s u E
Energy Futures
A promising lightweight battery for electric cars: New catalysts push up lagging efficiency
MIT study confirms natural gas as bridge to low-carbon future
Aiming at campus energy savings, hitting the targets
A breath of fresh air: Students explore alternatives for lab safety test
a l e t t e r f r o m t h e d i r e c t o r s
2 UpdateontheMITEnergyInitiative
r e s e a r c h r e p o r t s
4 Newphotovoltaictechnology:Nanoscalesolarcellsthatself-assemble, self-repair
8 Apromisinglightweightbatteryforelectriccars:Newcatalystspushup laggingefficiency
12 Predictingnaturalgasuse:Trends,trajectories,andtheroleofuncertainty
16 Undergroundstorageofcarbondioxide:Microbesmayhelpsealitin
18 Newinsightsintocapturingsolarenergy
r e s e a r c h n e w s
21 MITEIawardsfifthroundofseedgrantsforenergyresearch
e d u c a t i o n & c a m p u s e n e r g y a c t i v i t i e s
23 Abreathoffreshair:Studentsexplorealternativesforlabsafetytest
e d u c a t i o n
25 NamedEnergyFellows,2010–2011
26 MITEI’sundergraduateenergyresearchflourishes
27 Firstweekoncampusenergizesfreshmen
c a m p u s e n e r g y a c t i v i t i e s
29 Aimingatcampusenergysavings,hittingthetargets
o u t r e a c h
31 MITstudyconfirmsnaturalgasasbridgetolow-carbonfuture
34 MITEIreleasesreportoncriticalelementsfornewenergytechnologies
35 MITEIseminarsandcolloquia
lfee • laboratoryforenergyandtheenvironment
36 MartinFellowsexplorethechangingcoastalenvironment
o t h e r n e w s
37 DeutchnamedtoSecretaryofEnergyAdvisoryBoard
37 Herzogreceivesinternationalaward
38 MITEIExternalAdvisoryBoardmeets
m i t e i m e m b e r s
39 NewtechnologiesunveiledatEni-MITpressbriefing
39 MITEnergyFellowsSymposium
40 LatestseedgrantprojectssupportedbyMITEImembers
41 MITEIFounding,Sustaining,Associate,andAffiliatemembers
c o n t e n t s
Energy Futures ispublishedtwiceyearlybytheMITEnergyInitiative.Itreportsonresearchresultsandenergy-relatedactivitiesacrosstheInstitute.Tosubscribe,[email protected].
Copyright©2010MassachusettsInstituteofTechnology.Forpermissiontoreproducematerialinthisnewsletter,pleasecontacttheeditor.
NancyW.Stauffer,[email protected]
ISSN1942-4671(OnlineISSN1942-468X)
MIT Energy InitiativeTheMITEnergyInitiativeisdesignedtoaccelerateenergyinnovationbyintegratingtheInstitute’scutting-edgecapabilitiesinscience,engineering,management,planning,andpolicy.
MITEnergyInitiativeMassachusettsInstituteofTechnology77MassachusettsAvenue,E19-307Cambridge,MA02139-4307
617.258.8891web.mit.edu/mitei
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Printedonpapercontaining30%post-consumerrecycledcontent,withthebalancecomingfromresponsiblymanagedsources.
Energy Futures
2 | Energy Futures | MIT Energy Initiative | Autumn 2010
Update on the MIT Energy Initiative
a l e t t e r f r o m t h e d i r e c t o r s
Dear Friends,
MITEIhasjustcelebrateditsfourthbirthday.Wespentourfirstyearlayingthegroundworkandbuildingtheinfrastructureforourprogramsinresearch,education,campusenergymanagement,andpolicyoutreachandthelastthreeyearsadvancingthisagenda.NowisanopportunetimetorevisitandreflectonsomeofthechoicesmadeinstructuringMITEIandtoaddresstheopportunitiesandchallengesthatlieahead.
Fundamentally,thepathwayslaidoutforeachofthefourmissionareashaveprovedtobeveryproductive,andnewdirectionsarealsotakingshapeineacharea.ThesuccessofMITEItodatehasbeenaccomplishedthroughtheeffortsofanextraordinarygroupoffaculty,students,staff,private-andpublic-sectorpartners,alumni,andfriends.
Akeyinitialcommitmentwasadvancingenergyresearchbothforinnovationssupportingtoday’senergysystemsandfortransformational“gamechangers.”Thistwo-trackapproachwasdeemedessentialforreachingalow-carbonandsecureenergyfutureinthe2006MITEnergyResearchCouncilplanningreport,thedocumentthathasguidedourfirstfouryearsofoperation.
Thisjudgmenthasbeenreinforcedbythediminishinglikelihoodthatachargeoncarbondioxideemissionswillbeimplementeddomesticallyanytimesoon.Internationally,expectationsfortheclimatemeetinginCancunareconsiderablylessthantheywerefortheprecedingmeetinginCopenhagen.
Theinterplayofinnovationandtrans-formationishighlightedbyresultsfrom
therecentMITFutureofNaturalGasstudy,summarizedonpage31.Inthenearterm,aneconomicallyefficientpathtoalow-carbonfuturewilllikelybedrivenprincipallybythecombinationofreducedenergydemand,notablythroughimprovedbuildingsandincreasedvehicleefficiency,andthesubstitutionofnaturalgasforcoal.Thispathwaywillbesupplementedbygrowthinnuclearpowerandrenewabletechnologies.Thecombinationofefficiencyandnaturalgasformsthebridgetoalow-orzero-carbonfuture.
Toensurethatthisisa“bridgetosomewhere,”game-changing“zero-carbon”technologiesmustscaleupindramaticfashioninjustacoupleofdecades.ResearcharticlesinthiseditionofEnergy Futures delveintosomeofMIT’sworkonthesegame-changingoptions,includingsolarenergy(page4),vehiclebatterytechnology(page8),andcarbondioxidesequestra-tion(page16).ThisworkissupportedbyMITEIindustrypartners,eitherindividuallythroughsponsoredresearchorcollectivelythroughtheearly-stageseedgrantprogram.Thelaggingprogressontheenergypolicyfrontheightenstheimportanceofloweringthecostoftheseandothertransformationaltechnologiesandrapidlymovingthemintothemarket.
MITEI’sindustry-ledstrategyhasyieldedastronginnovationandtransformationresearchportfolioalignedwithbothfacultyinterestsandcompanystrategicdirections.TheprogramsofourearliestFoundingmembers,BPandEni,haveemphasizedsolidsconversionandsolarfrontiers,respectively.Whilethatworkcontinues,bothcollaborationsarealsoleadingtodeepeningstrategicpartnershipsinnewareas.Similarprogresshasbeenmadewithour
earliestSustainingmembers.Atthesametime,newpartnershipscontinuetoform.InOctober,wewerepleasedtoannouncethatShellhadjoinedtheInitiativeasitsnewestFoundingmember(seephotoatright).
Anewdirectionisalsotakinghold,namely,substantialmultiyearfederalprograms.Overthelasttwoyears,theUSDepartmentofEnergy(DOE)hasplacedrenewedemphasisonenergyscienceandtechnologyprogramsthataresustainedandcompetitivelyawarded.Theseprogramsarecomplementarytoourindustry-supportedprogramsandareopeningupnewopportunitiesforMITEIandforMIT.MIT’ssuccessintheEnergyFrontierResearchCenterandtheAdvancedResearchProjectsAgency-Energy(ARPA-E)competitionshasbeenchronicledinpreviouseditionsofEnergy Futures.
WehavealsoassumedakeyroleintheDOE-fundedNuclearEnergyInnovationHub,ledbyOakRidgeNationalLaboratory.Thishubisdedicatedtoprovidingandemployingnewpetascalesimulationtoolstoadvancelightwaternuclearreactortechnology.Thiseffortisanexcellentexampleofinnovationfocusingontoday’senergysystems:wewillbeusingfrontiermodelingandsimulationcapabilitiestoimprovethenucleartechnologythatwillalmostcertainlydominateinthenextseveraldecades.
MITEI’sinitialfocusontheeducationfrontwasoncreatingnewcurriculumoptionsforundergraduates.UnderthecontinuingleadershipofProfessorsVladimirBulovic(ElectricalEngineeringandComputerScience)andDonaldLessard(Management)andthestrongsupportoftheMITEIEducationOffice
Autumn 2010 | MIT Energy Initiative | Energy Futures | 3
a l e t t e r f r o m t h e d i r e c t o r s
ledbyDr.AmandaGraham,thisgoalisbeingrealizedinlargepartthroughthecreationofanenergyminorprogramandcurricularofferingstosupportit.
Newdevelopmentswillincludeproject-basedsubjectsanddisseminationofnewenergycoursesthroughOpen-CourseWare.MITEIisalsoincreasingitsparticipationinandsupportfortheUndergraduateResearchOpportunitiesProgram(UROP—page26)andtheFreshmanPre-OrientationProgram(FPOP—page27).
Thecampusenergymanagementprogramissimilarlycomingintofullstride,consistentwithMITEI’soriginalvision.ThecombinedstrengthsofProfessorLeonGlicksman(ArchitectureandMechanicalEngineering)andMITExecutiveVicePresidentandTreasurerTheresaStonehavebeenessentialingreeningtheMITcampus.Studentengagementishigh,andannualsavingsfromcampusenergyprojectswillreachwellover$3millionbytheendof2010,accordingtotheMITDepartmentofFacilities.Thecollabora-tionwithNSTARwillreducecampuselectricityuseby15%overthreeyears.Inaddition,MITwasthefirstuniversityinvitedtojoinDOE’snewGlobalSuperiorEnergyPerformancePartner-ship,abuildingenergymanagementcertificationprogram(pages29–30).
Finally,MITEIhasbeenvigorouslypursuingitscommitmenttopolicy
geraldschotman(right),chieftechnologyofficer,royaldutchshell,signsanagreementwithmitpresidentsusanhockfieldtocollaborateonresearchanddevelopmentofhigh-value,sustainabletechnologiesdesignedtodriveinnovationinenergydelivery.undertheagreement,signedoctober13,2010,shellwillprovide$25milliontothemitenergyinitiative(mitei)forresearchandcollabora-tion.beginningthisyear,theresearchpartnershipwillfundasuiteofprojectsat$5millionperyearforthecomingfiveyears.theprojectswillfocusonadvancedmodeling,earthscience,biofuels,nanotechnology,andcarbonmanagement.theagreementestablishesshellasafoundingmemberofmitei,anextensionofthecollaborativeprojectsshellhasbeenconductingwithmitinavarietyofbasicandappliedresearchareassince2002.
Phot
os: J
ustin
Kni
ght
mitei’sresearch,education,campusenergy,andoutreachprogramsarespearheadedbyprofessorernestJ.moniz,director(right),andprofessorrobertc.armstrong,deputydirector.
outreach.Thepaceofourin-depthmultidisciplinarystudiesonthefutureoflow-carbontechnologypathways—startedin2003withnuclearpower—hasquickened.Inthelastseveralyears,studieshaveexaminedthefutureofcoal,geothermal,naturalgas,nuclearfuelcycles,solarenergy,andtheelectricgrid.Thesestudies—somecompletedandothersstillunderway—havedrawnontheexpertiseof40MITfacultyandseniorresearchersandacomparablenumberofgraduatestudentsandpostdocs.ThestudiescontinuetohavepolicyimpactsandarenowsupplementedbyanAssociatemember-supportedsymposiumseriesthatfocusesonmorespecificandtimelytopicsinneedoftechnicallygroundeddiscussion.
Inshort,wehavebuiltastrongfoundationthatcanaccommodatenewinitiativesineachofMITEI’sfourmissionareas.Inourfifthyear,wewillrevisittheMITEIroadmapinconsultationwithourmanyparticipantsandfriends.Withthecontinuingcontributionofsomanytalentedfaculty,students,andstaff,wefeelconfidentthat“phase2”willsustainMIT’sleadingroleindevelopingcriticalenergysolutions.Wewelcomeyourinvolvementandinputinthedaysahead.
Sincerely,
Professor Ernest J. MonizMITEIDirector
Professor Robert C. ArmstrongMITEIDeputyDirector
November2010
4 | Energy Futures | MIT Energy Initiative | Autumn 2010
r e s e a r c h r e p o r t s
New photovoltaic technology
Nanoscale solar cells that self-assemble, self-repair
Plants are good at doing what scientists and engineers have been
struggling to do for decades: converting sunlight into stored energy,
and doing so reliably day after day, year after year. Now some MIT
scientists have succeeded in mimicking a key aspect of that process.
One of the problems with harvesting sunlight is that the sun’s rays can
be highly destructive to many materials. Sunlight leads to a gradual
degradation of many systems developed to harness it. But plants have
Above: Professor Michael Strano (center) with postdoctoral researcher Moon-Ho Ham (left) and graduate student Ardemis Boghossian, all of the Department of Chemical Engineering.
Photo: Justin Knight
Autumn 2010 | MIT Energy Initiative | Energy Futures | 5
r e s e a r c h r e p o r t s
adoptedaninterestingstrategytoaddressthisissue:Theyconstantlybreakdowntheirlight-capturingmoleculesandreassemblethemfromscratch,sothebasicstructuresthatcapturethesun’senergyare,ineffect,alwaysbrandnew.
ThatprocesshasnowbeenimitatedbyMichaelStrano,theCharlesandHildaRoddeyAssociateProfessorofChemicalEngineering,andhisteamofgraduatestudentsandotherresearch-ers.Theyhavecreatedanovelsetofself-assemblingmoleculesthatcanturnsunlightintoelectricity;themoleculescanberepeatedlybrokendownandthenreassembledquickly,justbyaddingorremovinganadditionalsolution.
Stranosaystheideafirstoccurredtohimwhenhewasreadingaboutplantbiology.“Iwasreallyimpressedbyhowplantcellshavethisextremelyefficientrepairmechanism,”hesays.Infullsummersunlight,“aleafonatreeisrecyclingitsproteinsaboutevery45minutes,eventhoughyoumightthinkofitasastaticphotocell.”
OneofStrano’slong-termresearchgoalshasbeentofindwaystoimitateprinciplesfoundinnatureusingnanocomponents.Inthecaseofthemoleculesusedforphotosynthesisinplants,thereactiveformofoxygenproducedbysunlightcausestheproteinstofailinaverypreciseway.AsStranodescribesit,theoxygen“unsnapsatetherthatkeepstheproteintogether,”butthesameproteinsarequicklyreassembledtorestarttheprocess.
Thisactionalltakesplaceinsidetinycapsulescalledchloroplaststhatresideinsideeveryplantcell—andwhichiswherephotosynthesishappens.Thechloroplastis“anamazingmachine,”
Stranosays.“Theyareremarkableenginesthatconsumecarbondioxideanduselighttoproduceglucose,”achemicalthatprovidesenergyformetabolism.
Toimitatethatprocess,Stranoandhisteamproducedsyntheticmolecules
calledphospholipidsthatformdisks;thesedisksprovidestructuralsupportforothermoleculesthatactuallyrespondtolight,instructurescalledreactioncenters,whichreleaseelectronswhenstruckbyparticlesoflight.Thedisks,carryingthereactioncenters,areinasolutionwheretheyattach
“We’rebasicallyimitatingtricksthatnaturehasdiscovered
overmillionsofyears”—inparticular,“reversibility,the
abilitytobreakapartandreassemble.”
— Professor Michael Strano
Phot
o: P
atric
k Gi
llool
y, M
IT
thisproof-of-conceptversionofthephotoelectrochemicalcell,whichwasusedforlaboratorytests,containsaphotoactivesolutionmadeupofamixofself-assemblingmolecules(intheglasscylinderheldinplacebythemetalclamp)withtwoelectrodesprotrudingfromthetop,onemadeofplatinum(thebarewire)andtheotherofsilver(intheglasstube).
6 | Energy Futures | MIT Energy Initiative | Autumn 2010
R E S E A R C H R E P O R T S
themselves spontaneously to carbon nanotubes—wire-like hollow tubes of carbon atoms that are a few billionths of a meter thick, yet stronger than steel and capable of conducting electricity a thousand times better than copper. The nanotubes hold the phospholipid disks in a uniform alignment so that the reaction centers can all be exposed to sunlight at once, and they also act as wires to collect and channel the flow of electrons knocked loose by the reactive molecules.
The system Strano’s team produced is made up of seven different compounds, including the carbon nanotubes, the phospholipids, and the proteins that make up the reaction centers, which under the right conditions spontane-ously assemble themselves into a light-harvesting structure that produces an electric current. Strano says he believes this sets a record for the complexity of a self-assembling system. When a surfactant—similar in principle to the chemicals that BP has sprayed into the Gulf of Mexico to break apart oil—is added to the mix, the seven
components all come apart and form a soapy solution. Then, when the researchers removed the surfactant by pushing the solution through a membrane, the compounds spontane-ously assembled once again into a perfectly formed, rejuvenated photocell.
“We’re basically imitating tricks that nature has discovered over millions of years”—in particular, “reversibility, the ability to break apart and reassemble,” Strano says. The team, which included postdoctoral researcher Moon-Ho Ham and graduate student Ardemis
Schematic of decomposition and self-assembly of nanoscale solar cells
Photosyntheticreaction center
Sodium cholate(surfactant)
Sodium cholate(surfactant)
Phospholipids suspended in surfactant
Carbon nanotube
Membranescaffold protein
Membranescaffold protein
Removal of surfactant
Addition of surfactant
Autumn 2010 | MIT Energy Initiative | Energy Futures | 7
R E S E A R C H R E P O R T S
Boghossian, both of the Department of Chemical Engineering, came up with the system based on a theoretical analysis, but then decided to build a prototype cell to test it out. They ran the cell through repeated cycles of assembly and disassembly over a 14-hour period, with no loss of efficiency.
Strano says that in devising novel systems for generating electricity from light, researchers don’t often study how the systems change over time. For conventional silicon-based photovol-taic cells, there is little degradation,
but with many new systems being developed—either for lower cost, higher efficiency, flexibility, or other improved characteristics—the degradation can be very significant. “Often people see, over 60 hours, the efficiency falling to 10% of what you initially saw,” he says.
The individual reactions of these new molecular structures in converting sunlight are about 40% efficient, or about double the efficiency of today’s best solar cells. Theoretically, the efficiency of the structures could be close to 100%, he says. But in the initial
work, the concentration of the structures in the solution was low, so the overall efficiency of the device—the amount of electricity produced for a given surface area—was also very low. They are working now to find ways to greatly increase the concentration.
• • •
By David L. Chandler, MIT News Office
A grant from Eni S.p.A., under the Eni-MIT Solar Frontiers Center of the MIT Energy Initiative, supported work relating to photoelectrochemical cell regeneration, including design and fabrication. A grant from the US Department of Energy supported the spectroscopy and analytical chemistry of complexes in this work. Moon-Ho Ham received support from the Korea Research Foundation Grant funded by the Korean Government. Further information can be found in:
M.-H. Ham, J. Choi, A. Boghossian, E. Jeng, R. Graff, D. Heller, A. Chang, A. Mattis, T. Bayburt, Y. Grinkova, A. Zeiger, K. Van Vliet, E. Hobbie, S. Sligar, C. Wraight, and M. Strano. “Photoelectrochemical complexes for solar energy conversion that chemically and autonomously regenerate.” Nature Chemistry. Published online: 05 September 2010, doi:10.1038/nchem.822.
The self-assembly process involves carbon nanotubes and photosynthetic reaction centers and occurs when a surfactant—here, sodium cholate—is removed. Filtering out the surfactant from the starting mixture induces spontaneous self-assembly of synthetic molecules called phospholipids plus membrane scaffold proteins to form phospholipid disks. These disks provide structural support for reaction centers, which release electrons when struck by light. The disks carrying the reaction centers attach themselves spontaneously to carbon nanotubes, which are suspended in an aqueous solution. The resulting highly ordered structure is shown in the right-hand panel. Addition of the surfactant sodium cholate completely decomposes the structure back into the individual components in the initial mixture (left-hand panel).
Phospholipid disk
Removal of surfactant
Addition of surfactant
Carbon nanotubePhotosynthetic
reaction center
Diag
ram
: Ard
emis
Bog
hoss
ian
G, M
IT
8 | Energy Futures | MIT Energy Initiative | Autumn 2010
r e s e a r c h r e p o r t s
A promising lightweight battery for electric cars
New catalysts push up lagging efficiency
If electric cars are to provide the range that drivers demand, they need
batteries that can deliver lots more energy, pound for pound, than
today’s best lithium-ion batteries can. Lithium-air batteries could—in
theory—meet that challenge, but while they are far lighter than their
lithium-ion cousins, they are not nearly as efficient.
MIT researchers have now demonstrated significant gains on that
front. Using specially designed catalysts, they have made lithium-air
Photo: Justin Knight
Above: Professor Yang Shao-Horn (center) of mechanical engineering and materials science and engineering, with graduate students Yi-Chun Lu (right) of materials science and engineering and Koffi Pierre Claver Yao of mechanical engineering.
Autumn 2010 | MIT Energy Initiative | Energy Futures | 9
r e s e a r c h r e p o r t s
batterieswithunprecedentedefficiency,meaningthatmoreoftheenergyputinduringchargingcomesoutasusefulelectricityduringdischarging.Lessenergyislostateachrecharge—anadvancethataddressesoneofthemajorstumblingblockswiththispromisingtechnology.
Thoseresultsarejustafirstindicationofwhatcatalystscandofortheperformanceofthelithium-airbattery,accordingtoYangShao-Horn,directoroftheresearchandassociateprofessorofmechanicalengineeringandmateri-alsscienceandengineering.Shepredictsthatevenhigherefficiencieswillcome.
Whileothergroupsareworkingonlithium-airbatteries,sheandherteaminMIT’sElectrochemicalEnergyLaboratoryarethefirsttoperformfundamentalstudiesofcatalyststhatwillpromotekeyelectrochemicalreactionsinthesebatteries.“Thatmakesthisafunareaforustoworkin,”saysShao-Horn.“Everyexperimentislikeadiscoveryforusbecausethere’snopreviousexperimentaldatatoreferenceortolookat.”
Shao-Hornstressesthatdevelopmentofapracticallithium-airbatteryisinitsveryearlystages.“Therearestillmanyscienceandengineeringchallengestobeovercome,”shesays.Butalreadyherteam’sresultsaresignificant—andinsomecasesunexpected.
A lightweight technology
Understandingthepromisesandproblemsoflithium-airbatteriesrequiresunderstandinghowtheywork.Alithium-airbatteryconsistsoftwoelectrodes—alithiumelectrodeandanairelectrodemadeofcarbon—withanelectrolytebetweenthem.Asthe
batteryischargedanddischarged,lithiumions(positivelycharged)andelectrons(negativelycharged)shuttlebackandforthbetweenthetwoelectrodes.
Thediagramaboveshowswhathappensasthebatteryisdischarged.Electrons(e-)travelfromthelithiumelectrodetotheairelectrodethroughanoutsidecircuit,poweringadevice(thelightbulb)alongtheway.Lithiumions(Li+)makethesamejourneythroughtheelectrolyte.Attheairelectrode(showninthedetailedview),theelectronscombinewiththelithiumionsandoxygen(O2)fromtheairtoformlithiumoxide(LixO2).
Torechargethebattery,anoutsideelectricalsupplyforcesthelithiumoxidetodecompose,releasingoxygen
totheatmosphereandsendingthelithiumionsandelectronsbacktothelithiumelectrode,andthesystemisreset.Theprocessofmakingandbreakingthelithiumoxidethusallowsthebatterytogenerateelectricityandtoberecharged.
Inthisdesign,theairelectrodeconsistsofacarbon“skeleton”thatmustbothconductelectronsandprovideemptyspaceforstoringthelithiumoxide,whichisasolid.(Oxygendoesnotneedtobestored;itcomesfromtheatmos-phere.)Asaresult,fully60%oftheairelectrodeisemptyspace,makingitfarlighterthantheheavy,solidelectrodeinalithium-ionbattery.Thelithium-airbatterycanthereforedelivermoreenergyperunitweight—ameasurecalledenergydensity.Shao-Hornandherteamprojecttheenergydensityof
Processes on a lithium-air battery during discharge
whenalithium-airbatteryisdischarged,positivelychargedlithiumions(li+)movefromthelithiumelectrodethroughtheelectrolytetotheairelectrode,whilenegativelychargedelectrons(e-)travelthroughanexternalcircuit,poweringadevice(thelightbulb)alongtheway.thelithiumionsandelectronsplusoxygen(o2)fromairreacttoformlithiumoxide(lixo2),asolidthatsettlesinopenspacesamongthecarbonnanoparticlesintheairelectrode.duringcharging,thelithiumoxidebreaksapart,thethreereactantsgobackwheretheycamefrom,andthesystemisreset.
Li+Carbonnanoparticle
O2
CarbonnanoparticleLithium
electrodeAirelectrode
Electrolyte
Catalyst
e-
Diag
ram
: Eva
Mut
oro,
MIT
10 | Energy Futures | MIT Energy Initiative | Autumn 2010
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lithium-airbatteriesat1,000watt-hoursperkilogram—significantlyhigherthanthe200watt-hoursperkilogramofstate-of-the-artlithiumionbatteriesnowusedinlaptopcomputersandcellphones.
“Withthatkindofenergydensity,thelithium-airbatteryisapotentialtechnologyforelectricvehicles,”saysShao-Horn.Butthereareproblemswiththebattery.Oneislow“round-tripefficiency”duringdischargingandcharging.Whenthebatteryisdischarg-ing,energycomesoutatabout2.7volts.Butchargingituprequiresputtingin4volts.Theround-tripefficiencyisthusabout67%.“Thatmeansthateachtimeyouchargeanddischargeyourelectriccar,youlose
aboutathirdoftheenergyyouputin,”Shao-Hornsays.Instate-of-the-artbatteries,round-tripefficiencyistypically90–95%,puttingenergylossatjust5–10%.
Toimproveefficiency,Shao-Hornandherteamhavebeentryingtospeedupthelithiumoxidereactionsontheairelectrode.Theirgoal:tofindcatalyststhatwillencouragelithiumoxidetoformasthebatterydischargesandtodecomposeasthebatterycharges.Theresultwillbehighervoltagecomingoutandlowervoltagegoingin.
Theirworktodatehasfocusedonthreematerials:platinum,gold,andcarbon(asacontrolcase).Asafirsttest,theyexaminedhowthecatalystsaffectthe
ratesofthelithiumoxidereactionsonpurecatalystsurfaces.Theresultswerenotastheyexpected.Inpreviousworkwithfuelcells,platinumhadacceleratedthecombinationofhydro-genandoxygen.Inthenewexperi-ments,theplatinumdidnotencouragethelithiumandoxygentocombine.Instead,itpromotedtheoppositereaction:breakingthelithiumoxideapart.Furtherexaminationshowedthatduringlithiumoxideformation,theorganic(non-water)solventthatservesastheelectrolytecan“poison”theplatinumcatalyst.Duringlithiumoxidedestruction,thatprocessdoesnotoccurbecausethehighvoltageduringrechargingremovesthesolventpoisons.
Experimentsonthegoldsurfacealsobroughtsurprisingresults.Goldisusuallyassumedtobeapoorcatalystbecauseitisinert.Indeed,goldhadlittleimpactintheearlierfuelcellresearch.Butinthenewwork,itprovedeffectiveatpromotingtheformationoflithiumoxide.
Testing batteries
Totesttherelevanceoftheresultsonthepurecatalystsurfaces,theresearch-ersbuiltaseriesofexperimentallithium-airbatteries.Theirlithiumelectrodeispurelithiummetal(thoughforsafetyreasonsacommercialversionwoulduselithiumstoredinastablematerialsuchasgraphite).Theairelectrodeconsistsofthecarbonskel-etonmadeupoftinyparticles,eachoneabout50nanometers(nm)indiameter.Intheirnoveldesign,thesurfaceofeachcarbonparticleiscoveredwithevensmallerparticlesofthematerialbeingtested—platinum,gold,orcarbon.Thoseparticlesarejust5nmindiameter—atinysizethatmaximizestheirsurfaceareaandthereforethe
4.5
4.0
3.5
3.0
2.5
2.0
Capacity(10-3 amp hour/gram carbon)
Au = goldPt = platinum
Au
Au
PtPtAu
PtAu
Pt
Bat
tery
vo
ltag
e(v
olt
s)
0 500 1000 1500 2000
Impacts of platinum, gold, and platinum-gold catalysts on efficiency in a lithium-air battery
thesemeasurementsweretakeninexperimentallithium-airbatterieswithairelectrodescontain-ingthreecatalysts:pureplatinum(orange),puregold(green),andaplatinum-goldalloy(blue).thebottomthreecurvesshowvoltagesasthebatteriesaredischarged;thetopthreeshowvoltagesastheyarecharged.aspredicted,themeasurementswiththeplatinum-goldcatalysttrackthosewiththegoldcatalystduringdischargeandthosewiththeplatinumcatalystduringcharging.theplatinum-goldalloythusacceleratesbothofthekeyreactionsinalithium-airbatterysothatitdeliversmorevoltagewhenitisdischargedandrequireslessvoltagewhenitisrecharged.thenetresult:thehighest“round-trip”efficiencyeverreportedinalithium-airbattery.
Autumn 2010 | MIT Energy Initiative | Energy Futures | 11
r e s e a r c h r e p o r t s
numberofsitesavailableforchemicalreactionstooccur.
Theresearchersthenmeasuredthevoltageastheychargedanddischargedtheirbatteries.Thevoltagetrendsagreedwellwiththeirmeasurementsonthepurecatalystsurfaces.Indeed,accordingtoShao-Horn,theplatinum“exhibitedextraordinarilyhighactivityduringcharging.”
“Sowehadlearnedtwothingsaboutourcatalysts,”saysYi-ChunLu,agraduatestudentintheDepartmentofMaterialsScienceandEngineeringwhoistheleadauthoronthiswork.“We’dlearnedthatoncharging,platinumisbest;andondischarging,goldisbest.Butbothofthoseactivitiesoccurinthesameplace—ontheairelectrode—sowhynottrycombiningthetwocatalysts?”
Intheirnextroundofexperimentalbatteries,theymadethetinytestparticlesofaplatinum-goldalloy,workingincollaborationwithKimberlyHamad-Schifferli,associateprofessorofmechanicalandbiologicalengineer-ing,andHubertA.Gasteiger,formerlyavisitingprofessoratMITandnowaprofessoratTechnicalUniversityofMunich.Againtheytrackedthevoltagewhilecharginganddischargingthebatteries.Theyhypothesizedthatduringdischargethevoltagewiththealloywouldtrackthatmeasuredwithgoldalone,andduringchargeitwouldtrackthatmeasuredwithplatinumalone.Asshowninthediagramonpage10,theirexperimentalresultssupportedtheirhypothesis.
“Wedemonstratedthatourplatinum-goldalloyexhibitedbifunctionalcatalyticactivity,whichmeansthatondischarge,goldisdoingthework,andoncharge,platinumisdoingthework,”saysShao-Horn.“Bestofall,thebatterywiththeplatinum-goldnanoparticlesdemonstratesaround-tripefficiencyof75%—thehighestefficiencyeverreportedinalithium-airbattery.”Withfurtherwork,shebelievesherteamcanpushthatefficiencyupto85–90%.
Added benefits, future plans
Speedingupthereactionsontheairelectrodemayprovideotherbenefits.Anothershortcomingoflithium-airbatteriesisthattheytypicallycanbedischargedandchargedalimitednumberoftimes,inpartbecausethelithiumoxidetendstoclogtheairelectrode.Movingitoutmorequicklymayhelp.Also,speedingupreactionsontheairelectrodemayhelpaddressthelithium-airbattery’slow“ratecapability”—thesignificantdropintheamountofenergyitcandeliverduringrapidorprolongeddischarging.
Workwiththeirplatinumandgoldcatalystsnowfocusesoncuttingcosts.Tothatend,theyaredesigningtinyparticlesthathavethosepreciousmetalsonlyontheirsurfaces,therebyreducingtheamountneeded.Theyarealsoworkingwithother,lessexpensivematerialsthatmightprovidethesameorbetterbatteryperformance.
Ultimately,theyplantomapoutactivitytrendsonvariousmetalsurfacessotheycandevelopanunderstandingofthebasicmechanisms—thestep-by-stepbreakingandformingofchemicalbonds—involvedinthelithium-oxygen
reactions.Guidedbythatunderstand-ing,theyhopetodesigncatalystsforlithium-airbatteriesthatcouldonedaybeuptothetaskofpoweringelectricvehicles,makingpossibleafundamen-talchangeintoday’spetroleum-basedtransportationsector.
• • •
By Nancy W. Stauffer, MITEI
This research was funded by the US Depart-ment of Energy, the Materials Research Science and Engineering Centers (MRSEC) Program of the National Science Foundation, and an MIT fellowship from the Martin Family Society of Fellows for Sustainability. Further information can be found in:
Y.-C. Lu, H. Gasteiger, E. Crumlin, R. McGuire, Jr., and Y. Shao-Horn. “Electrocatalytic activity studies of select metal surfaces and implications in Li-air batteries.” Journal of the Electrochemical Society, v. 157, no. 9, 2010.
Y.-C. Lu, H. Gasteiger, M. Parent, V. Chiloyan, and Y. Shao-Horn. “The influence of catalysts on discharge and charge voltages of rechargeable Li-oxygen batteries.” Electrochemical and Solid-State Letters, v. 13, no. 6, 2010.
Y.-C. Lu, Z. Xu, H. Gasteiger, S. Chen, K. Hamad-Schifferli, and Y. Shao-Horn. “Platinum-gold nanoparticles: A highly active bifunctional electrocatalyst for rechargeable lithium-air batteries.” Journal of the American Chemical Society, v. 132, no. 35, September 8, 2010.
“Everyexperimentislikeadiscoveryforusbecausethere’s
nopreviousexperimentaldatatoreferenceortolookat.”
— Professor Yang Shao-Horn
anexperimentallithium-airbatterydevelopedandtestedatmit.theinletandoutletonthesidespermitairtoflowthrough,providingoxygenforthebattery’soperation.
Phot
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Predicting natural gas useTrends, trajectories, and the role of uncertainty
The work described here was a critical input to MIT’s TheFutureofNaturalGas, a two-year interdisciplinary examination of the role of natural gas in a carbon-constrained world out to mid-century. Key findings of that study are summarized on page 31.
TheemergenceoftechniquestoexploitvastdepositsofnaturalgasinshaleintheUShasraisedhopesthatgascanfulfillourexpandingenergyneedswhilealsoreducingemissionsbyreplacing“dirtier”fuelssuchascoalandoil.AquantitativeanalysisbyanMITteamconfirmsthatoutlook—thoughwithsomequalifications.
TheMITresultsshowthatgasusewillindeedexpand,especiallyifnewpolicymeasuresputapriceoncarbonemissions.Butifthelimitsoncarbonarestringent,eventherelativelylowemissionsofnaturalgascoulddisqualifyitfromtheenergysceneaftermid-century.Thatprojectionunder-scorestheneedforintensiveresearchtoensurethatcarbon-freealternativesarereadytotakeoverbymid-century.
Theevolutionofmarketsfornaturalgascouldalsohaveamajorimpactonitsuseandprice.Today,gasistradedonthreeseparatemarkets—NorthAmerica,Europe,andAsia.Ifatightlyintegratedglobalgasmarketdevelops,theUSwouldgainaccesstogasthatischeaperthanourdomesticresources.Asaresult,overallgasusewouldrise,benefitingtheenvironment,andconsumercostswoulddrop.Domesticproductionwouldcontinue,butby2040theUScouldbegettinghalformoreofitsenergyresourcesfromtheMiddleEastandRussia—thistime,importedgasratherthanoil.
An uncertain future
Thedevelopmentoftechnologyforproducing“shalegas”isgoodnewsonmanyfronts.Theresourceisextensive,domestic,andrelativelylowcost;anditsgreenhousegas(GHG)emissionsarelowerthanthosefromcoaloroil.Indeed,burninggasemitsabouthalfasmuchcarbondioxideasburningcoaldoes.
Sodoesthishugenaturalgasresourcehandusasolutiontoourenergyandenvironmentalworries?Canwesimplyrelyincreasinglyonnaturalgas—atleastforalongtime?It’snotsosimple,warnsateamofMITresearchers.TheroleofnaturalgasinthefutureUSenergypicturewilldependonanumberoffactors,saysHenryD.Jacoby,professorofmanage-ment.Henotesthefollowingquestions:“Howmuchgasisthere,andwhatwillitcost?Whatwillbethecostsofcompetingtechnologies?WillwehaveapolicytocontrolGHGs,andhowstrictwillitbe?Andwhatwillbethestructureoftheinternationalgasmarkets?”
Foreachofthosequestions,thereisarangeofpossibleanswers,somemorelikelythanothers,andtheirimpactsongasusewillinteract.Forexample,gasusewilldependonthecostofnaturalgasaswellasthecostsofcompetingenergysources.Thus,anycalculationofgasusemusttakeintoaccountnotonlytheuncertaintiesassociatedwiththevariouscostpredictionsbutalsohowthoseuncertaintiesinteract.
Togetaquantitativelookathowgaswillfare,Jacoby,SergeyPaltsev,principalresearchscientistintheMITEnergyInitiative,andtheircolleaguesintheMITJointProgramontheScienceandPolicyofGlobalChangeusedtheir
EmissionsPredictionandPolicyAnaly-sis(EPPA)model.ThissophisticatedmodeltrackseconomicactivityandassociatedenergyuseandGHGemissions,recognizingmultipleregionsoftheworldlinkedbytrade.Itcantakeintoaccounttechnologicalchange,resourceestimates,populationchange,andtheeffectsofspecifiedemissions-abatementpoliciesandregulations.
Upfront,theMITresearchersstressthattheiranalysescan’tprovideabsoluteanswers.“Wehavetobecarefulaboutinterpretingournumericalresults,”saysPaltsev.“Wedon’tknowpreciseanswers,butwecancapturetrendsandtrajectoriesandseethemajorimplica-tionsofpolicyandregulatorychoicesandotheruncertainfactors.”
Carefully selected assumptions
Toperformtheiranalyses,theresearch-ersranaseriesofsimulationsusingvariousassumptions,eachwithitsdefineduncertainty.Basedonthebestavailableinformationandtheirbestjudgment,theyselectedthefollowingparameterstomodel.
Scale and cost of gas resources. Basedondatafromvarioussources,anMITteamassessedexistingandpotentialnaturalgasfieldsintheworldtodeterminehowmuchgasisrecover-ableatwhatprices.Combiningthatinformation,theycreatedgassupplycurvesforallregionsoftheirmodelandthendefinedthreecases:low,mean,andhighresources.
Timing, stringency, and design of GHG mitigation policy.Theanalysislooksatthreeoptions.Thefirstassumesnoclimate-relatedpolicy.Thesecondassumesaprice-basedpolicythatimposesaneconomy-widepriceoncarbonemissionsdesignedtogradually
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reducethoseemissionsto50%below2005levelsby2050.(Thescenarioallowsno“offsets,”thatis,allactionsaretakendomestically,andemissionspermitscannotbeboughtfromabroad.)Thethirdpolicyisaregulatoryapproachthatmandatesthegradualretirementofcoalpowerplantssuchthat55%ofcurrentcoalgenerationisretiredby2050;italsorequires25%ofallelectricitytocomefromrenewablesourcesfrom2030onwards.
The technology mix. Ingeneral,theanalysesestimatethatcompetingtechnologies—specifically,nuclearpower,renewables,andcoalandnaturalgaswithcarboncaptureandstorage—continuetoberelativelyexpensivecomparedwithnaturalgas-basedtechnologies.Theyalsoestimatethatnaturalgas-poweredvehiclesdonotsignificantlypenetratethetransportationsector.
The evolution of global natural gas markets. Heretheyselecttwopossiblefutures.Oneassumesthatworldtradeinnaturalgascontinuesasitistoday:concentratedinthreeregionalmarkets—NorthAmerica,Europe,andAsia—thathavedifferingpricesandtypesofcontractsbetweenbuyersandsellers.Theotherassumesthatthereisatightlyintegratedglobalgasmarketsimilartotoday’sinternationalmarketforcrudeoil(butwithoutsuppliercartels).Theresearchersemphasizethatthosetwoviewsrepresentpolarcases.Inreality,futureglobalmarketswillfallsomewherebetweenthoseextremes.
The changing role of natural gas
Ingeneral,thesimulationsshowthatnaturalgaswillplayamajorroleintheUSenergyfuture.Withnonewclimatepolicy(andassumingthemeanresourceestimatesandregional
Imports Production–Exports Exports
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40
35
30
25
20
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Nat
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2020 2030 2040 2050 L M H L M H L M H L M H
Year
6.69.6
6.59.5
6.49.4
7.913.7
7.513.3
7.413.2
10.018.5
8.617.3
8.216.9
11.623.6
8.821.9
8.321.8
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35
30
25
20
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2020 2030 2040 2050 L M H L M H L M H L M H
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5.18.1
5.18.1
5.18.1
5.811.5
5.711.4
5.611.3
6.614.5
6.414.3
6.214.2
7.317.2
7.017.0
6.816.9
US natural gas outlook including effects of international market evolution
Regional markets
Global market
thetopsetofbarsassumesthattheregionalmarketsoftodaypersist,withtradinglargelyoccurringwithinthreemarkets:northamerica,europe,andasia.thebottomsetofbarsassumestheexistenceofatightlyintegratedglobalgasmarket(withoutsuppliercartels).withaglobalmarket,naturalgasuseishigherandpricesarelowerthanwithregionalmarkets,butbymid-centurytheusdependsonimportsforabouthalfitsnaturalgas(underthemeanresourceestimate).
L,M,H=low,mean,highresourceestimates
Price-basedpolicyineffect(seetextfordetails)
Numbersabovebars=dollarsperthousandcubicfeet(Mcf)excludingcarboncharge(top)andincludingcarboncharge(bottom)
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markets),USgasuserisessteadilyfromabout25trillioncubicfeet(Tcf)in2020toabout35Tcfin2050.Withthelowresourceestimates,gasusestillrisesslightlyandthenin2050dropsbackdowntoroughlywhereitstartedin2020.Pricesgraduallyriseovertimeaslower-costresourcesaredepleted.
Thetopchartonpage13showswhathappensifthepreviouslydescribedcarbonprice-basedpolicyisimposed(assumingregionalinternationalmarkets).Thebarsshowtotalconsump-tion,withexportsandimportsindi-cated.Aboveeachbararetwoprices.Thetoponeexcludesthecarboncharge;thebottomoneincludesit.
Withtheclimatepolicy,gasuseissomewhatlowerthanintheno-policycase,becausetotalenergyuseisreducedbythepolicy.Butitstillrisesuntilabout2040,althoughataslightlylowerrate.However,by2050gasusehasdeclined—aresponsetohighgaspricesduelargelytotheaddedcostofcarbonemissions.By2050morethanhalfthetotalpriceisduetothecarboncharge.Importsandexportsaresteadyoverthetimeperiod,anddomesticproductionexpandsuntil2050,whenitdropsback.
Impact of global gas markets
Thebottomchartonpage13showstheeffectsofchangingoneassumption:regionalmarketsarereplacedbyatightlyintegratedglobalgasmarket.Internationalgasresources(mostlyintheMiddleEastandsomeinRussia)arelikelytobelesscostlythanmostofthoseintheUS.AsthelessexpensiveUSresourcesareexhaustedandthecostofUSgasproductionrampsup,importsbecomemoreandmoreattractive.Nevertheless,domesticproductioncontinuesfromthose
Energy mix in electric generation under two emissions-control policies
Price-based policy
Regulatory approach
thetopgraphassumesaprice-basedclimatepolicythatimposesapriceoncarbonemissions;thebottomgraphassumesaregulatoryapproachthatmandatesincreasesinrenewablegenerationanddecreasesincoal-basedgeneration.(thesepoliciesareintendedforillustrationonly.fordetails,seethetechnicalreportcitedattheendofthearticle.)themoststrikingdifferenceisintotalelectricgeneration.theassumedprice-basedpolicybringsadramaticdropinelectricityuse—fargreaterthanthatelicitedbytheassumedregulatoryapproach.
Reduced Use
Gas CCS
Coal CCS
Renewables
Hydro
Nuclear
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Coal
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Year2010 2015 2020 2025 2030 2035 2040 2045 2050
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3
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1
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3.3a Electric Sector (TkWh)
GasCoal
Reduced Use
Renewables
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Coal
Year2010 2015 2020 2025 2030 2035 2040 2045 2050
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Elec
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USresourcesthatarecheaperthanimports.Inthisscenario,theUSimportsabouthalfitsgasby2050.
Somepeoplearesurprisedandsomepleasedbythoseresults.“Afterall,USproducersarestillproducing,consumerswillseecheapergasprices,andwehavealternativesourcesofgas,”saysPaltsev.“Buttheironyisthateventhoughwenowhavethiswonder-fuldomesticresource,ifaglobalnaturalgasmarketisestablished—andifit’sdrivenpurelybyeconomics,whichisabigif—thenwe’restillgoingtoendupdependingontheMiddleEastandRussia,notforoilbutfornaturalgas.Thereason:in20to30years,ourrelativelycheapdomesticgaswillhavebeenproduced,andlower-costresourcesfromothercountriescanenterthemarket.”
Energy mix in electric generation with climate policies
Howwelldoesgasdoagainstotherenergysources?Thefigurestotheleftshowforecastsofhowtheenergymixintheelectricgenerationsectorwillevolveovertime.Thetopfigureassumestheprice-basedpolicy;thebottomfigure,theregulatoryapproach.Bothanalysesassumemeanestimatesofgasresourcesandregionaltradingmarkets.
Withtheprice-basedpolicy,overallelectricityuseflattensout,andthehighpriceoffossilfuels—duetothecostofcarbonemissions—drivesdowntheiruse.Coalandoildisappearby2035,butnaturalgaskeepsdoingwelluntil2045,whenthecarbonpriceissohighthatevengasiscostly.
Thatdrop-offinnaturalgasin2045shouldgetourattention.Inalonger-termanalysisoutto2100,theresearch-
ersfoundthatnaturalgasalmostdisappearsby2075.“Soifwe’rereallyseriousaboutclimatepolicyandtoughreductionsinGHGemissions,weneedtobeworkingoneconomicallycompetitiverenewables,advancednuclearpower,andcarboncaptureandstorageforbothgasandcoal.Gasisgreat,butitisnotgoingtosolvealltheproblems,”saysPaltsev.
Thefigureassumingtheregulatoryapproachlooksquitedifferent.Here,therapidexpansionofrenew-ables—requiredbytheregulation—tendstosqueezeoutgas-basedgeneration,thoughgasremainsrelativelystrong;andcoalandoilarestillinthepicturein2050.Mostimportant,overallelectricityusedoesnotdropasitdoesundertheprice-basedpolicy—areflectionoflowerpricesduetotheabsenceofthecarboncharge.
Energy mix in all sectors
Theresearchersalsolookedattheenergymixinallsectorsoftheeconomy.Withtheeconomy-widecarbonprice,gasuseisrelativelylowinnon-electricitysectors,whereitcompetesagainstpetroleumandelectricity.Inthosecases,gasdoesnotprovideasbigacarbonadvantageasitdoesagainstcoalintheelectricsector.Withtheregulatoryapproach,gascontinuestobeamajorplayer,butcoalandespeciallyoilarestillusedin2050.
Butthemostremarkabledifferenceisintotalenergyuse.Withtheprice-basedpolicy,totalenergyusein2050isabout55quadrillionBtu;withtheregulatoryapproach,itisabout125qBtu.Whilethecarbonpriceaffectsemissionsinallsectors,theregulatoryapproachfocusesontheelectricsector,leavingotherGHG-emittingsectors
suchastransportationandindustryrelativelyunaffected.
“Theregulatoryapproachissometimesportrayedasaclimatepolicy,butitdoesn’treallybuyyoumuchintermsofemissionsreduction,”saysPaltsev.“Ifyourpoliciestargetjusttheelectric-itysector,you’renotgoingtosolvetheclimateproblem.”
Theresearchersemphasizetheroleofuncertaintyintheirstudy.Otherassumptions—greaterpenetrationofnaturalgasintothetransportationsector,forexample,orthediscoveryofvastamountsofshalegasinChina—wouldprofoundlyaltertheirresults.Nevertheless,theybelievethattheirscenarioshelptoprovideboundsonfutureprospectsfornaturalgasandillustratetherelativeimpor-tanceofdifferentfactorsindrivingtheresults.
• • •
By Nancy W. Stauffer, MITEI
This analysis was carried out as part of an interdisciplinary study, The Future of Natural Gas (see page 31). Development of the economic models applied in this work was supported by the US Department of Energy, Office of Biological and Environmental Research; the US Environmental Protection Agency; the Electric Power Research Institute; and a consortium of industry and foundation sponsors through the MIT Joint Program on the Science and Policy of Global Change. More information can be found in:
S. Paltsev, H. Jacoby, J. Reilly, Q. Ejaz, F. O’Sullivan, J. Morris, S. Rausch, N. Winchester, and O. Kragha. The Future of US Natural Gas Production, Use, and Trade. MIT Joint Program on the Science and Policy of Global Change, Report No. 186, June 2010. Available at globalchange.mit.edu/pubs/reports.php.
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Underground storage of carbon dioxideMicrobes may help seal it in
Storingcapturedcarbondioxide(CO2)emissionsundergroundisonewaytokeepthatgreenhousegasfromenteringtheatmosphere.ButhowcanweensurethattheCO2willnotleakoutovertime?MITresearchershaveidentifiedanunlikelysourceofhelp:amicrobethatthrivesintheharshenvironmentofaCO2-filledreservoirandnaturallysecretesafilmthatcould—likeplasticwrap—sealthereservoirshut.Asanaddedbonus,themicrobemaycatalyzereactionsthathelptheCO2becomepartofthesurroundingrock—theultimateinleakprevention.
“Tomyknowledge,ourgroupisthefirsttoreportmeasurementsofmicro-bialgrowthunderconditionsofCO2sequestration,”saysJanelleR.Thomp-son,directoroftheprojectandtheDohertyAssistantProfessorinOceanUtilizationintheDepartmentofCivilandEnvironmentalEngineering.Thompsonnotesthatthosefindingsmayhaveimplicationsforthelong-termstabilityandintegrityofCO2-filledreservoirsandthereforefortheviabilityofcarboncaptureandsequestration(CCS)asaclimatechangemediator.
IntheCCSprocess,CO2iscapturedfrommajoremissionssourcessuchaspowerplantsandthencompressed,transported,andinjectedintodeepgeologicformations,salineaquifers,orotherreservoirsforlong-termstorage.“Butatthedensitiesanddepthsinvolved,CO2isquitebuoyant,somakingsureitdoesn’tleakbackoutintotheatmosphereisamajorconcern,”saysThompson.
Ingeneral,asequestrationreservoirconsistsofporousrocksuchassand-stoneoverlaidbyalesspermeablelayersuchasshale.Butoftentherearewellboresdrilleddownthroughthe“cap”rock—signsofearlierexploration
foroil.Thoseopeningshavebeensealedwithcement,butCO2pluswaterformsanacidthatcancorrodethecement.Asaresult,sequesteredCO2couldescapenotonlythroughsmallnaturalfracturesbutalsothroughintentionallydrilledwellboresfilledwithcrumblingcement.
Oneapproachtosecuringsuchreser-voirsinvolvesbiofilmbarriers.SaysThompson,“Ifwecanstimulatemicroorganismstogrowunderneaththecaprock,theymaycreateasheetofslimeandgoothatwilleffectivelysealshutthecementplugsandotherpossibleescaperoutes.”Thediagramtotherightillustratestheconcept.
Othergroupshavedemonstratedthatbiofilmscreatedbymicrobescanretardthemovementof“supercritical”CO2—ahighlyconcentrated,high-pressuregas—throughporousrock.ButcanmicrobesliveandgrowinthepresenceofsupercriticalCO2?Mostexpertsassumethatconditionswouldbetooharshforthemtoexist.
Totestthatassumption,Thompsonandhercivilandenvironmentalengineeringcolleagues—HectorH.Hernandez,postdoctoralassociate,andKyleC.Peet,graduatestudentand2008–2009BP-MITEnergyFellow—gothelpfrominvestigatorswhowererunningpilot-scaletestsofcarbonsequestrationinFrioRidge,Texas.Inthosetests,teamsfromtheUniversityofTennesseeandOakRidgeNationalLaboratoryinjectedsupercriticalCO2intoa1.5km-deepsalineformationfor10days,collectinggroundwatersamplesastheundergroundplumeevolved.Theythenfilteredthesamplestotrapthebiomass,someofwhichtheysenttoThompson’steam.
Usingaspeciallydesignedhigh-pressuregrowthchamber,theMITresearcherscultivatedthebiomasssamplesinthepresenceofnutrientsatconditionsmimickingthoseinaCO2sequestrationreservoir.Andmicrobesinthesamplesgrew.Theydoubledaboutonceeverydayandahalf.Examinationofstainedsamplesfromthebioreactorunderafluorescentmicroscoperevealedclustersofcells,each0.5–1.0micronindiameter,surroundedbyathicklayerofextracellularmaterial.
Closer examination
Ideally,Thompsonandherteamwantedtoworkwithasingle,purestrainsothattheycouldstudyitsphysiologyandgeneticmakeupindetail.“Thebetterweunderstandmicrobialgrowthandactivityinhigh-pressureCO2environ-ments,thebetterwecanengineerbiofilmbarriersinsequestrationreservoirs,”saysThompson.Andbydeterminingthegeneticmechanismsthatenableastraintotoleratesuper-criticalCO2theymightbeabletoidentifyorgeneticallyengineerstrainswithevenhighertolerance.
Tosingleoutthebeststrain,theyusedaprocesscalleddilutionsubculturing.Theyallowedtheirmixtureoforgan-ismstogrowforaperiodoftimeandthenremovedsamplesthattheyusedasan“inoculant”forthenextgrowth.Byreplicatingthatprocess,theyweededouttheweakerstrainsandendedupwiththefittestones.(Ateachstep,theycryo-preservedsomesamplessothattheycanregrowtheentiremixtureifnecessary.)
Ultimately,theyidentifiedasinglestrainthatdoesnotjusttoleratehigh-pressureCO2butactuallyrequiresahigh-pressureenvironmentforsurvival—acharac-teristicthatclassifiesitasan“obligate
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2
Microbes
Carbon dioxide
Sediment grain
Sediment grain
Biofilm
Water
Biofilm
Conceptual model of microbial growth in a sequestration reservoir
barophile.”Insubsequenttesting,theyfoundthatthisstraincannotsurviveat1atmosphereofpressurebutgrowsnicelyat120atmospheres—innitrogenaswellasCO2.
Todeterminetheidentityofthestrainwiththisunusualcharacteristic,theresearcherssequencedasectionofthemicrobe’sDNA—specifically,asectionfromthe16SribosomalRNAgene.Thatgeneisausefultool:someregionsofitarecriticaltocellularmetabolismsotheyarethesameinallorganismswhileotherregionscanvary,exhibitingclock-likeevolutionarybehavior.“Sowecantakethe16Sgenefromseveralorganisms,lineuptheconstantregions,andthencomparethevariableregionstoseehowtheorganismshavedivergedovertime,”explainsThompson.
Theiranalysisshowedthatatthe16SgenetheirstrainiscloselyrelatedtoBacillus cereus,awell-knownorganismthatincludesstrainsthat
causefood-borneillnessinhumansandotherstrainsthatareusedasprobioticsinanimals.“Tomysurprise,oursubsurfacestrain—anobligatebarophile—hasalmostthesame16SribosomalRNAgenesequenceasaknownnon-barophilicstrainthatlivesonthesurfaceandcanbeeitherpathogenicornon-pathogenic,”saysThompson.
Thenextstepistosequencetheentiregenomeoftheirmicrobeandcompareittothealready-sequencedgenomeoftheBacillus cereus.SeeingwherethegenomicsignaturesofthetwostrainsdifferwillprovideimportantcluesintothemolecularadaptationsthatenabletheirmicrobetosurviveinthepresenceofsupercriticalCO2whilecloselyrelatedstrainscannot.
Other ongoing work
Thompsonandherteamarecontinuingtoexaminethephysiologyoftheirstrainandareworkingtodetermineconditionsthatwilloptimizeitsabilitytogrowandtomakeextracellularbiofilms.Theyarealsousingfluores-centmicroscopytoexaminethethree-dimensionalarchitectureofthebiofilmandthespatialorientationofthemicrobialcellswithinit.
Inotherwork,theyareexaminingtheeffectsoftheirmicrobeon“mineraltrapping,”anotherprocessthatwillpreventCO2leakage.Here,theCO2chemicallyreactswithrockmineralstoformsolidcarbonatecompounds.Therateatwhichthatreactionoccursdependsontemperatureandvariousaspectsofthereservoir’schemicalenvironment—allofwhichhasbeencapturedincomputermodelsofreservoirbehavior.
Inthosemodels,oneofthekeyfactorslimitingthereactionrate—andhencemineraltrapping—istheavailabilityinthesubsurfaceofpositivelychargedparticlescalledcations.Researchhasshownthatmicroorganismscandissolvesilicateminerals,aprocessthatreleasescationsandcouldpoten-tiallyacceleratethosereactionratesbymanyordersofmagnitude.However,currentmodelsgenerallyassumeasterileenvironment,sotheimpactofmicrobialactivityonmineraltrappingisdiscounted.
“Wenowknowthatmicrobeswillbepresent,soweplantolookathowmuchtheymayacceleratetheproduc-tionofcations,”saysThompson.“Ifwecanmeasureandquantifythatrate,thenthatinformationcanbefedintothemodelsofreservoirbehaviornow
thisschematicillustrateshowabiofilmbarriercanpreventtheescapeofcarbondioxide(co2)throughporesinasequestrationreservoir.theenlargedimageattheleftshowsclustersofmicrobes(blue)suspendedintheirextracellularbiofilm(green)betweentwograinsofsediment(gray).theimageattherightshowsthestoredco2andwateraheadofitbeingstoppedbythebiofilm,whichshutsoffspacesamongthegrainsandkeepstheco2frommigrating.
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New insights into capturing solar energy
beingdeveloped.Theimpactontheoutcomemayormaynotbesignifi-cant—buteitherwayweneedtoknow.”
Thompsonstressestheneedtocon-sidermicrobialactivitiesinstudiesofCCS.Whilelotsofpeopleareworkinginthefieldofgeologiccarbonsequestra-tion,relativelyfewarethinkingaboutmicrobes.“Butmicrobialactivityissomethingthatyoujustcan’tignore.It’spresentineveryenvironment,andit’sessentialtolifeasweknowitonplanetEarth,”shesays.“Ithinkit’sreasonabletoassumethatitwillplayaroleintrappingandtransformingthesequesteredCO2,andweneedtotakethatroleintoaccountasweexploretheviabilityofcarbonsequestration.”
• • •
By Nancy W. Stauffer, MITEI
This research was funded by a seed grant from the MIT Energy Initiative and by the US Department of Energy’s National Energy Technologies Laboratory. Publications are forthcoming.
AnMITteamhasdevelopedasimula-tiontechniquethatcanprovidecriticalinsightsintothebehaviorofelectronswithinsunlight-drivendevicesusingdays,notdecades,ofcomputertime.Usingtheirtechnique,theyhavecalculatedhowelectronsmovewithinanamorphousphotovoltaic(PV)system.Theabilitytounderstandsuchprocessesattheatomiclevelwillhelptoacceleratetheimprovementoftechnologiesforturningsolarenergyintousefulformssuchaselectricity.
Mostpeopleagreethatsunlightispotentiallyourbestlong-termsourceofabundantenergy.“Butwecan’trunourcarsonit,”saysTroyVanVoorhis,associateprofessorofchemistry.“Weneedtoconvertitintosomeotherform—electricityorhydrogenorliquidfuels.”Heandhisteamfocusontwoapproaches:PVtechnologytoconvertsunlightintoelectricityandphotochemistrytoproducechemicalfuels.Inbothcases,cutting-edgetechnologiesrelyoncarefullyselectedmoleculestoachievetheconversion.
Whilethosetechnologiesdothejob,theyaremuchlessefficientthantheorysuggeststheycouldbe,andscientistsdon’talwaysunderstandwhy.“Wehaveageneralideaofthefundamentalprocessesinvolved,butthedetailedphysicsofwhyonedeviceworksbetterthananotherorwhythismoleculeworksandthatonedoesn’t—thosethingsaremuchmoreopaque,”saysVanVoorhis.
The PV challenge
Asanexample,hedescribeswhathappensinaPVdevice.Typically,thedeviceismadeoftwomaterialswithdifferingelectronenergylevels.Whenaphoton(apacketofsunlight)strikesamoleculeinoneofthematerials,themoleculegainsextraenergy.Thatextraenergycanmigratethroughthedevicetotheinterfaceofthetwomaterials.There,theenergizedmaterialcandissipatetheextraenergybylosinganelectrontoaneighboringmoleculeintheothermaterial—aprocessthatleavesbehindavacancycalledahole.Overtime,holesaccumu-lateinthefirstmaterialandelectronsinthesecond.Iftheoutsideedgesofthetwomaterialsareconnectedbyacircuit,theelectronswillflowbacktothefirstmaterialasacurrent.
Thedescriptionofthatprocessleadstoseveralsimpledesignprinciples.Forexample,thebestresultscomewhenonematerialhasastrong“affinity”forelectronsandtheotherforholes.Andagooddesignhaslotsofinterfacebetweenthetwomaterialssothattheabsorbedenergydoesn’thavefartogotoreachtheinterface—abenefitbecauseenergydoesnotflowquicklythroughbulkmaterial.
Microscopicstudiesconfirmthoseprinciples:PVdevicesthatperformwelltendtohaveasandwichstructurewithalternatinglayersofthetwomaterials.Butfiguringouthowtoencourageanelectrontojumpacrosstheinterface,howtomaximizeitssubsequentmobility,andhowtokeepelectronsandholesfromrecombiningrequiresafarmorefundamentallevelofunderstandingofwhatisgoingon—ajobforcomputersimulation.
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2.5
2.0
1.5Density of states
In donor material
In acceptormaterial
During chargetransfer at interfaceE
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Modeling organic photovoltaics
MMmodelofinterface
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ResultsfromanalysisusingMM/QMmodel
exampleofmittechniqueforsimulatingcriticalprocessessuchasthosethatoccurwithinaphotovoltaicdevicemadeofamorphousorganicsemiconductors.theleft-handdrawingshowsamolecularmechanical(mm)modelofasampleinterfacebetweentwomaterialsinsuchadevice.themiddledrawingshowsaquantummechanical(Qm)modelofanimportantsubsystemwithinthatmmmodel.theright-handdrawingpresentsresultsfromananalysisinwhichanmm/Qmmodelwasrun1,000timeswithvaryingparameters.
Simulating the system
Oneapproachismolecularmechanical(MM)modeling,whichdrawsonclassicalmechanicsandNewton’slawsandfocusesontheforcesconnectingatomstogethertomakemolecules.Theelectronsthatactuallyholdtheatomstogetherarenotspecified,buttheireffectisrepresentedbybondsbetweenatoms.Thebondscanbethoughtofasrubberbandsaroundtwoatomsorthreeatomstokeepthemfrompullingawayfromoneanother.
MMmodelsarevaluableandefficientcomputationaltoolsformanyapplica-tions.ButtheydonotprovidethedetailsneededbyscientiststryingtoimprovePVdevices.Forexample,theydonottellhowstifftherubberbandsare—thatis,howstrongthebondsare—ordefinetheelectronorholeaffinityofmoleculesorhowelectronsmoveabout.
Capturingthosedetailsrequiresquantummechanical(QM)modeling,anapproachdrawingontheories
thatexplainthebehaviorofmatterandenergyattheatomicandsubatomicscale.Butinadevicejust100nano-meterswide,therearemillionsofelectrons,andalloftheminteract.Sotrackingthemigrationofasingleelectronthroughthedevice(ifitwerepossible)wouldrequiresimulatingthebehaviorofallthoseelectrons.RunningthenecessaryQMcalculationswouldtakedecades—evenwithtoday’sfastestcomputers.
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An integrated approach
Thesolutiontothedilemmacomesinrealizingthatitisnotnecessarytounderstandtheentiresystematthequantumlevel.Indeed,theregionsthatneedtobeanalyzedwithQMmethodsmayincludejustafewmolecules—whatVanVoorhiscalls“thesubsystemsofinterest.”
Toperformasimulation,therefore,theresearchersbeginbyperformingMMmodelingoftheoverallsystemtodefinetheimportantsubsystemsandhowlikelyeachoneistooccur.TheythenuseQMmodelingoneachtypeofsubsystemtocalculatethecriticalparametersthatMMmodelingcannotaddress.“Becausethesubsystemsarerelativelysmall,”saysVanVoorhis,“thosesimula-tionstakeafewhoursratherthandecades.”
Thenextstepisto“train”theMMmodelusingtheQMresults.TheresearchersdefineparametersfortheMMmodel—forinstance,thestrengthofbonds—basedonwhattheirQMmodelrevealedaboutthelocalinteractionsamongelectrons,atoms,andmolecules.“Weassumethatthebiggersystemhasthesamelocalinteractions,simplyrepeatedonalargerscale,”saysVanVoorhis.
Finally,theyruntheirrefinedMMmodeloftheoverallsystemtocalculatetheimpactofincomingphotonsattheinterfaceandtoseehowthesubsystemsofinterestaffectandareaffectedbythebroaderenvironmentincludedintheMMmodel.
New ability to probe PVs
Inrecentwork,theresearchersusedtheirtechniquetoexaminePVsmadeofamorphousorganicsemiconductors.Thesematerialsaremoreflexibleandeasiertoprocessthantheirsingle-crystalcounterparts,buttheycanbehardertounderstand.Insingle-crystalPVs,thelocationsofthemoleculesareknown;inamorphousmaterials,themoleculesarenotorderedbutmixedup,andtheirlocationschangeovertime.VanVoorhislikensittotrafficoncitystreets.“Itmaylookorderedinasinglesnapshot,butsequentialsnap-shotsmayshowtrafficmovingandchanginglanesandsoon—that’sdisorder,”hesays.“Likewise,inadevice,moleculesmaybevibratingandmovingandfluctuating,andIneedtoknowhowthat’sgoingtoaffecttheoperationofmydevice.SoIneedtolookatsubsystemsatdifferentplacesandatdifferenttimes.”ThatabilitycouldprovidecluestopreventingthebiggestproblemwiththesepromisingPVs:thetendencyofelectronsandholestorecombine.
Thefigureonpage19demonstratesthetechnique.Theleft-handdrawingshowsasampleinterface(atthenanometer-lengthscale)simulatedbytheMMmodel.Withinitisasubsystemofinterest,expandedinthemiddledrawing.Butthatsnapshotshowsjustonesubsystematonetime.Tocapturetheeffectsofdisorder,themodelmustexaminemanysubsystemsatmanytimes.“Soinordertogetarealisticpicture,Iactuallyhavetoanalyzeathousandsnapshots,”saysVanVoorhis.Ahundredcomputersworkinginparallelcanperformallthoseanalyseswithinafewhours.
Theright-handdrawingshowsresultsfromsuchastudy.Thethreecurvesshowtheenergylevelsofelectronsinthedonormaterial(red),intheacceptormaterial(blue),andtransferringbetweenthem(green).Ineachcase,thewidthofthedistributionreflectsthepresenceofmanydifferentsubsys-temswithslightlydifferentproperties.Theresultsareconsistentwithwhatothershaveobservedinexperimentswiththesematerials.
VanVoorhisandhisteamarecontinu-ingtousetheirnewmodelingtechniquetolookatdifferentPVdevicesaswellasphotochemicalprocessesforproducinghydrogenandliquidfuels.“ThenatureofthesesystemsmakesitnecessarytotailorthedetailedforcesintheMMmodeltoaparticulardeviceorprocess,”saysVanVoorhis.“Butasourresultshaveshown,theoutcomecanbeanewunderstandingofhowsolar-drivendevicesandprocessesworkandthereforenewstrategiesforimprovingtheirefficiencyandperformance.”
• • •
By Nancy W. Stauffer, MITEI
This research was supported by an ignition grant from the MIT Energy Initiative, a fellowship from the David & Lucille Packard Foundation, and the US Department of Energy. Further information can be found in:
S. Difley, L.-P. Wang, S. Yeganeh, S. Yost, and T. Van Voorhis. “Electronic properties of disordered organic semiconductors via QM/MM simulations.” Accounts of Chemical Research, v. 43, no. 7, July 2010, pp. 995-1004. DOI: 10.1021/ar900246s.
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MITEI awards fifth round of seed grants for energy research
informationonthevulnerabilityofelectricalgridcomponentscanhelputilitycompaniesplanrepairworksoastoreduceservicefailuresandincreasepublicsafety.thisimageshowsamanholeinthechelseaneighborhoodofmanhattanthatwashighlyrankedbythevulnerabilitymodelofprofessorcynthiarudinandhercolleagues,publishedinthejournalMachine LearninginJuly2010.dotssuperimposedonthesatelliteimagearemanholes,coloredaccordingtothepredictedvulnerabilityofthemanholetoseriousevents(firesandexplosions).redindicateshighervulnerability;whiteindicateslowervulnerability.linesconnectingthemanholesrepresentundergroundelectricalcables.
TheMITEnergyInitiative’slatestroundofseedgrantsforenergyresearchissupportinginnovativeworkonsolarenergyconversion,fuelcellcatalysts,algorithmsforenergy-efficientcomputing,systemsforintegratingrenewabletechnologiesintosmartgrids,andmore.Inthisround,atotalof$1.9millionwasawardedto13projects,eachlastingbetweenoneandtwoyears.Thefundedprojectsspan10departments,laborato-ries,centers,andinstitutes.
Asinpreviousrounds,manyofthenewawardsinvolvejuniorfacultyandfacultynotpreviouslyengagedinenergy-relatedresearch.Forexample,CynthiaRudin,assistantprofessorofstatisticsattheMITSloanSchoolofManagement,isseekingtoincreasethereliabilityoftheelectricpowergrid—agrowingchallengeduetoaginginfrastructurecombinedwiththeevolutionofnewwaysofusingthegrid.Rudinandothershavedevelopedstatisticalmethodsthatpredictthevulnerabilityofcomponents—informationthathelpsutilitycompaniesdesignmaintenanceplansthatreduceservicefailuresandincreasepublicsafety(seethefigure).Butsuchpredic-tionsmustalsobe“actionable,”thatis,theremustbenointermediatestepsbetweenthedesignofthevulnerabilitymodelandtheprioritizationofrepairwork.Rudin’steamwilldevelopaframeworkfor“actionableranking”thatwillimmediatelyyieldmethodsforimprovingthereliabilityandsafetyofelectricaldistributionnetworks.
Inanotherproject,EvelynWang,assistantprofessorofmechanicalengineering,isfocusingonthermalmanagementforconcentratedsolarenergyconversionsystems.Suchsystemscoulddeliverasmuch
as25%oftheworld’sprojectedpowerneedsby2050.However,increasingtheirpowerproductionrequiresconcentratingsunlightontosmallerandsmallerareasofthesolarabsorber,whichleadstosignificantheatgenera-tionandreductionsinelectricityoutput.Wangandherteamaredevelopinganinnovative,completelypassivenanofilm-basedcoolingsystemthatcanachievehighratesofheatremovalwithlowthermalresistance.Thecoolingachievedwillpermitevenhigherconcentrationstobeused,enablingmajoradvancesinsolarconversiontechnologiesandotherimportantenergysystems.
Carboncaptureandsequestration(CCS)isthefocusofaprojectledbyAlisonMalcolm,assistantprofessor,andMichaelFehler,seniorresearchscientist,bothofearth,atmospheric,andplanetarysciencesandMIT’sEarth
ResourcesLaboratory.TheindustrialviabilityofCCSrequiresreliabletechniquesfordeterminingtheamountandlocationofthesequesteredcarbondioxide(CO2)andfordetectingpotentialleakage.Theoilindustryhasseismic-basedmethodsthatcanalmostcertainlybeadaptedtoperformthosetasks,buttheirhighcostwilllikelyprecludetheiruseateverysequestrationsite.Theresearchersarethereforedevelopingnewimagingmethodsthatshouldbeable—withasignificantlysmallerdataset—todelineatethespatialdistributionofinjectedCO2inareservoirandothermethodsthatcanactasalarms,detectingCO2leakagethroughthecaprock.Themethodsaredesignedtoworktogether,guaranteeingthestablesequestrationoftheCO2inthesubsurface.
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JohnJoannopoulos,FrancisWrightDavisProfessorofPhysicsanddirectoroftheInstituteforSoldierNanotech-nologies(ISN),andSrinivasDevadas,professorofelectricalengineeringandcomputerscience—bothnewcom-erstoMITEI—plusIvanCelanovic,researchengineerintheISN,areaddressingpowerelectronicsandtheirroleinincorporatingrenewableenergygenerationsourcesintothefuturesmartgrid.TheMITteamwilldevelopanddeploynoveldigitaltoolsforthedesignandtestingofpowerelectronics-enabledrenewablesintegratedintothesmartgrid.Enablingreal-timesimulationswithultra-highfidelitywillrevolutionizethedesignofpowerelectronicssinceitwillallowreal-timemeasurementandcontrolofprototypesystemsthatcanberedesigned,refined,ortunedforincreasedreliabilityandefficiency.Theconceptwillbedemonstratedontworepresentativesystems—thevariablespeedwindturbineandthehybrid-electricvehicle.
MartinBazant,associateprofessorofchemicalengineering,isfocusingonadifferentenergy-relatedconcern:thegrowingglobalshortageoffreshwater.Massiveamountsofenergyarerequiredtotransportorproducefreshwaterfromseawater,especiallyforremotelocations.Acriticalgoalforenergy-relatedresearchandpolicyisthereforedevelopingnewmeansofwaterdesalinationandpurification.Inthisseedproject,Bazantandhiscolleagueswillfocuson“shockelectrodialysis,”anovelelectrochemicalapproachtoachievingthoseprocesses.Theapproachexploitsthespontaneousseparationofsaltandchargedimpuri-tiesfrompurewaterinchargedporousmedia,passingcurrenttoelectro-dialysismembranes.Theresearchers
willexplorethebasicphysicsofdesalinationshocksinmicrostructuresandwillbegintoengineeranewclassofdesalinationsystemsthatarebothenergyefficientandwellsuitedforsmall-scale,portableapplicationssuchasinremoteregionsorforthemilitary.
Asinthepast,theresponsetoMITEI’scallforproposalswasstrong,with44submissionsinvolvingatotalofalmost70researchers,accordingtoErnestJ.Moniz,directorofMITEIandtheCecilandIdaGreenProfessorofPhysicsandEngineeringSystems.“Onceagain,theproposalsincludedsurprising,thoughtful,andpotentiallyimpactfulconceptsandideas,”hesaid.“Thetaskofchoosingamongthemwaschallengingforthereviewcommittee,whichconsistsoffacultyontheMITEnergyCouncilandrepre-sentativesfromMITEI’sFoundingandSustainingmembers.”
FundingforthenewgrantscomeschieflyfromMITEI’sFoundingandSustainingmemberssupplementedbyfundsfromtheChesonisFamilyFoundation,ananonymousdonor,andMITEI.
Todate,MITEI’sseedgrantprogramhassupported67early-stageresearchproposals,withtotalfundingofmorethan$8.4million.Inaddition,eightgroupshavebeenawardedsmaller,shorter-termignitionandplanninggrants.
“Asprojectsfromthefirstfewroundsofawardsarecompleted,we’rereceivingreports,papers,andpresenta-tionsthathaveresultedfromthem,”saidRobertArmstrong,deputydirectorofMITEIandtheChevronProfessorofChemicalEngineering.“Someof
thosenovelprojectshavealreadyhadsignificantpracticalimpacts,whileothershaveledtolong-termfunding,openingupnewandexcitingareasofresearchfortheInstitute.”
• • •
By Nancy W. Stauffer, MITEI
For a complete list of awards, please see page 40.
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A breath of fresh airStudents explore alternatives for lab safety test
uropadvisorpamelagreenley(left),associatedirectoroftheenvironment,health,andsafetyoffice,observeswunminwong’11(center)andevelynZuniga’13(right)astheysetupequipmentforexperimentswithatracergasthatwouldbemoreenvironmentallyfriendlythantheonenowusedintestsoffumehoodperformance.themannequinatthefarleft(affectionatelynamed“betty”bythestudentresearchers)simulatesalaboratoryresearcherandplaysakeyroleindetermininghowwellthefumehoodcontainsthetracergas—anindicatorofitsefficacyatprotectinghumanusersfromnoxiousfumes.
AgasknownasSF6—odorless,color-less,andnonflammable—insulatesdouble-panedwindowsandhelpsbloodvesselsshowuponultrasounds.AtMITandelsewhere,itisalsowidelyusedasatracergastodeterminewhetherlaboratoryventilationhoodsareworkingtoprotectusersfromnoxiousfumes.
Butthere’saproblem.SF6—properlycalledsulfurhexafluoride—isconsideredtobethemostpotentgreenhousegasevaluatedbytheIntergovernmentalPanelonClimateChange.Over100years,SF6hasaglobalwarmingpotentialthatis22,200timesthatofcarbondioxide.Alarmingly,theconcentrationofSF6intheatmosphereisincreasing.
Inresponsetothoseconcerns,MITstudentshavebeeninvestigatingthepossibilityofswitchingtoadifferenttracergasthatwouldhavealess-negativeenvironmentalimpact.Inspring2010,then-freshmanEvelynL.ZunigacameupontheTracerGasSubstituteTestUROPprojectafteradetailedsearchoftheMITEnergyInitiative(MITEI)website.TheprojectwasdevelopedandfundedbytheEnvironment,Health,andSafety(EHS)OfficeincollaborationwithMITEIaspartofaninnovativeprogramtobringstudentexpertisetobearonMIT’sreal-worldcampusenergyandenvironmentalchallenges.
Zuniga,amaterialsscienceandengineeringmajor,jumpedatthehands-onproject,asdidWunMinWong,thenajuniorintheMITSloanSchoolofManagement.“I’mdeeplyinterestedinsustainabilityandenergy,particularlyMIT’sinitiativestobeamore‘green’campus,”saysZuniga.“PamGreenley(associatedirectorofEHS)andLesNorford(professorofbuilding
technology)whoservedasadvisorsontheprojectwereabsolutelyamazing,andtheirexcitementfortheprojectwasalsoamotivationforme.”
Morethan1millionfumehoodsintheUnitedStatesmustbetestedtomeetnationalindustrystandards,sotheimpactofthegasusedintheprocesscanbesignificant.GreenleysaidshedevelopedtheUROPprojectbecauseastudyatSanFranciscoStateUniversityindicatedthatnitrousoxidemightbeapromisingsubstituteforSF6intestingtheoperationofthe1,000-plusfumehoodsontheMITcampus.“Wedon’twanttoseehealthandsafetyissuesnegativelyimpactedbecauseofenvi-ronmentalissues,”shesays.“If(SF6)hasgottenthatserious,it’sworthfindingadifferentgas.”
ReducingenergyusefromMIT’subiquitousfumehoodshasbeenapriorityfortheInstitute,whichhasachievedsignificantenergysavingsbyloweringthevolumeofairmovingthroughnearly200hoodsoncampusfrom100to80feetperminute.Testingtheeffectsofthischangehighlightedtheopportunitytoconsideralternativeapproaches.ProfessionallyconductedtestsusingSF6provedthelowerflowratesweresafe.ZunigaandWongrepeatedsomeofthosetestswithnitrousoxideaswellasSF6andcomparedtheresults.
Withaccesstoalabfullofunusedfumehoods,ZunigaandWongwenttoworkinBuilding18threemorningsaweek.Usingamannequinwithsamplingtubesattachedtoitsface,thestudentsmimickedthereal-timeuseoffume
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hoodsandmeasuredchangesinairflowpatternswithinthelaboratoryequipment.“Thegoalistomaketestscloserandclosertoreal-worldconditionswithoutbeingtoocostlyortoocumbersome,”Greenleysays.
“Thisprojectwasmyfirstlab-basedUROP,”saysWong.“IwasgladthatIgainedusefullabskillsdespitecomingfromamanagementsciencebackground.”
Duringfall2010,mechanicalengineer-ingseniorEricGuffeyfocusedhisseniorthesisonthiswork,continuingwhereZunigaandWongleftoffwiththenitrousoxide-SF6comparison.Hehasbeenconductingamorethoroughanalysisofthedatacollectedinthespring,andhealsohasperformedsomeofhisowntestingoffumehoodsaroundcampus,includinginthe
chemistry,mechanicalengineering,andmaterialsscienceandengineeringdepartments,attheKochInstitute,andatMITFacilities.
“ThisprojectisagreatexampleofhowwecanpartnerwithMITEItousethecampusasalearninglab,withstudents,faculty,andstaffworkingtogetheronglobalproblems,”saysNorford.MITEIworkswithmembersofthecommunityfromacrossMITtodevelopprojectsthatbenefitboththeInstituteandthestudents.
AsherfirstUROP,theprojecthelpedZunigagain“essentiallabskillsandagreatintroductiontoresearch,”shesays.“CollaboratingwithWunMin,IalsolearnedalotaboutlabproceduresandMITingeneral.ButthemostinterestingpartformewastoseealltheopportunitiesMIToffersforways
topositivelyimpacttheenvironment,andIwasexcitedthatevenasafreshmanIwasabletotakepartintheinitiativeandmakeanimpact.”
• • •
By Deborah Halber, MITEI correspondent
uropstudentevelynZunigaadjuststhereleaseofthetracergassubstituteintothefumehoodas“betty”thetestmannequinlookson.anairintakeatbetty’smouthandnosewillsimulatethebreathingofaresearchertotestforthepossiblepresenceofthetracergasinfrontofthefumehood.
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Named Energy Fellows, 2010–2011
ABB Erica Lin MaterialsScienceand
EngineeringPeter Montag Physics
b_TECMatthew Aldrich MediaArtsandSciences
Bosch Kaitlin Goldstein ArchitectureFahri Hizir MechanicalEngineering
BP Kenny Ching MITSloanSchool
ofManagementBomy Lee ChungChemicalEngineeringAdam Freedman CivilandEnvironmental
EngineeringWen MaNuclearScienceandEngineeringAndrew NanopoulosMechanical
EngineeringPeter SwartzPoliticalSciencePing WongMechanicalEngineeringGuoqiang Xu MaterialsScience
andEngineering
ChevronAditya KunjapurChemicalEngineeringJames MeredithMechanicalEngineering
CumminsTommy LeungEngineering
SystemsDivision
DenburyIbrahim Toukan EngineeringSystems
Division
EDFLindsey GilmanNuclearScience
andEngineering
EnelGiancarlo Lenci NuclearScience
andEngineeringMatthew ThomsMechanicalEngineering
EniJennifer BrophyBiologicalEngineeringMartina CocciaEarth,Atmospheric,
andPlanetarySciencesDaniel GrahamChemistrySayalee MahajanChemicalEngineeringDavid RambergEngineering
SystemsDivisionDaniel RowlandsChemistrySven Schlumpberger Chemical
EngineeringRuoshi Sun MaterialsScience
andEngineeringGregory ThielMechanicalEngineeringQing XuChemicalEngineering
ExelonJohn Michael HagertyEngineering
SystemsDivision
GTIKaren Tapia-AhumadaEngineering
SystemsDivision
Lockheed MartinSudhish BakkuEarth,Atmospheric,
andPlanetarySciencesKento MasuyamaAeronautics
andAstronautics
Saudi AramcoPo-Yen ChenChemicalEngineeringEric HontzChemistry
SchlumbergerDavid Cohen-TanugiMaterialsScience
andEngineeringMatthew D’AsaroElectricalEngineering
andComputerScience
ShellQin CaoEarth,Atmospheric,and
PlanetarySciencesDiana ChienBiologyJohn RansonElectricalEngineering
andComputerScienceDavid RosenElectricalEngineeringand
ComputerScienceJacob RubensBiologyYunjian XuAeronauticsandAstronauticsTauhid ZamanElectricalEngineering
andComputerScience
SiemensWilliam Hasenplaugh Electrical
EngineeringandComputerScienceLeah Stokes UrbanStudiesandPlanning
TotalRuel Jerry Earth,Atmospheric,
andPlanetarySciencesRebecca Saari Engineering
SystemsDivisionBenzhong ZhaoCivilandEnvironmental
Engineering
WeatherfordAlan Lai MaterialsScience
andEngineeringMichael ReppertChemistry
TheSocietyofEnergyFellowsatMITwelcomed52newmembersinSeptem-ber2010.TheEnergyFellowsnetworknowtotals139graduatestudentsandspans20MITdepartmentsanddivisionsandallfiveMITschools.Thisyear’sgraduatefellowshipsaremadepossiblethroughthegeneroussupportof19MITEImembercompanies.
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MITEI’s undergraduate energy research flourishes
above:sharonXu’13ofarchitecture(center)downloadswindspeeddatafromananemometeratopbuildinge52anddiscussesnextstepsinthecampuswindresourcemonitoringprojectwithresearchadvisorstephenconnorsofthemitenergyinitiativeandgraduateadvisorKathleenaraujoofurbanstudiesandplanning.
pretreatmentofsugarcanebagasse(shownhere)hasyieldedhighlevelsoffermentablesugars—akeystepinproducingethanolfromsuchligno-cellulosicmaterials.thatresearchhelpedguidestudentswork-ingwithotherfeed-stocks(seebelow).
rebeccaKrentz-wee‘12ofnuclearscienceandengineeringreviewsageologicmapofcaliforniatodeterminetheviabilityofheavyoilreservoirstoserveasheatstoragesystemsforcombinednuclear-geothermalpeakelectricityproduction.
perrynga’12(left)andsebastianvelez’12ofchemicalengineeringdiscusstheiruropprojectsaimedatdevelopinglessexpensive,moreefficientmethodsofproducinghighethanolyieldsusingsorghumforagebagasseandligno-cellulosicmaterialsasfeedstocks.
Jenniferhammond’12ofmechanicalengineeringdemonstratesadevicethatmeasuresthereflectivityofasurface.usingthedevice,shehasbeenexamininghowdustorsanddepositedonreflectivesurfacescanreducetheefficiencyofaparabolicsolartroughinthedesert.
e d u c a t i o n
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studentsworkedonenergy-relatedUndergraduateResearchOpportunitiesProgram(UROP)projectsontopicssuchasoceanwaveenergy,lithium-airfuelcellcatalysis,chemicallydriventhermo-powerwaves,andportablelightandpowertextilesforthedevelopingworld.FundingforMITEIUROPprojectsis
providedbyprivatedonorsandbyMITEImembers,includingFoundingMemberBPandindividualAffiliatememberswithaparticularinterestinsupportingundergraduateresearch.Formoreinformationonthesummer2010participantsandprojects,gotoweb.mit.edu/mitei/docs/education/urop/project-descriptions-2010.pdf.
Autumn 2010 | MIT Energy Initiative | Energy Futures | 27
First week on campus energizes freshmen
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participantsinmitei’s2010freshmanpre-orientationprogramcalleddiscoverenergy:learn,think,apply.
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Designawindturbine.Negotiateclimatechangewithleadersofthedevelopingworld(insimulatedfashion).Makefastfriendsbyworkingcloselywithpeopleyoubarelyknow.DiscoverhowmuchenergyMITsaveswhenpeopleuserevolvingratherthanconventionaldoors.
Numerousdoorswereopened—physically,socially,andconceptually—forthe24incomingfreshmenenrolledinaFreshmanPre-OrientationProgramcalledDiscoverEnergy:Learn,Think,Apply.HeldbytheMITEnergyInitiativeduringthelastweekinAugust2010,“DELTAFPOP”treatedstudentsto
provocativelecturesfromworld-classexperts,intriguingcampustours,andanarrayofhands-onactivities.Theresultofthistotalimmersion?Adeeperunderstandingofthechallengesandopportunitiesofenergyandclimatechange—andachancetogetajump-startonestablishingnewfriendshipsbeforeclassesevenstarted.
Tointroducethestudentstotheregiontheynowcallhome,thescheduletookthemtodiverseBostonlocales,rangingfromtheStateHouseandMuseumofSciencetoBostonHarborandtheCharlesRiver.Accordingtoparticipants,
however,oneoftheweek’smostimpressivefeatureswasitscampusfocus,wherethestudentsliterallyfollowedtheInstitute’senergyflow,fromgenerationanddistributiontoconversionandend-useconsumptionintheelectricaloutlets,switches,andhotwaterfaucetsuseddailybytheMITcommunity.AfterstoppingtostudyBuilding32’selectricalandmechanicalrooms,thegrouptracedsteam,water,andelectricitypathsthroughundergroundandoverheadconduitstoMIT’scogenerationplant.Theirtourendedonthe8thfloorofBuilding36,wheretheygotabird’s-eye
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glimpseofthecentralutilityfacility.Alongtheway,theylearnedabouttheenergylossesassociatedwithvariousdistributionnetworks—throughuninsulatedpipes,leaks,andmostconspicuously,theaging,maintenance-intensivesteamsystem.Bygettinganin-the-trencheslookatthecampus-wideenergysystem,thestudentscametounderstandasmall-scaleanaloguetothecountry’sfull-scaleenergyinfrastructure.
“Welearnedaboutthetechnologies—whatworks,whatdoesn’t,whatneedstobeimproved,andwhatMITisdoingaboutthem,”saysFPOPparticipantKellySnyder,fromAlaska.“MIThasa‘walk-the-talk’approach,tryingtodecreaseitsownenergyconsumption,whichIthinkisverycool.”
Thestudentsalsogainedamorerobustviewofalternativeenergy,supplement-ingtheirgeneralunderstandingofitspotentialbenefitswithnewinsightsonitslesser-knownlimitations,suchasenergy-storageissues.“Itwasscarybutinterestingtolearnthere’sareallylongwaytogowithallthesealternativeenergies,”saysSnyder.“ThepossibilitythatIcanbepartofthesolutiontoenergystorageandalternativeenergyisinvigorating.”
Thedifficultiesoffindingsolutions,especiallyonaglobalscale,werebroughthomeinaninteractiveclimatenegotiationsimulation.Studentsrole-playedthestancesofselecteddevelopedanddevelopingcountriesaswellassmallislandnations.Negotia-tionswereinformedbynumerousfactors—emissionreductiontargets,deadlinesforthosecuts,financialsumscountrieswouldinvestinadevelopmentfund—allofwhichwerepluggedintotheC-LEARNmodel,aweb-accessibleinternationalsimulation
developedbyateamledbyJohnSterman,theJayW.ForresterProfessorofManagement.Thesimulationhelpsusersunderstandthelong-termclimateimpactsofvariousparametersusingeasilycomprehendedgraphicaldisplays.
“Wesawhowournegotiatingtermswouldactuallyaffecttheenvironment,”explainsFPOPparticipantAnvishaPai,a17-year-oldfromMumbai,India.“Ithelpedusseehowdifficultitistocomeupwithacomprehensivesolution,andhowandwhyglobalpoliticshasbeensoinefficientinslashingemissions.”
Thelocalsideofenergypoliticswasalsodramaticallyspotlighted.Studentswereintroducedtothecollectiveimpactofleavinglightson,keepingelectronicspluggedin,andnotusingrevolvingdoors.“Lettingpeopleknowhowtodecreaseourownpersonalconsumption—itmadememoreexcitedtocometoaplacewhereallthisisgoingon,”saysSnyder,addingthattheFPOPexperience“wasmyfirstexposuretopeoplewhocareaboutthesekindsofcriticalthings,whichotherpeoplefindnerdyordorky.It’simportanttoseethatasateenagerit’sOKtobeinterestedinenergy,ratherthangoingtothemall.Itwasrefreshing.”
ForPai,theDELTAFPOPwassimilarlyeye-opening.Inadditiontolearninghowtoworkbetterinaculturallydiversegroupandunderstandingthatsheneeds“tofocusequallyhardonsocialsciencesasonengineering,”Paisaysshecametoafewrealizations.Oneconcernsherfuture—“I’mdefinitelygoingforwardwithenergyworkandresearch.”Anotherisaboutherfellowstudents.“IthoughtAmericankidswouldbeverydifferentfromme,butwe’reallonthesamepage.Beforecominghere,theonly
thingIknewaboutMITwasthatit’sanumber-oneuniversity.Iwasawedthinkingthere’salwayssomeonesmarterthanyou.”DELTAFPOPtookawayherintimidationfactor.FifteendaysafterarrivingintheUnitedStates,Paisays,“DELTAFPOPhelpedmefeelthatMITismorelikehome.”• • •
By Orna Feldman, MITEI correspondent
Autumn 2010 | MIT Energy Initiative | Energy Futures | 29
Aiming at campus energy savings, hitting the targets
ThreenewinitiativesatMITaretakingaimatenergysavingsfrommultipledirections.Thegoal:savingtensofmillionsinenergycosts,reducingtheInstitute’scarbonfootprint,andforgingnewpartnershipsthatencourageandrewardstrategicenergyuse.Sofar,thenewprogramsareallhittingtheirtargets.
Fast forward to savings
MassachusettsgasandelectricutilityNSTARandMIThaveembarkedonwhattheutilityhasdubbeditsmostaggressiveefficiencyprojecttodate.
TheMITEfficiencyForwardprogramaimstosaveupto$50millioninenergycostsoveraperiodof10years.Upgradestoheating,ventilation,andairconditioning(HVAC),electricalsystems,andlightingareexpectedtosetthestageforthelong-termsavingsbycuttingelectricaluseby15%overthenextthreeyears.
“WhatwearelaunchingwithMITisaboldnewplanforconfrontingclimatechangeandaproposaltoofficiallyestablishenergyefficiencyasthe‘firstfuel’inMassachusetts,”saidNSTARpresidentandCEOTomMaywhentheinitiativewasannouncedinspring2010.
MIT’sgoaloverthenextthreeyearsistoconserve34millionkilowatt-hours(kWh)—theequivalentelectricaluseof4,500Massachusettshomesinayear.MIT’scurrentaverageelectricityconsumptionisaround18millionkWhpermonth.TheInstituteismakingrapidprogresstowardthisyear’sgoalofsaving10millionkWh.Todate,theInstitutehassaved7.7millionkWhthroughitsEfficiencyForwardprogram,includingcompletionofseveralnewlightingretrofitprojectsinbuildingsinthenorthwestsectionofcampus;
thecompletionofseveralnewbuildingprojects,includingtheSloanSchoolofManagementbuilding;achillerplantexpansion;andotherprojectsthatincludeefficiencyenhancements.
“Wehaveover2millionkilowatt-hoursofprojectsintheplanningstage,andweexpecttomeetorexceedour2010goal,”saidWalterE.Henry,directorofthesystemsengineeringgroupfortheDepartmentofFacilities.The$50millioninsavingswillbeachievedoverthelife-timeoftheprojects,NSTARandMITsaid.
AccordingtoStevenM.Lanou,MIT’sdeputydirectorforenvironmentalsustainability,lightingretrofitsareexpectedtocontributeabouthalfthesavingsandnewconstructionfeaturesabout20%.ImprovementstoHVACandcoolingandcompressedairsystems—aswellasbehaviorchangemeasures—areexpectedtoroundoutthebalance.ThecompanywillworkwithMITtoconductHVAC,electrical,andlabsystemsimprovements,andlightingfixtureandcontrolupgrades,inadditiontoothersteps.
SeveralfactorsmadeMITanespeciallypromisingpartnerforNSTAR,accordingtoLanou.Amongthosefactorsareanewlyestablishedrevolvingfundforcampusenergyandefficiencyprojects;asetofpilotprojectsestablishedlastyear;andadisciplined,long-termenergymanagementprogramwitharobustmeasurementandverificationcomponentforenergysavings.
Witha$1milliongiftfromJeffreySilverman‘68inApril2009,theInstituteestablishedtheSilvermanEvergreenEnergyFundtosupportcampusenergyandefficiencyprojectsthathaverapidpaybacks.DavidDesjardins‘83,aconsultantandinvestorwhoisalso
passionateaboutcampusenergyissues,hassincedonatedanadditional$500,000totheeffort.
Todate,thefundhaspaidtoupgradethelightingsystemsintheRayandMariaStataCenterforComputer,Information,andIntelligenceSciences,aswellasintheStrattonStudentCenter.Thetwoprojectsrequiredacombinedinvestmentofnearly$600,000andhaveresultedinestimatedannualsavingsofabout$185,000,meaningtheywillhavepaidforthem-selvesafteraboutthreeyears.
Inaddition,theSilvermanfundallocated$430,000torecalibrateandimprovetheefficiencyofthenearly200fumehoodsintheDreyfusChemistryBuilding(Building18).Fumehoodsareenergy-intensiveventilationdevicesthatprotectresearchersfromchemicalfumes.Theyworkwellatlowerflowvolumes,savingabout$160,000annually.
The ups and downs of megawatts
In1995,MITinstalledanaturalgas-firedcogenerationplantthatprovideselectricity,steamheat,andchilledwatertomorethan100campusbuildings.Bygeneratingmuchofitsownpower,MITcutscostsandreducespollution,butoperatingtheplantrequiresa
mit’schillerplantexpansionhasaddedtwo2,500-tonhigh-efficiencychillersinotherwiseunusablespaceoverarailroadright-of-way.here,oneofthechillersisloweredintoplacebya600-toncrane.
c a m p u s e n e r g y a c t i v i t i e s
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30 | Energy Futures | MIT Energy Initiative | Autumn 2010
c a m p u s e n e r g y a c t i v i t i e s
decision-makingprocesssimilartothatusedinrunningfull-scaleutilities.
Thecogenerationfacilityprovides21megawattsofelectricityplusheatingandcoolingtomeetabout75%ofcampusenergyneeds.Fortheremain-ing25%,MITbuyselectricityfromNSTAR.Butwithenergypricesconstantlyfluctuating,itcanbedifficulttofigureoutwhenit’smorecost-effectiveforMITtobuyelectricityfromthegridortoproduceitsown.
EnterICETEC,Industrial/CommercialEnergyTechnologies.Earlierthisyear,MITcontractedwiththePennsylvania-basedcompanytotestaserviceandsoftwarepackagedesignedtoincreasetheplant’seffectivenessandmanagetheeconomicrisksassociatedwithbeingyourownutility.
ICETEChasprovidedMITwithacomputerserverthroughwhichpeoplelikeplantengineerSethKindermanconnectthroughawebinterfacethatpresentsgrapheddatafrommultiplesources.Usingdatafromtheplant’sowncontrolcenter,itshowshowmanymegawattstheplantisproducing,whichchillersarerunning,andthecurrentload.Itpredictshowtheweathermayboostelectricitycosts,stressthegrid,andcreatecongestioninenergydelivery.
“Ifit’sgoingtogethotter,consumersaregoingtousemoreelectricity,andcostsaregoingtogoup,”Kindermansaid.“ICETECmakesrecommendationstousonhowweshouldruntheplant.
“Before,wehadtoruntheturbineonthehighestoutput—setitandforgetit,sotospeak.Ifthecampusloaddropped,weproducedless.Ifitwentup,weproducedmore.
“Butthereisahugevariationinelectric-ityprices.Amegawatt-hourcouldcost$300,$30,or$5,dependingondemandandtimeofdayornight.TheICETECsoftwaretellsuswhentoproducemoreorless,whetherit’scheapertomakechilledwaterforairconditioningusingsteamorelectricity.Ifelectricitypricesarehigh,werunallsteam.Itsetsupakindofbattingorderforthechillers,soweusethemostcost-effectiveunitfirst,andsoon.”
“Becauseittellsuswhichunitismostefficienttorun,thesystemsavesMITenergyaswellasmoney,”hesaid.
ICETEC’sreal-timemonitoringofenergypricesandloadlevelsoncampusandintheregionhelpsdictatewhenMITshouldrunthecogenerationplantandwhentobuypowerfromthegridformaximumefficiency.Thenumbersarenotyetin,butthecollaborationlookspromising.”Weknewhistoricallywhatwewouldhavedoneinaparticularmonth.RoughnumbersareshowingsignificantsavingssincewepartneredwithICETEC,”Kindermansaid.
Partnering globally
Movingbeyondcampus,MIThassignedontopilotanewpublic-privatepartnershipaimedatcuttingenergyuseandgreenhousegasemissionsatindustrialandcommercialfacilities—includingacademicinstitutions—aroundtheworld.
Initially,MITwilljoineightcompaniestopilottheprogram,whichemergedfromtheCleanEnergyMinisterialpublicforumheldinWashington,DC,inJulyhostedbyUSDepartmentofEnergySecretaryStevenChu.Corporateleadersandmorethan26energyministersandsecretariesofenergyfromaroundtheworldattended,andmanyspoke
attheevent,whichlaunchedthepartner-shipcalledtheGlobalSuperiorEnergyPerformance(GSEP)Partnership.
ThroughGSEP,institutionssuchasMITcanwinglobalcertificationandrecognitionbyadoptingapprovedenergymanagementsystems.Thegoalistoachievesignificantandindependentlyvalidatedefficiencyimprovementsovertime.
GSEPcertificationwillbepilotedincommercialbuildingsbyClevelandClinic,Grubb&EllisCo.,MarriottInternationalInc.,Target,andWalmart;inindustrialfacilitiesby3MCo.,Nissan,andDowChemical;inpublicbuildingsbytheUnitedStatesandCanada;andinaneducationalsettingbyMIT.
“Toachievecertification,institutionsandindustrymustimplementanenergymanagementstandardtoidentifypathwaystoreduceenergyuse,”saidHenry.GSEP-certifiedfacilitiesalsoneedtodemonstratealevelofenergyperformanceimprovementthatexceedsbusiness-as-usuallevels.What’smore,reachingtheirtargetswillneedtobevalidatedbyanaccreditedthirdparty.
“MIT’sbeingselectedbySecretaryChuandtheDepartmentofEnergyastheonlyuniversityinvitedtohelpdevelopthisnewinternationalenergyperformancestandard,aswellasourpartnershipwithNSTAR,speaksvolumesabouttheleadershippositionMITisestablishingincampusenergymanagement,”saidLanou.“Itisourgoaltoshareourexperiencethroughthisprogramandourotheractivitiestoshowotheruniversitieswhatispossible.”
• • •
By Deborah Halber, MITEI correspondent
Autumn 2010 | MIT Energy Initiative | Energy Futures | 31
MIT study confirms natural gas as bridge to low-carbon future
o u t r e a c h
Naturalgaswillplayaleadingroleinreducinggreenhousegasemissionsoverthenextseveraldecades,largelybyreplacingolder,inefficientcoalplantswithhighlyefficientcombined-cyclegasgeneration.That’stheconclusionreachedbyacomprehensivestudyofthefutureofnaturalgasconductedbyanMITstudygroupcomposedof30MITfacultymembers,researchers,andgraduatestudents.Thefindings,summarizedinan83-pagereport,werepresentedtolawmakersandsenioradministrationofficialsinWashingtoninlateJune.
Thetwo-yearstudy,managedbytheMITEnergyInitiative(MITEI),examinedthescaleofUSnaturalgasresourcesandthepotentialofthisfueltoreducegreenhousegas(GHG)emissions.Basedontheworkofthemultidisci-plinaryteam,withadvicefromaboardof16leadersfromindustry,govern-ment,andenvironmentalgroups,thereportexaminesthefutureofnaturalgasthrough2050fromtheperspectivesoftechnology,economics,politics,nationalsecurity,andtheenvironment.
Thereportincludesasetofspecificproposalsforlegislativeandregulatorypolicies,aswellasrecommendationsforactionsthattheenergyindustrycanpursueonitsown,tomaximizethefuel’simpactonmitigatingGHGs.Thestudyalsoexaminedwaystocontroltheenvironmentalimpactsthatcouldresultfromasignificantexpansionintheproductionanduseofnaturalgas—especiallyinelectricpowerproduction.
“Muchhasbeensaidaboutnaturalgasasabridgetoalow-carbonfuture,withlittleunderlyinganalysistobackupthiscontention.Theanalysisinthisstudyprovidestheconfirmation—naturalgastrulyisabridgetoalow-carbonfuture,”
saidMITEIDirectorErnestJ.Monizinintroducingthereport.
Monizfurthernoted,“Intheverylongrun,verytightcarbonconstraintswilllikelyphaseoutnaturalgaspowergenerationinfavorofzero-carbonorextremelylow-carbonenergysourcessuchasrenewables,nuclearpower,ornaturalgasandcoalwithcarboncaptureandstorage.Forthenextseveraldecades,however,naturalgaswillplayacrucialroleinenablingverysubstantialreductionsincarbonemissions.”
Twomajorfactorsthatcanmakeasignificantdifferenceinthenearterminreducingcarbonemissionsareusinglessenergyandusinggasinsteadofcoal—especiallybyreplacingtheoldest,least-efficientcoalplantswiththemost-efficientmoderncombined-cyclegasplants,saidMoniz,whochairedthestudyalongwithco-chairsHenryJacoby,professorofmanagement,andTonyMeggs,MITEIvisitingengineer.
Thestudyfoundthattherearesignificantglobalsuppliesofconventionalgas.HowmuchofthisgasgetsproducedandusedandtheextentofitsimpactonGHGreductionsdependcriticallyonsomekeypoliticalandregulatorydecisions.
IntheUnitedStates,forexample,thereisasubstantialamountoflow-hangingfruitavailablebydisplacinginefficientpowergenerationwithmoreefficient,lowercarbondioxide(CO2)emittinggasplants.“Thatkindofsubstitutionalone,”Monizsaid,“reducesthosecarbonemissionsbyafactorofthree.Itdoes,however,raisecomplicatedregulatoryandpoliticalissuesthatwillhavetoberesolvedtotakeadvantageofthispotential.”
Some key findings
1. TheUnitedStateshasasignificantnaturalgasresourcebase,enoughtoequalabout91years’worthofsupplyatpresentdomesticconsumptionrates.Muchofitisfromunconventionalsources,includinggasshales.Whilethereissubstantialuncertaintysur-roundingtheproducibilityofthisgas,thereisasignificantamountofshalegasthatcanbeaffordablyproduced.
Globally,baselineestimatesshowthatrecoverablegasresourcesprobablyamountto16,200trillioncubicfeet(Tcf)—enoughtolastover160yearsatcurrentglobalconsumptionrates.Further,withtheexceptionoftheUSandCanada,thisglobalresourcefiguredoesnotincludeanyunconventionalgasresources,whicharelargelyuncharacterizedintherestoftheworld.TheMiddleEast,Russia,andtheUShavethehighestconcentrationofglobalgasreserves(seethefigureonpage32).
IntheUS,unconventionalgasresourcesarerapidlyovertakingconventionalresourcesastheprimarysourceofgasproduction.TheUScurrentlyconsumesaround22Tcfperyearandhasagasresourcebasenowthoughttoexceed2,000Tcf.
Tobringaboutthekindofsignificantexpansionintheuseofnaturalgasidentifiedinthisstudy,substantialadditionstotheexistingprocessing,delivery,andstoragefacilitieswillberequiredinordertohandlegreateramountsandthechangingpatternsofdistribution(suchasthedeliveryofgasfromnewlydevelopedsourcesintheMidwestandNortheast).
2. Environmentalissuesassociatedwithproducingunconventionalgasresourcesaremanageablebut
32 | Energy Futures | MIT Energy Initiative | Autumn 2010
o u t r e a c h
challenging.Risksincludeshallowfreshwateraquifercontaminationwithfracturefluids,surfacewatercontaminationbyreturnedfracturefluids,excessivedemandonlocalwatersupplyfromfracturingoperations,andsurfaceandlocalcommunitydisturbanceduetodrillingandfractur-ingactivities.
3. Naturalgasconsumptionwillincreasedramaticallyandwilllargelydisplacecoalinthepowergenerationsectorby2050(thetimehorizonofthestudy)underamodelingscenariowhere,throughcarbon-emissionspricing,industrializednationsreduceCO2emissionsby50%by2050andlargeemergingeconomies,e.g.,China,India,andBrazil,reduceCO2emissionsby50%by2070.Thisassumesincrementalreductionsinthecurrentpricestructuresofthealterna-tives,includingrenewables,nuclear,andcarboncaptureandsequestration.
4.Theintroductionoflargeintermittentpowergenerationfrom,forexample,windandsolarwillhavespecificshort-andlong-termeffectsonthemixofgenerationtechnologies.Theshort-termeffects(meaningdailydispatchpatternsofvariousfuels)oflargeamountsofwindgeneration,forexample,willreducegasgenerationsignificantlyandcouldforcebaseloadcoalplantstocycle,anoutcomethatishighlyunde-sirablefromanoperationalperspective.
Inthelongerterm,thereliabilityofasysteminwhichrenewablesassumeabaseloadroleinpowergenerationwillrequireadditionalflexiblenaturalgaspeakingcapacity,althoughthiscapacitymaybeutilizedforonlyshortperiodsoftime.Renewablesasbaseloadpower,firmedbynaturalgasgeneration,willrequirenewregulatorystructurestoensurereliabilityofthesystem
andincentivizethebuildingofflexiblegascapacity.
5.Theoverbuildingofnaturalgascombined-cycle(NGCC)plantsstartinginthemid-1990spresentsasignificantopportunityfornear-termreductionsinCO2emissionsfromthepowersector.ThecurrentfleetofNGCCunitshasanaveragecapacityfactorof41%,relativetoadesigncapacityfactorofupto85%.However,withnocarbonconstraints,coalgenerationisgenerallydispatchedtomeetdemandbeforeNGCCgenera-tionbecauseofitslowerfuelprice.
ModelingoftheERCOTregion(largelyTexas)suggeststhatCO2emissionscouldbereducedbyasmuchas22%withnoadditionalcapitalinvestmentandwithoutimpactingsystemreliabilitybyrequiringadispatchorderthatfavorsNGCCgenerationoverinefficientcoalgeneration;preliminarymodelingsuggeststhatnationwideCO2emissionswouldbereducedbymorethan10%.Atthesametime,thiswouldalsoreduceairpollutantssuchasoxidesofsulfurandnitrogen.
6.Inthetransportationsector,thestudyfoundasomewhatsmallerrolefornaturalgas.TheuseofcompressedorliquefiednaturalgasasafuelforvehiclescouldhelptodisplaceoilandreduceGHGemissionsbuttoalimitedextentbecauseofthehighcostofconvertingvehiclestousethesefuels.Bycontrast,makingmethanol,aliquidfuel,outofnaturalgasrequiresmuchlessup-frontconversioncostandcouldhaveanimpactonoilusageandthusimproveenergysecurity,butwouldnotreduceGHGs.
7. Aglobal“liquid”marketinnaturalgasinwhichsupplysourcesarediverseandgaspricesaretransparent,setbysupplyanddemandwithpricediffer-encesbasedontransportationcosts,isdesirableforUSconsumers.
Therearecurrentlythreeregionalgasmarkets—NorthAmerica,Europe,andAsia—whichhaveverylittleintegrationandrelyoncompletelydifferentpricingstructures.ModelingsuggeststhattheintegrationofthesemarketswouldresultinsubstantiallylowerpricesforUSconsumers.
Trillion cubic feet (Tcf) of gas 0 1,000 2,000 3,000 4,000 5,000 6,000
Middle East
Russia
United States
Africa
Rest of Europe and Central Asia
Canada
Rest of Americas
Europe
Dynamic Asia
Brazil
Rest of East Asia
Australia & Oceania
China
India
Mexico
0 1000 2000 3000 4000 5000 6000
0.0
0.2
0.4
0.6
0.8
1.0
Middle East
Russia
United States
AfricaCentral Asia and
Rest of Europe Canada
Rest of Americas
EU and Norway
Dynamic Asia
Brazil
Rest of East Asia
Australia & Oceania
China
Mexico
India
Reserve growth (mean)
Proved reserves
Yet-to-�nd resources (mean)
Unconventional resources (mean)P90RRR
P10RRR
Remaining recoverable natural gas resources(excludesunconventionalgasoutsideNorthAmerica)
definitions:“resource”referstothesumofallgasvolumesexpectedtoberecoverableinthefuture,givenspecifictechnologicalandeconomicconditions.resourceisdisaggregatedintothefollowingsubcategories:provedreserves,reservegrowth(viafurtherdevelopmentofknownfields),andyet-to-findresources(gasvolumesthatwillbediscoveredinthefutureviatheexplorationprocess).
uncertaintybars:thereisa90%chancethatthetruevalueofremainingrecoverableresources(rrr)isgreaterthanthelowerendoftheuncertaintybar(p90)anda10%chancethatitisgreaterthantheupperend(p10).
Autumn 2010 | MIT Energy Initiative | Energy Futures | 33
o u t r e a c h
Recommendations
Thestudymakesmanyrecommenda-tionsregardingtheroleofnaturalgasinacarbon-constrainedworld,suggestingthatpolicymakersshouldconsidersupportivepoliciesinthefollowingareas.
Supply• Requiredisclosureofallcomponents
ofhydraulicfracturefluids.
• Requireintegratedregionalwaterusage/disposalplansforunconven-tionalgasproduction.
• SupportarenewedDepartmentofEnergy(DOE)R&Dprogramweightedtowardbasicresearchandan“off-budget”industry-ledprogramweightedtowardtechnol-ogydevelopment,demonstration,andtransfer.Programsshouldbedesignedtooptimizegasresourcesandensurethattheyareproducedinenvironmentallysoundways.
Power generation• Pursuedisplacementofinefficientcoal
generationwithNGCCgeneration.
• Developpolicyandregulatorymea-surestofacilitatenaturalgasgenera-tioncapacityinvestmentsconcurrentwiththeintroductionoflargeintermit-tentrenewablegeneration.
Transportation• Removepolicyandregulatory
barrierstonaturalgasasatranspor-tationfuel.
Global markets• Supportpoliciestofosteraninte-
gratedglobalgasmarket,includingtheintegrationofnaturalgasissuesintotheforeignpolicyapparatus,withstronginvolvementoftheExecutiveOfficeofthePresidentsupportedbyastrengthenednaturalgaspolicyapparatusatDOE.
• ExportUSknowledgeinunconven-tionalgascharacterizationandproductiontonationsthatcanadvanceUSstrategicinterests.
WhilethenewreportemphasizesthegreatpotentialfornaturalgasasatransitionalfueltohelpcurbGHGemissionsanddependenceonoil,italsostressesthatitisimportantas
20.00
18.00
16.00
14.00
12.00
10.00
8.00
6.00
4.00
2.00
0
Trillion cubic feet (Tcf) of gas
Brea
keve
n ga
s pr
ice*
($/m
illio
n Bt
u)
0 4,000 8,000 12,000 16,000 20,000
P90MeanP10
Sample LNG value chaincosts incurred during gas delivery**
$/million BtuLiquefaction $2.15Shipping $1.25Regasi�cation $0.70
Total $4.10
0
5000
10000
15000
20000
0.0
0.2
0.4
0.6
0.8
1.0
P9012,400
P1020,800
Volumetric uncertainty aroundmean of 16,200 Tcf
Lique�ed natural gas (LNG) manufacturing and transportation costs add to the breakeven gas price.
amatterofnationalpolicynottofavoranyonefuelorenergysourceinawaythatputsothersatadisadvantage.Themostusefulpolicies,theauthorssuggest,areonesthatproduceatruly“levelplayingfield”forallformsofenergysupplyandfordemandreduction,andthusletthemarketplaceandtheingenuityofthenation’sresearchersdeterminethebestoptions.
Illustratingtheroleofnaturalgasasabridgetoalow-carbonfuture,thestudy’sauthorsstressthatitwouldbeamistaketoletnaturalgascrowdoutresearchonotherlow-orno-carbonenergysources,butitwouldalsobeamistaketoletinvestmentsinsuchalternativescrowdouttheexpansionofnaturalgasresourcesinthenearterm,particularlyforthepurposesofCO2emissionsmitigation.
“Inacarbon-constrainedworld,naturalgaswillbecomealargerpartoftheenergymix,”Monizsaid.Butinthelongerterm,itwillbenecessarytoshiftto“essentiallyzero-carbon”sources,so“webetternotgetmesmerizedbygaseither.Weneedtodothehardworkofgettingthosealternativetechnologiesreadytotakeover.”
• • •
By Melanie A. Kenderdine, MITEI, and David L. Chandler, MIT News Office
This study received support from the American Clean Skies Foundation, Hess Corporation, Agencia Nacional de Hidrocarburos of Colombia, and the Energy Futures Coalition and the MIT Energy Initiative. The report issued is a preliminary overview of a more detailed report that will be released later this year. To download a pdf of the interim report, go to web.mit.edu/mitei/research/studies/naturalgas.html.
Global gas supply curve(excludesunconventionalgasoutsideNorthAmerica)
*2007costbase.northamericanbreakevenpricesarecalculatedatthewellhead;forregionsoutsidenorthamerica,breakevenpricesarecalculatedatthepointofexport.breakevenpricescalculatedusing10%realdiscountrateandicfhydrocarbonsupplymodel.
**assumestwo4millionmetrictonlngtrainswithabout6,000-mileone-waydeliveryruns,perJensenandassociates.excludescostofthegas.
34 | Energy Futures | MIT Energy Initiative | Autumn 2010
MITEI releases report on critical elements for new energy technologies
o u t r e a c h
Thestrategicimportanceofrareearthelementswasoneofseveralissueshighlightedinarecentreport, Critical Elements for New Energy Technologies,releasedbytheMITEnergyInitiative(MITEI)anditsco-sponsors,theAmericanPhysicalSociety’sPanelonPublicAffairsandtheMaterialsResearchSociety.Thereportsumma-rizesthesixcommissionedwhitepapers,presentations,anddiscussionsattheApril29workshopheldatMITEIheadquartersontheMITcampus.
Rareelementsarecriticalforadvancedmanufacturingof,forexample,photovoltaics,superconductors,high-performancepermanentmagnets,batteries,keycatalysts,hybridcarcomponents,andcompactfluorescentlights.Elementssuchasgallium,indium,lanthanum,lithium,neodym-ium,tellurium,andterbiumarenowroutinelypartofthediscussionaboutnovelenergytechnologies,butmanyoftheseelementsarenotatpresentmined,refined,ortradedinlargequantitiesandcouldpresentscale-upchallenges.
Theworkshop,co-chairedbyRobertJaffe,theMorningstarProfessorofPhysicsatMIT,andJonathanPrice,thestategeologistofNevadaandprofessorattheUniversityofNevada,Reno,examinedhowgeologic,technical,socioeconomic,political,andeconomicfactorsmightlimitconsumeraccesstothesemineralsandtheimplicationsforthemanufacturinganddeploymentofnewenergytechnologies.
Someoftheconclusionsinthereportare:
• Manynoveltechnologiesaremateri-alsintensiveandifwidelydeployedwillcompetewithotherusesofrareelements.
• Chinahasemergedasaprimaryproducerofenergy-criticalelementsandhaslessstringentenvironmentalrequirementsformining/production.Thereareconcernsaboutmonopolyandaccessrestrictions,especiallybecausesubstitutionopportunitiesforrareearthsinenergy-criticalapplicationsarelimited.Chinanowmeetsmorethan95%oftheworld’sdemandforrareearths.
• Therearenewpotentialsourcesofrareelements,buttheyareusuallyexpensiveandtechnicallychallengingtodevelopandproduce.Researchanddevelopmentisneeded.
• Thelongleadtimesof5to15yearsfornewminingventurescouldleadtoshortagesandpricespikes.
• Thecadmiumtelluridephotovoltaicindustrycurrentlyhasanannualgrowthrategreaterthan100%.Ifsuppliesoftelluriumobtainedasby-productsofcopperproductionproveinsufficient,othersourcescanbebroughtintoplay,buttheassociatedtimeconstantsarehardtopredict.
• TheUnitedStatesneedstransparent,accuratedataonproduction,reserves,andreservebasesforenergy-criticalelements.TheUSGeologicalSurveyshouldberesourcedtoconductacomprehen-siveestimateofthereservebasesforthoseelements.
• Thepublicandpolicymakersnowhavelimitedawarenessofthemineralfootprint,similartotheearlieststagesoftheenvironmentalmovement.RaisingawarenessisimportantfortheconservationoftheserarematerialsaswellasfortheassociatedrecyclingandR&Dthatareneededtomeetgrowingdemand.
Todownloadacopyofthereport,pleasegotoweb.mit.edu/mitei/research/energy-studies.html.
• • •
By Melanie A. Kenderdine, MITEI
Autumn 2010 | MIT Energy Initiative | Energy Futures | 35
MITEI seminars and colloquia
o u t r e a c h
MITEI Seminar Series, 2010–2011
October 12, 2010Mitigating manhole events in ManhattanCynthiaRudin,AssistantProfessorofStatistics,MITSloanSchoolofManagement
November 9, 2010 Solar photovoltaic materials, processes, and devicesTonioBuonassisi,AssistantProfessor,MechanicalEngineering,MIT
December 14, 2010Response to the Gulf oil spill and the larger issue of energy and national securityJulietteKayyem,AssistantSecretaryforIntergovernmentalAffairs,USDepartmentofHomelandSecurity
February 8, 2011Decision making in electricity markets and control problems of large energy systemsMarijaIlic,Professor,ElectricalandComputerEngineering,CarnegieMellonUniversity
March 8, 2011 Organic semiconductors, nanostructures, and solar cellsMichaelMcGehee,AssociateProfessor,MaterialsScienceandEngineering,StanfordUniversity
April 12, 2011Catalysis for hydrogen productionClausHviidChristensen,LindoeOffshoreRenewablesCenter,Denmark
May 10, 2011Catalysis and surface chemistryMarcKoper,Professor,Chemistry,LeidenUniversity,TheNetherlands
onoctober15,georgep.shultzphd’49,chairofmitei’sexternaladvisoryboard,discussednucleardisarmamentafterascreeningofthedocumentaryfilmNuclear Tipping Point.inthefilm,formersecretariesofstateshultzandhenryKissinger,formersecretaryofdefensewilliamperry,andformersenatorsamnunncallforthecompletedisarmamentoftheworld’snucleararsenals—astancemotivatedbytheriseofterrorismcombinedwiththeanticipatedspreadofweaponsmaterials,whichcouldbewidelyproducedthroughtheinternationalreprocessingofnuclearreactorspentfuel.theeventwasco-sponsoredbymiteiandthemitcenterforinternationalstudies.
duringamiteicolloquiumonoctober13,arunmajumdar,directoroftheusdepartmentofenergy’sadvancedresearchprojectsagency-energy(arpa-e),discussedtheglobalenergychallengeandtherolehisagencyplaysintryingtofostertransformationalenergyresearchanddevelopment.majumdar’spresentationtoastanding-room-onlycrowdservedasbothawake-upcallandasourceofinspiration.henotedthattheusspendsmoreondogfoodr&dthanonelectricalpowerr&d.healsodiscussedsomeoftheveryrealandexcitingenergyprojectshisagencyisfunding,includingseveralatmit.
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36 | Energy Futures | MIT Energy Initiative | Autumn 2010
Martin Fellows explore the changing coastal environment
l f e e • laboratoryforenergyandtheenvironment
InSeptember2010,MartinFellowsforSustainabilityspentaweekendretreatatPlumIsland,an11-mile-longbarrierislandofftheshoreofNewburyport,Massachusetts.TheislandishometotheParkerRiverNationalWildlifeRefuge,a4,662-acresanctuarythatprovidesfeeding,resting,andnestinghabitatformigratorybirds.Thefellowslearnedaboutbirdmigrationstrategiesandhowtheyareimpactedbychangingenvironmentalconditions.MassachusettsAudubonSociety’sJoppaFlatsEducationCenterstaffandvolunteersledtheweekend’sactivities.
left:retreatattendeesspottedgreatblueheronsandotherwildlifeduringarivercruisethatmeanderedthroughmilesoftherefuge’sgreatmarsh.
below:birdscaughtattheJoppaflatsbandingstationaretaggedwiththeselightweightanklebracelets.aftergatheringdata(species,weight,age,gender)andbandingthebirds,thevolunteersreleasethemtocontinuetheirjourneys.
benflemer,manageroftheeducationcenter’sbirdbandingstation,holdsaplainswarbler.behindhimisalistofwarblerspeciesthatwerebandedatthestationinearlyfall2010.
anitaganesan,a2010martinfellowinearth,atmospheric,andplanetarysciences,looksthroughatelescopeasJoppaflatssanctuarydirectorbillgettedescribesthehabitat.
massaudubonvolunteerJohnhalleran(center)demonstrateshowtomeasuretheturbidityofriverwatertomartinfellows(fromleft)Kathyaraujo(2009),lilysong(2010),isabelleanguelovski(2008),andmadhudutta-Koehler(2010),allofurbanstudiesandplanning.
here,flemerblowsgentlytoseparateatowhee’sfeathersasmartinfellowslookon.thepinknessoftheunderlyingskinindicatesthebird’sleveloffat,whichmustsustainthemigrantasittravelshundredsorthousandsofmiles.
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Autumn 2010 | MIT Energy Initiative | Energy Futures | 37
Deutch named to Secretary of Energy Advisory Board
Herzog receives international award
o t h e r n e w s
InstituteProfessorJohnM.DeutchhasbeennamedtotheSecretaryofEnergyAdvisoryBoard(SEAB),whichwillserveasanindependentadvisorycommitteetoUSSecretaryofEnergyStevenChu,theUSDepart-mentofEnergy(DOE)announcedonAugust10,2010.
DeutchhasservedinanumberofpositionsforDOE,includingdirectorofenergyresearchandundersecretaryofthedepartment.Heservedasdirectorofcentralintelligencefrom1995to1996anddeputysecretaryofdefensefrom1994to1995.
HowardHerzog,seniorresearchengineerattheMITEnergyInitiative,hasbeenpresentedthe2010GreenmanAwardbytheInternationalEnergyAgencyGreenhouseGasR&DProgramme(IEAGHG)inrecognitionofhislongstandingnationalandinternationalcommitmenttocarboncaptureandstorage(CCS)researchanddevelopment.
AnMITstaffmembersince1989,Herzoghasfocusedhisresearchonenergyandtheenvironment,withanemphasisongreenhousegasmitigationtechnologies.In2000,hefoundedtheMITCarbonSequestrationInitiative,anindustrialconsortiumdedicatedtoinvestigatingCCStechnologies.Theinitiativenowhas18members.
AmemberoftheMITfacultysince1970,Deutchhasservedonthesix-memberMITEnergyCouncilsinceitwasformedinNovember2006tohelpguidedevel-opmentofthenewlycreatedInstitute-wideMITEnergyInitiative.AtMIT,DeutchhasalsoservedasheadoftheDepartmentofChemistry,deanofscience,andprovost.
The12-memberSEAB—consistingofscientists,businessexecutives,academics,andformergovernmentofficials—willprovideadviceandrecommendationstoSecretaryChuonDOE’sbasicandappliedresearchanddevelopmentactivities,economicandnationalsecuritypolicy,educationalissues,operationalissues,andotheractivitiesasdirectedbythesecretary.
HerzogwasacoordinatingleadauthorontheIPCC Special Report on Carbon Dioxide Capture and Storage(releasedSeptember2005),aco-authoronThe Future of Coal: An Interdisciplinary MIT Study(releasedMarch2007),andaUSdelegatetotheCarbonSequestra-tionLeadershipForum’sTechnicalGroup(June2003–September2007).
KellyThambimuthu,chairmanoftheIEAGHG,presentedtheawardtoHerzogonSeptember23,2010,duringtheInternationalConferenceonGreenhouseGasControlTechnologies(GHGT-10)inAmsterdam.Theweeklongconference,oneofthemostsignificantinthefieldofgreenhousegasemissionsreduction,attractedmorethan1,500delegatesthisyear.
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38 | Energy Futures | MIT Energy Initiative | Autumn 2010
o t h e r n e w s
MITEI External Advisory Board meets
TheMITEnergyInitiative’sExternalAdvisoryBoardmetonOctober14–15,2010.Theboard,chairedbyGeorgeP.ShultzPhD’49,formerMITfacultymemberandsecretaryofstateintheReaganadministration,meetsannuallytoprovidehigh-levelstrategicdirectionfortheinitiativeandtoreviewMIT’sprogressinenergyfields.In2010,MITEIwelcomedsevennewEABmembers:SusanEisenhower,WalterB.Hewlett,FrankE.Mars,ThomasF.McLartyIII,GülerSabanci,GeraldSchotman,andRatanN.Tata.Inaddition,MITEIwelcomedLamarMcKayrepresentingBPAmerica,Inc.,andPaoloScaronirepresentingEniS.p.A.Specialcampus-wideeventsassociatedwiththeboardmeetingfeaturedShultzandArunMajumdar,directoroftheDepartmentofEnergy’sAdvancedResearchProjectsAgency-Energy(seepage35).
Members as of November 2010
Sultan Ahmed Al Jaber ChiefExecutiveOfficer,AbuDhabiFutureEnergyCompany
Stephen D. Bechtel, Jr. Chairman,SDBechtel,Jr.FoundationandStephenBechtelFund
Frances Beinecke President,NaturalResourcesDefenseCouncil
Denis A. Bovin Co-ChairmanandCo-ChiefExecutiveOfficer,StoneKeyPartnersLLC
Rafael del Pino Chairman,GrupoFerrovialSA
Susan Eisenhower ChairmanEmeritus,EisenhowerInstitute
Arthur L. Goldstein RetiredChairmanandChiefExecutiveOfficer,IonicsIncorporated
Walter B. Hewlett Chairman,TheWilliamandFloraHewlettFoundation
Baba N. Kalyani ChairmanandManagingDirector,BharatForgeCompanyLimited
Anne Lauvergeon ChiefExecutiveOfficer,AREVA
Lawrence H. Linden FounderandTrustee,LindenTrustforConservation
Frank E. Mars President,MarsSymbioscience
Lamar McKay ChairmanandPresident,BPAmerica,Inc.
Thomas F. McLarty III President,McLartyAssociates
Robert M. Metcalfe GeneralPartner,PolarisVenturePartners
Robert B. Millard ManagingPartner,RealmPartnersLLC
Mario J. Molina Professor,UniversityofCalifornia,SanDiego
Sam Nunn Co-ChairmanandChiefExecutiveOfficer,NuclearThreatInitiative
Ngozi N. Okonjo-Iweala ManagingDirector,WorldBank
John S. Reed Chairman,MIT
Güler Sabanci ChairmanandManagingDirector,HaciOmerSabanciHoldingAS
Kenan E. Sahin PresidentandFounder,TIAXLLC
Arthur J. Samberg ChairmanandChiefExecutiveOfficer,PequotCapitalManagementIncorporated
Paolo Scaroni ChiefExecutiveOfficer,EniS.p.A.
Gerald Schotman ExecutiveVicePresidentInnovation/R&DandChiefTechnologyOfficer,RoyalDutchShellplc
Philip R. Sharp President,ResourcesfortheFuture
George P. Shultz (Chair)ThomasW.andSusanB.FordDistinguishedFellow,HooverInstitution
Robert M. Solow InstituteProfessorEmeritus,MIT
Ratan N. Tata Chairman,TataSonsLimited
James D. Wolfensohn ChairmanandChiefExecutiveOfficer,Wolfensohn&Company,L.L.C.
Daniel Yergin Chairman,IHSCambridgeEnergyResearchAssociates
Autumn 2010 | MIT Energy Initiative | Energy Futures | 39
New technologies unveiled at Eni-MIT press briefing
MIT Energy Fellows Symposium
m i t e i m e m b e r s
NewMITinnovationssuchasimprint-ingsolarcellsonpaperandamaterialthatcouldhelpcleanupoilspillswereunveiledOctober18atapressbriefingledbyMITPresidentSusanHockfieldandPaoloScaroni,CEOoftheItalianenergycompanyEniS.p.A.,afoundingmemberoftheMITEnergyInitiative.
Theeventhighlightednewjointtech-nologiescomingoutoftheEni-MITAlliance,afive-yearresearchprogramfocusingonadvancedsolarresearchandotherstrategicresearchcentraltoEni’scorebusiness,includingoilandgasproduction.
HockfieldcreditedEniwith“makingfar-sightedinvestmentsthatcouldtransformthelong-termenergyequation,”andnotedthatthealliance—formedin2008—hasresultedin18publishedstudiesandfivepatentfilingstodate.
Atthebriefing,ProfessorKarenGleasonofchemicalengineeringandassociatedeanofengineeringforresearch,reportedonarevolutionarywaytoproduceultra-lightweight,inexpensive,flexiblesolarcells.Shedemonstratedhowanindex-card-sizedsquareofordinarytracingpaperimprintedwiththesecellscouldpoweranLEDclock.“Youreallycanmakesolarcellsonpaperthatareusableandthatpoweradevice,”saidGleason.
Thenewapproach,developedbyGleasonincollaborationwithProfessorVladimirBulovicofelectricalengineer-ingandcomputerscienceandhisteam,involvesrapidlydepositingmaterialsatroomtemperatureusingonlyenviron-mentallyfriendlymethods.Withthistechnique,solarcellscouldbelayeredonrooftiles,windowblinds,orlaptops.
ProfessorPhilGschwendofcivilandenvironmentalengineeringpresented
TheMITEnergyInitiativehostedtheannualMITEnergyFellowsSymposiumatthenewMediaLaboratorybuildingonOctober27,2010.Facultypresentedresearchinsolarenergytofellowsfromthepastthreeyearsandrepresen-tativesfromtheirsponsoringcompanies.Apostersessionfollowed.
ananotech-basedmaterial—developedbyhiscollaboratorProfessorFrancescoStellacciofmaterialsscienceandengineering—thatrepelswaterbutallowsoiltopass.“It’spossiblewecancreatedevicesthat,whenoilisescaping,canrecaptureandaccumulateitsoitcanthenbepumpedintoatanker,”hesaid.
Heshowedavideoofaconeofthematerialsubmergedinabeakerofoilandwatersimulatinganoilspill.Oilpooledinthedeviceandwasremovedwithnowaterinthemixture.Gschwendsaidsuchoil-collectingdevicescouldonedaybepermanently“oncall”foremergencyuseinareassuchastheGulfofMexico.
ScaronisaidhewasimpressedwithMIT’sresearchresultsandemphasizedtheurgencyofmakingproductssuchastheoil-collectingdeviceavail-abletoaddresscatastrophessuchastheBPspillintheGulfofMexico.Thatincident“haspushedustoworkintwofields—preventionandsolutions—toprovideanswerstowhathappensifwehaveanaccident,”Scaronisaid.
• • •
By Deborah Halber, MITEI correspondent
mitprofessorKarengleason(center),withmitpresidentsusanhockfield(left),demon-strateseni-supportedresearchon“paper-thinphotovoltaics”foreniceopaoloscaroni.
evelynwang,theestherandharolde.edgertonassistantprofessorofmechanicalengineering,describesnanoengineeringofhydrophobicsurfacesforsolarthermalenergyapplications.
gaudenziomariotti,headofnuclearenergy,energyandinnovationdivision,enelproduzionespa,conferswithgiancarlolenci,2010–2011enel-mitenergyfellowinnuclearscienceandengineering.
studentsandrepresentativesofmiteimembercompaniesdiscussenergyresearchatapostersessionfeaturingprojectsfromthemiteienergyresearchseedfundprogram.
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m i t e i m e m b e r s
Latest seed grant projects supported by MITEI members
Recipients of MITEI seed grants, Spring 2010
For more information, see the article on page 21.
Energy-efficient desalination by shock electro-dialysis in porous media Martin Bazant Chemical Engineering
Energy-efficient algorithms Erik Demaine, Martin DemaineComputer Science and Artificial Intelligence Laboratory (CSAIL)
Solar energy conversion using the phenomenon of thermal transpiration Nicolas HadjiconstantinouMechanical Engineering
Synthesis of bimetallic nanoparticle structures as catalysts for fuel cellsKlavs JensenChemical Engineering
Advanced multi-core processor architectures for power electronics controls and simulation: enabling efficient integration of renewables into the smart grid John JoannopoulosPhysics Ivan CelanovicInstitute for Soldier Nanotechnologies Srini DevadasElectrical Engineering and Computer Science
Multi-functional self-assembled photonic crystal nanotexture for energy-efficient solid state lighting Lionel KimerlingMaterials Science and Engineering
Subsurface change detection for CO2 sequestration Alison Malcolm, Michael FehlerEarth, Atmospheric, and Planetary Sciences
Self-assembled polymer-enzyme nanostructures for low-temperature CO2 reduction Bradley OlsenChemical Engineering
A novel framework for electrical grid maintenance Cynthia Rudin Management
Novel bioprocess for complete conversion of carbon feedstocks to biofuels Gregory StephanopoulosChemical Engineering
Ultra-low drag hydrodynamics using engineered nanostructures for efficiency enhancements in energy, water, and transportation systems Kripa VaranasiMechanical Engineering
Nanofilm-based thermal manage-ment device for concentrated solar energy conversion systemsEvelyn Wang Mechanical Engineering
Experimental study of millimeter-wave rock ablation Paul Woskov PlasmaScienceandFusionCenter
Autumn 2010 | MIT Energy Initiative | Energy Futures | 41
M I T E I • r E s E a r C h
MITEI Founding and Sustaining members
MITEI Associate and Affiliate members
M I T E I M E M B E r s
MITEI’s Associate and Affiliate members support a range of MIT energy research, education, and campus activities that are of interest to them. Current members are now supporting various energy-related MIT centers, laboratories, and initia-tives; fellowships for graduate students; research opportunities for undergraduates; campus energy management projects; outreach activities including seminars and colloquia; and more.
Associate membersAgencia Nacional de Hidrocarburos (ANH)—Colombia CumminsDenbury Resources, Inc.EDFEntergyExelonFundació Barcelona Tecnológica (b_TEC)Hess
Affiliate membersAlbachiara Rinnovabili S.r.l.Alcatel-LucentAngeleno GroupAspen Technology, Inc.Beacon PowerBerkeley Investments, Inc.Marilyn G. BreslowBrownstein Hyatt Farber
Schreck, LLPConstellation EnergyEnerNOC, Inc.Forge Partners, LLCGabelli Capital PartnersGas Technology InstituteGravitas & Cie Int. SAGreengEnergyHarris InteractiveICF InternationalIHS Cambridge Energy
Research Associates (IHS CERA)
Paul MashikianMillennial Net, Inc.
Mohave Sun Power, LLC (Mitchell Dong)
Moore and Van AllenNew Energy FinanceNexant, Inc.NGP Energy Technology
Partners, LPNth power, LLCOrmat Technologies, Inc.
(inaugural member)Osaka Gas Co., Ltd.Palmer Labs, LLCPatriot RenewablesRedpoint VenturesPhilip Rettger
(inaugural member)Rockport Capital PartnersRopes and Gray, LLPS. Kinnie Smith, Jr.Steptoe & Johnson, LLPGeorge R. Thompson, Jr.The Tremont Group, LLCWestport Innovations, Inc.
F o u n d I n g M E M B E r s
BP (inaugural member)Eni S.p.A.Shell
F o u n d I n g P u B l I C M E M B E r
Masdar Institute
s u s T a I n I n g M E M B E r s
ABB Research Ltd.Robert Bosch GmbHChevron U.S.A. Inc.Enel Produzione SpAFerrovialLockheed MartinSaudi Aramco SchlumbergerSiemensTotalWeatherford International Ltd.
s u s T a I n I n g P u B l I C M E M B E r
Portuguese Science and Technology Foundation
Members as of December 1, 2010
MITEI’s Founding and Sustaining members support “flagship” energy research programs or individual research projects that help them meet their strategic energy objectives. They also provide seed funding for early-stage innovative research projects and support named Energy Fellows at MIT. To date, members have made possible 67 seed grant projects across the campus as well as fellowships for more than 100 graduate students in 20 MIT departments and divisions.
The sun’s rays can be highly destructive to materials, so some of the novel solar energy systems now being developed may get less efficient as they are used. Plants deal with that problem by continually disassembling and reassembling their light-gathering molecules so they’re in effect always brand new. MIT researchers have now been able to mimic that strategy. They start with a mixture of components suspended in a soapy solution (above). They then filter out one of the components, and those that remain assemble themselves into a highly ordered series of light-harvesting, electricity-producing structures (front cover). For more details on the diagram and the research, see page 4.
New photovoltaic technology
MIT Energy Initiative
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