GEOTHERMAL ENERGY Catherine Hillard Jaymie Trask Trevor Larson
Nov 02, 2014
GEOTHERMAL ENERGYCatherine Hillard
Jaymie Trask
Trevor Larson
Overview• THREE KEY ISSUES
• Geothermal Reservoirs• Geothermal Energy Production• Geothermal Energy Cost
• GLOBAL IMPACTS
• SOCIETAL IMPACTS
• ROLE OF THE CHEMICAL ENGINEER
Geothermal Reservoirs • Heat from the Earth • Clean, renewable resource• Temperatures between ~200˚F and 700˚F• U.S. Commercial power since 1960s. • International market.
http://www.geo-energy.org/reports/Gea-GeothermalBasicsQandA-Sept2012_final.pdf
Geothermal Reservoirs
http://www.geo-energy.org/reports/Gea-GeothermalBasicsQandA-Sept2012_final.pdf
Geothermal Reservoirs • ~4,000 miles deep• ~5,500°C• 42 million megawatts (MW) per year• Geothermal is constantly available
http://www.geo-energy.org/reports/Gea-GeothermalBasicsQandA-Sept2012_final.pdf
Geothermal Energy Production
http://www.geo-energy.org/reports/Gea-GeothermalBasicsQandA-Sept2012_final.pdf
Geothermal Energy Production
http://www.geo-energy.org/reports/Gea-GeothermalBasicsQandA-Sept2012_final.pdf
Geothermal Energy Production
http://www.geo-energy.org/reports/Gea-GeothermalBasicsQandA-Sept2012_final.pdf
Geothermal Energy Production
http://www.geo-energy.org/reports/Gea-GeothermalBasicsQandA-Sept2012_final.pdf
Geothermal Energy Production
http://www.geo-energy.org/reports/Gea-GeothermalBasicsQandA-Sept2012_final.pdf
Geothermal Energy Production
http://srren.ipcc-wg3.de/report/IPCC_SRREN_Ch04.pdf
Geothermal Energy Production• High-pressure geothermal water separates into steam and water• 900 MW of the 3,187 MW of installed geothermal capacity in the U.S
http://www.geo-energy.org/reports/Gea-GeothermalBasicsQandA-Sept2012_final.pdf
Geothermal Energy Cost
http://srren.ipcc-wg3.de/report/IPCC_SRREN_Ch04.pdf
Social Impacts• Plants produce some sludge
• Zinc, sulfur, silica, etc.
• Small visual impact• No storage, transportation, or combustion fuels
• Lower energy cost per kWh• BHP currently $0.0825• Geothermal about $0.05
Sources: http://srren.ipcc-wg3.de/report/IPCC_SRREN_Ch04.pdfhttp://www1.eere.energy.gov/geothermal/faqs.html#geothermal_energy_cost
Social Impacts• 90% availabilities or higher
• Coal only 75%
• May cause sink holes from voids• Wairakei sinks 0.5 meters per year since power station (New
Zealand)
Sources: http://www.teara.govt.nz/en/geothermal-energy/page-5 http://www1.eere.energy.gov/geothermal/faqs.html#geothermal_energy_cost
Global Impacts• Low emissions compared to coal plants
• Can be utilized almost anywhere• Steam reservoirs• Heat pumps• Magma awaiting technology
Sources: http://srren.ipcc-wg3.de/report/IPCC_SRREN_Ch04.pdfhttp://www1.eere.energy.gov/geothermal/faqs.html#geothermal_energy_cost
Global Impacts• Increase rate of natural emissions
• Removes heat from reservoirs 10x replenishment
• Renewable resource• Recycle the material back to energy source
Sources: http://srren.ipcc-wg3.de/report/IPCC_SRREN_Ch04.pdfhttp://www1.eere.energy.gov/geothermal/faqs.html#geothermal_energy_cost
Role of Chemical Engineers• EGS
• CO2ETM
• Small scale heating
• Research and Development
Enhanced Geothermal Systems• Apply small forces to stimulate rock layers to slip
• Different than oil and gas “fracking”
• Hot rock and cool water• Thermal Contraction
• Closed Loop Technology
http://www.geysers.com/systems.aspx
Enhanced Geothermal Systems
• Favorable EGS • Temps at ~2-6 miles below surface
http://www.geysers.com/untapped.aspx
CO2ETM
• GreenFire Energy
• St. John’s Dome formation near Springerville, AZ
• Compress CO2 and pump underground
• Carbon Sequestrationhttp://energy.gov/articles/innovative-geothermal-startup-will-put-carbon-dioxide-good-use
Discussion• Is geothermal energy more economically feasible than
coal powered plants?
• Where can CO2ETM be applied across the US?
• What are some risks associated with geothermal energy?