GLHN Architects & Engineers, Inc. Chilled Water System New Mexico State University Not For Construction 0874.00 Utility Development Plan June 16, 2009 Stage Two Report CHILLED WATER SYSTEM INTRODUCTION New Mexico State University currently uses a chilled water production and distribution system in order to provide space cooling services for 56 buildings on the main campus, comprising nearly 3,800,000 square feet of conditioned space. According to recent history, approximately 18,250,000 ton-hrs of refrigeration is delivered to campus annually at a peak rate of roughly 6,600 tons. CHILLED WATER SYSTEM DESCRIPTION The current chilled water production manifold for the NMSU campus consists of three 1500 ton Carrier 19XR electrically driven centrifugal chillers and two nominal 1570 ton Carrier 16JR-150L double effect absorption chillers. Also included in the production manifold is a thermal storage facility consisting of two 1.5 million gallon tanks underground at the central utility plant capable of storing up to 25,000 ton-hrs of refrigeration. In all, the production manifold is capable of producing up to 6,600 tons of chilled water. Chilled water is delivered to campus through a primary-secondary-tertiary pumping arrangement, representative of dedicated constant speed chiller pumps, independent building booster pumps and the main pumping manifold which moves chilled water from the central utility plant out to the buildings as demanded and back to the central plant. This main secondary pumping manifold consists of four 3300 gpm units capable of producing 210 ft of head for a total delivery capacity to campus of 13,200 gpm. Due to the fact that the thermal storage tank is open to atmosphere and also open to the system without a closed loop separation, the returning pressure of the chilled water must be reduced to a level of about 15 psi. The secondary distributional pumping manifold is thereby arranged in a somewhat unorthodox configuration being able to lower the return chilled water pressure by forcing the flow through charging turbines which are directly connected to the pump and motor assembly in order to supplement the electrical work of the pump motor. Although there are still inherent losses in pressure through this arrangement, given the configuration of the thermal storage facility, this pumping scheme makes the best out of a somewhat unattractive energy drain. Chilled water is delivered to campus via a distribution network consisting of roughly 20,000 linear feet of both supply and return piping routed both in the utility tunnels and underground in a direct bury configuration. Chilled water piping is mostly schedule 40 steel with some lengths of pipe being PVC. Chilled water is delivered to campus at a temperature of 42°F and returns to the central utility plant at a temperature of 54°F for a total campus delta T of 12°F. As it stands, the system does appear to have some trouble delivering the level of demand of chilled water during peak conditions, mostly late in the summer. Because of this fact,
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GLHN Architects & Engineers, Inc. Chilled Water System New Mexico State University Not For Construction 0874.00 Utility Development Plan June 16, 2009 Stage Two Report
CHILLED WATER SYSTEM
INTRODUCTION New Mexico State University currently uses a chilled water production and distribution system in order to provide space cooling services for 56 buildings on the main campus, comprising nearly 3,800,000 square feet of conditioned space. According to recent history, approximately 18,250,000 ton-hrs of refrigeration is delivered to campus annually at a peak rate of roughly 6,600 tons. CHILLED WATER SYSTEM DESCRIPTION The current chilled water production manifold for the NMSU campus consists of three 1500 ton Carrier 19XR electrically driven centrifugal chillers and two nominal 1570 ton Carrier 16JR-150L double effect absorption chillers. Also included in the production manifold is a thermal storage facility consisting of two 1.5 million gallon tanks underground at the central utility plant capable of storing up to 25,000 ton-hrs of refrigeration. In all, the production manifold is capable of producing up to 6,600 tons of chilled water. Chilled water is delivered to campus through a primary-secondary-tertiary pumping arrangement, representative of dedicated constant speed chiller pumps, independent building booster pumps and the main pumping manifold which moves chilled water from the central utility plant out to the buildings as demanded and back to the central plant. This main secondary pumping manifold consists of four 3300 gpm units capable of producing 210 ft of head for a total delivery capacity to campus of 13,200 gpm. Due to the fact that the thermal storage tank is open to atmosphere and also open to the system without a closed loop separation, the returning pressure of the chilled water must be reduced to a level of about 15 psi. The secondary distributional pumping manifold is thereby arranged in a somewhat unorthodox configuration being able to lower the return chilled water pressure by forcing the flow through charging turbines which are directly connected to the pump and motor assembly in order to supplement the electrical work of the pump motor. Although there are still inherent losses in pressure through this arrangement, given the configuration of the thermal storage facility, this pumping scheme makes the best out of a somewhat unattractive energy drain. Chilled water is delivered to campus via a distribution network consisting of roughly 20,000 linear feet of both supply and return piping routed both in the utility tunnels and underground in a direct bury configuration. Chilled water piping is mostly schedule 40 steel with some lengths of pipe being PVC. Chilled water is delivered to campus at a temperature of 42°F and returns to the central utility plant at a temperature of 54°F for a total campus delta T of 12°F. As it stands, the system does appear to have some trouble delivering the level of demand of chilled water during peak conditions, mostly late in the summer. Because of this fact,
GLHN Architects & Engineers, Inc. Chilled Water System New Mexico State University Not For Construction 0874.00 Utility Development Plan June 16, 2009 Stage Two Report
the system should not be considered adequate for the current needs of the campus and further review is necessary to consider opportunities to alleviate this issue. CHILLED WATER LOADS As stated above, recent annual records indicate an operational peak chilled water delivery capacity of 6,600 tons for an annual consumption of roughly 18,250,000 ton-hrs annually. Due to the lack of and format of recorded data available, these figures, along with the U.S. Department of Energy open source building energy modeling software known as eQUEST, have been used to generate an hourly annual profile of chilled water usage on campus in order to attain the highest resolution of data available for evaluation. Figure 1 below represents the monthly consumption of chilled water by the NMSU main campus, representative of the year 2008.
Figure 1 – 2008 Monthly Chilled Water Usage
As seen in Figure 1, usage peaks in the summer months and dies down to a minimum for building core cooling in the winter, as would be expected, ranging from 800,000 ton-hrs a month in the winter to 2,750,000 ton-hrs a month in the summer. Utilizing the hourly annual chilled water profile developed in eQUEST, a chilled water load envelope for the year has been developed. Average days for each month are generated on an hourly scale in order to obtain a brief comprehensive view of the hourly,
GLHN Architects & Engineers, Inc. Chilled Water System New Mexico State University Not For Construction 0874.00 Utility Development Plan June 16, 2009 Stage Two Report
monthly and annual behavior of the system. Figure 2 below represents what the annual chilled water load envelope was for the campus in 2008.
Figure 2 – 2008 NMSU Chilled Water Load Envelope
As seen in Figure 2, levels peak midday in the summer months and bottom out during the winter nights, as would be expected. The area under this curve is representative of the totalized annual chilled water usage by the main campus. This is a somewhat typical load envelope for chilled water usage at any level and is representative of what is happening on an hourly level for each month of the year. FLOW ANALYSIS According to the Physical Plant Department, the chillers are maxed out on capacity during peak flow conditions. The individual building loads were reverse calculated knowing the capacity of the chiller manifold and using adjusted standard cooling load densities relative to each building type. The combination of this data set along with the known averaged campus delta T of 12°F allows procuring of the flow information to effectively evaluate system as it currently exists.
GLHN Architects & Engineers, Inc. Chilled Water System New Mexico State University Not For Construction 0874.00 Utility Development Plan June 16, 2009 Stage Two Report
In order to best procure a comprehensive flow model of the NMSU chilled water distribution system, a software package known as Pipe-FLO has been utilized to simulate existing campus peak flow conditions. It should be noted that this model is a best representation of the campus chilled water system and should not be considered an absolute representation. In order to fill in gaps between available data sets, assumptions have been made to determine individual building cooling densities according to function. It should also be noted that for the purposes of evaluating the distribution system, the pumping arrangement of the model does not include individual building pumps, and it is assumed that, in general, these tertiary pumps pick up nearly all of the head loss through individual building piping systems and are sized to do just that. It should also be understood that as individual building improvements are made in the near future, the delta T for each building may increase or decrease depending on the specific cooling issues relative to that building, whether it is a three way valve system with constant speed pumping and mixing or a situation in which pipes are clogged and restricting proper flow through heat transfer coils. It is for this reason, in addition to the knowledge that projects are currently in planning and operation to optimize the heat transfer systems in delinquent buildings, that in analyzing flow in consideration for expansion, or rather a future state of the system, all building temperature differentials are brought to an average number of 12°F for the purposes of this study. Before examination of the flow model, there are a few configurations that should be noted. There is a separate 14” line leaving the east side of the plant that serves the new science hall and the Zuhl Library with a connection to the main distribution network at the Branson Hall Library and Hershel Zohn Theatre area. This connection is shown as normally closed in this model, corresponding to operator observation at the Physical Plant Department. There is another connection shown as normally closed between Breland Hall and Milton Hall, also according to operator observation. It should also be observed that the existing tunnel connection at the Chamisa Village is unorthodox in that it pulls supply water from the tunnel return line and returns it to the same line. This ultimately means that there is no supply demand for the Chamisa Village in terms of flow. It is assumed this sort of connection was implemented with oversized fan coils and sub-par cooling capacity and ventilation in order to make an addition to a system believed to already be at capacity. Head loss through the existing system is calculated in the existing flow model and shown to be estimated at 136’ for a delivery of 13,093.5 gpm. This is an estimated figure and does not take into account the open atmosphere thermal storage facility or building tertiary pumps. It is, however, a relatively accurate estimation of the energy lost in delivering and returning chilled water up to the building level. In order to plan for expansion it is crucial to understand distributional pipe capacity, which can be indicated in a comprehensive flow model by showing flow velocities. It is apparent in looking at this velocity gradient that there are very high velocities in and around the central plant area, indicating that the roots of the distribution network have become too small to sufficiently support flow to the extents of the system. It can also be seen that the system is approaching unacceptable velocities just to the north of the plant
GLHN Architects & Engineers, Inc. Chilled Water System New Mexico State University Not For Construction 0874.00 Utility Development Plan June 16, 2009 Stage Two Report
and extending east though the Pan Am Tunnel. It is also evident that velocities are approaching unacceptable levels in the Sweet Tunnel due south from the plant. The most noticeable high flow velocity is within the central plant itself, forcing 13,000 gpm through a 20” main distribution header during times of peak flow for a velocity of over 15 ft/s. With high velocities branching off in every direction from the area of chilled water production, there is the indication that additional loads to the system at any location could push the central plant beyond its capacity for flow distribution not only in terms of pumping capacity, but in relation to flow capacity in the existing pipeline network. In calculating existing peak flow values, it was discovered that the central plant’s capacity for chilled water production and distribution did not match the recommended cooling densities in this climatic zone for the buildings on the system. It is currently estimated the central utility plant is capable of providing only 2/3 of the ideal refrigeration to campus during times of peak conditions. Discussions with NMSU facilities staff indicate that during peak conditions, the central plant does in fact have problems with successful delivery of chilled water to every building on campus. During peak flow the central plant and facilities personnel have devised ways of rerouting flow from the plant and around campus by changing valve positions, sometimes hourly, according to what buildings have reported unacceptable service. It is also believed that in order to best condition buildings on campus with consideration to the low chilled water production capacity, many of the campus buildings are receiving less than adequate ventilation air in order to significantly cut down on load. Aside from the issues of chilled water production, distribution capacity has been found to be limited on a similar scale. As the distribution pumping scheme exists, there is no defined distribution header where flow can gather before it is separated off appropriately in different directions to campus. Rather, the distribution pumps are scattered throughout the plant and route all flow to the east side of the building for campus distribution. There does exist a length of pipe routing some pressurized flow from the east to the west side of the plant in order to serve buildings to the north and west of the plant, however, in the flow model this line becomes restricted in capacity during peak flow periods, making for significant head loss in the system and reducing the plant’s capacity to deliver chilled water to this set of buildings. At times this issue becomes so intense that one chiller is routed away from the secondary distribution pumps and delivers as best it can to the distribution system with only pressurization from its dedicated primary pump, according to central plant staff. Outside of the plant there are significant restrictions to flow delivery in all directions in the distribution system with the heaviest restrictions to the north and northeast areas of campus. In addition to the questionable physical nature of the distribution pumping system, sheer pumping capacity alone seems to fall short of the ideal. There have been reports by central plant staff that often during the hotter months of the year, isolation valves in the plant and around the distribution area are constantly being manipulated in order to maintain adequate delivery pressure to buildings at the extents of the system. This is an indication of an undersized pumping array and is just as important to consider as chilled water production when making additions to the campus. There is currently no redundancy
GLHN Architects & Engineers, Inc. Chilled Water System New Mexico State University Not For Construction 0874.00 Utility Development Plan June 16, 2009 Stage Two Report
in either chilled water production or distribution capacities, leaving no contingency for equipment failure or opportunities for expanding the system. CHILLED WATER SYSTEM STRATEGIES FOR CAMPUS EXPANSION New Mexico State University has developed an architectural master plan to aid in facilitating structured campus growth in five year phases out through the year 2034. A chilled water system development plan is a crucial counterpart of this equation. Not only are there significant deficiencies with the existing system, but it will need to change in configuration as well to match the progressing architectural build out of the main campus. As noted above, the current chilled water system is vastly undersized for the area of service which means that not only will the system need to expand for the growth of the campus, it will need to immediately expand to begin to appropriately satisfy the chilled water demand for space cooling. Likewise, immediate expansion is a necessity before consideration of adding any building to the load. SYSTEM EXPANSION FOR GROWTH OF CAMPUS Following are brief descriptions of changes to the chilled system through the set phases of campus development. Cost estimates are also provided with inflation factored in. Cost estimates for distributional piping are not included here and can be referenced in the Utility Tunnel System report. For phased distributional piping improvements, see the phased set of utility layout drawings in the back of this section. Phase 1 – 2014 Accounting for not only the current deficiency in production capacity but also the growth of the campus in the first phase, the chilled water peak load increases from 6,600 tons to about 12,500 tons. This is an extreme increase in the system and according to the net present value analyses described below, warrants the addition of a secondary utility plant to connect to the main system. This utility plant can be built having the capability for modular expansion. In other words, not only can chillers be installed only as they become necessary, but the plant can be continuously built up from its base building in a modular fashion as the additional chillers are required. This option reduces the first cost of building the facility greatly as it only needs to be built up to hold the present capacity of equipment. Also as discussed below in the net present value analysis is the attractiveness of adding an ice storage facility to the secondary utility plant. This item is therefore included in the costs for the first phase of development. The last major item included in the first phase is the re-piping and re-sizing of the existing plant chilled water headers. The headers are undersized to a point of constricting flow to campus, increasing the cost of moving chilled water and need to be reconfigured in such a manner so that manual intervention by means of valve repositioning is not required in order to provide appropriate flow to all corners of the campus. In summation, the suggested additions include two 1030 ton double effect absorbers and peripherals, two 2000 ton electric chillers and peripherals, one 1000 ton glycol chiller and peripherals, 43 ice storage tanks, the base building for a secondary utility plant, and the re-piping of the existing plant
GLHN Architects & Engineers, Inc. Chilled Water System New Mexico State University Not For Construction 0874.00 Utility Development Plan June 16, 2009 Stage Two Report
chilled water headers. The combination of these items will be able to meet the foreseen campus peak load while boasting an n+1 redundancy in production and results in a first phase cost of roughly $18,350,000. Additionally, the Arts Complex Ph I, the Bookstore, and Chamisa Ph II are all buildings planned for construction within the next two years. This will possibly not be enough time to expand the current chilled water system to match growth and will need contingency plans to address their chilled water needs. It is recommended that the buildings be outfitted with chilled water distribution systems and temporarily connected to outdoor pad-mounted air cooled reciprocating chillers as standalone systems until the chilled water distribution system is prepared to take on additional load. At this time the main building connections can be disconnected from the air cooled chillers and connected up to the campus chilled water system. The air cooled chillers can then be stored to be used in the future for similar incidents. Cost estimates for outfitting these systems for each of these buildings are included in this report. Phase 2 – 2019 The second phase of development encompasses further growth of the chilled water system and creates an additional peak load of over 2,500 tons. Additions to the system production capacity include one 2000 ton electric chiller and peripherals and results in a second phase cost of roughly $4,519,697. Phase 3 – 2024 This phase of growth harvests an additional peak load of over 3,000 tons and warrants the addition of two 2000 ton electric chillers with peripherals. Estimates for this phase come out to roughly $10,479,000. Phase 4 – 2029 Phase 4 continues the addition of buildings warranting chilled water service and creates an additional peak load of nearly 4,000 tons. The addition of four 2000 ton electric chillers and peripherals will be necessary for this phase and results in costs totaling roughly $17,223,000. Phase 5 – 2034 The final phase of development creates an additional peak chilled water load of nearly 5,500 tons and is mostly on the southern tip of the built out distribution system. At this point in time, should the campus grow according to plan, it may be feasible to create a tertiary chilled water facility in this vicinity and connect it to the main system. Either way, it will be necessary to replace some of the equipment installed in the first phase, as their useful lives will have run their course, and install some new equipment to keep up with the additive loads. In all, this phase will add two 1030 ton absorbers, five 2000 ton electric chillers, one 1000 ton glycol chiller and all the peripherals to match. In all, estimates for this phase come to roughly $36,563,000.
GLHN Architects & Engineers, Inc. Chilled Water System New Mexico State University Not For Construction 0874.00 Utility Development Plan June 16, 2009 Stage Two Report
NET PRESENT VALUE ANALYSIS As mentioned in the Cogeneration System section of this report, the cogeneration model has been outfitted to analyze multiple optional equipment configurations, including the options for ice storage and the comparison between adding two absorbers to the HRSG steam output versus one absorber and one steam driven turbine. Most importantly, the cogeneration model has been outfitted with the capability of projecting system dynamics with respect to the phased build out of the campus. In other words, estimates for the cost of energy consumption in the forms of natural gas and electricity have been generated and used in conjunction with estimates for capital investments in equipment to produce estimates for net present values of the entire 25 year investment as well as leveled annual costs should this be looked at from a “borrowing” perspective. For each run of the net present value analysis, equipment additions have been tailor made to suit each individual scenario. There are a total of 8 scenarios, creating every permutation of the 3 general options. Secondary Utility Plant The first option is to either begin construction of a new utility plant or to tear down and rebuild part of the existing plant. Even if the existing plant were rebuilt there would still be a need for a secondary utility plant, but construction of the new plant could be delayed until about 2019. Plausible locations for the secondary plant include the parking lot immediately east of the Health and Social Services Building, the parking lot just south of the Corbett Center, and the northwest corner of the intramural fields just south of the Activity Center. Since there is an immediate need for improved flow to the northern section of campus and since many of the parking lots around the Corbett Center are already scheduled for demolition, the parking lot immediately east of Health and Social Services and west of the proposed Jordan Parking Garage became a prime candidate. In general, the net present value analysis yielded higher overall costs if the existing plant is rebuilt versus constructing a new facility immediately. Not only does cost analysis indicate near term construction of a secondary facility to be most feasible, but there are many complications to rebuilding an existing facility, especially considering that total shutdown of any branch of equipment is unacceptable, as the campus is constantly requiring these utilities. A preliminary drawing set of a conceptual secondary utility plant are included in this report. Ice Storage System An ice storage option for the chilled water system can be an extremely attractive investment, especially working in conjunction with a demand based electrical rate. Ice storage allows for a dedicated glycol chiller to operate at night during off-peak hours to create chilled water potential via the creation of ice. During the daytime, the glycol loop, connected to the main chilled water system by means of a heat exchanger, is able to extract heat from the chilled water system and use it to melt the ice in the storage tanks, creating “free cooling” during times of more expensive consumption and cutting the
GLHN Architects & Engineers, Inc. Chilled Water System New Mexico State University Not For Construction 0874.00 Utility Development Plan June 16, 2009 Stage Two Report
electrical demand charges by reducing the amount of energy consumption during peak energy hours. A preliminary system is sized to meet the needs of the first phase of growth and includes one 1000 ton glycol chiller working in conjunction with 43 ice storage tanks for a total possible discharge of 5000 tons and a total daily storage capacity of about 14,000 ton-hours. Should this option be considered, further optimization of the system size should be performed in order to maximize savings. In the 8 alternate net present value runs, the ice storage option consistently yielded lower overall expenditures versus excluding it from the chilled water system expansion. In addition to the obvious setbacks of attempting a rebuild of the existing utility plant, there would not be the appropriate spatial requirements to add ice storage to the existing plant and the campus would not be able to reap the benefits of such a facility until construction of the secondary utility plant. Dual Double Effect Absorbers vs. Single Effect Absorber w/ Steam Turbine The heat recovery steam generator outputs a peak load of roughly 22,000 lbs/hr of 100 psi steam. Currently this steam can be sent to campus for space heating in winter months or routed to one of two absorption chillers to create chilled water in summer months. The existing absorbers are significantly de-rated and are in constant need of maintenance. Since these machines are candidates for replacement, the question remains as to what will be most effective replacement in terms of energy usage and economy. Two options have been considered an analyzed. One is to replace them in kind with two new and efficient absorption chillers. The alternate option is to stage a steam turbine and a single stage absorber in series. In this configuration, during the summer months, the steam turbine would take in steam at 100 psi and generate 275 kW of electricity while outputting 15 psi steam to the single effect absorber for the production of chilled water. Either of these two options will effect in a reduction of on-peak electrical consumption and will help to lower overall demand charges by reducing consumption during peaking hours of the day. According to the net present value analysis, each isolated comparison of these two options came out significantly close to one another. Were they to be completely even, it may be beneficial to lean towards the two absorbers versus the absorber and steam turbine due to the increased complexity of the latter system. Overall, the comparison between all 8 scenarios yields 2 closely matched candidates. The least costly scenario was the result from scenario number 3 and consisted of immediate construction of a new utility plant, the inclusion of an ice storage facility, and the addition of two new double effect absorption chillers. This scenario ran a 25 year net present value of roughly $205,123,000 with a leveled annual cost of $11,441,000 and an annual savings from the worst case scenario of $933,000. The close second was scenario number 4, differing from 3 only by the inclusion of a single effect absorber and steam turbine rather than two double effect absorbers. This scenario came in with a 25 year net present value of roughly $206,577,000 with a leveled annual cost of $11,522,000 and an annual savings of $852,000. The next best scenario resulted in a net present value of $214,784,000. The worst case was scenario number 6, consisting of renovation of the existing plant, no ice storage, and the use of a single effect absorber in conjunction with a steam driven turbine. This scenario resulted in a 25 year net present value of $221,844,000 with a leveled annual cost of $12,374,000.
GLHN Architects & Engineers, Inc. Chilled Water System New Mexico State University Not For Construction 0874.00 Utility Development Plan June 16, 2009 Stage Two Report
STAGE 1 PRODUCTION DEFICIENCIES Deficiencies on the production side of the chilled water system have been addressed along with expansion of the system for the growth of the campus. STAGE 1 DISTRIBUTION DEFICIENCIES Undersized Pipe Sizes in and Around the Central Utility Plant During an in depth flow analysis it became evident that the chilled water line sizes in and around the central plant area are nearly too small for acceptable flow velocities and that the main distribution header is significantly smaller than ideal, forcing a peak flow of over 15 ft/s. Were the pumping manifold sufficient to successfully deliver flow during peak demand, this would only be an indication of unnecessary energy loss through friction in the pipe, but in consideration of campus and chilled water distribution expansion, the current pipe sizes and configurations in and around the central plant could pose some serious problems in successfully delivering service to all areas of campus. The re-piping of the chilled water plant header has been addressed in expansion for growth and the line sizes around the area of the existing utility plant will grow in capacity once a secondary plant is installed, alleviating the need for the current plant to push chilled water out to every extent of campus. Distribution Pumping Arrangement Another deficiency noted here, common to many existing chilled water systems, is the overall primary-secondary-tertiary pumping arrangement on campus. Were the system constructed brand new today, it would be recommended to use what is known as a direct primary scheme in which there would be only one set of pumps able to output variable flow to campus and sized to take on the entire head loss from the chiller array to the top of the tallest and farthest building and back. The existing arrangement is a cause for some significant energy loss through constant pumping and 3-way valve arrangements, moving an unnecessary amount of flow. The University is currently investing in a program to retrofit existing buildings with a 2-way valve arrangement, alleviating the need for tertiary pumps. This action will ultimately result in significant energy savings in system pumping. Cool Pool Pumping Arrangement Another notable deficiency that had been addressed in a previous study by GLHN is the fact that the thermal energy storage facility is not only open to atmosphere but open to the campus distribution system as well. This means that in order to keep the “cool pool” from overflowing, system pressure has to be killed off in the return chilled water supply. This in turn means that to successfully pump flow back out to campus, the secondary pumping manifold has to take the flow from almost atmospheric pressure back up to 60 or 70 psi, resulting in significant excess energy costs. It should also be noted that the depth of the cool pool is quite shallow and does not allow for appropriate stratification of the varying temperatures between the top and bottom levels. It is recommended that previously submitted materials by GLHN be reviewed and considered in order to generate additional distributional pumping savings
GLHN Architects & Engineers, Inc. Chilled Water System New Mexico State University Not For Construction 0874.00 Utility Development Plan June 16, 2009 Stage Two Report
Campus Delta T The current 12°F delta T across campus is an acceptable temperature gradient. However, it is not infeasible to obtain a delta T on the order of 16°F for a campus such as this by means of eliminating 3-way valves and constant speed pumps. This issue is addressed above in the distributional pumping arrangement. Absorption Chillers This deficiency is addressed in the planning for campus growth and includes replacement of the existing machines. EMCS It has been observed that the existing data monitoring system for the chilled water system is grossly undersized and fails to capture a comprehensive view of the operation of the distribution system. Not only does the existing system have holes in data capture, processing and storing, there are many buildings that have incomplete monitoring capabilities as currently configured. This deficiency has already been picked up by the University and is currently being improved upon by a dedicated team of personnel.
GLHN Architects & Engineers, Inc. Chilled Water System New Mexico State University Not For Construction 0874.00 Utility Development Plan June 16, 2009 Stage Two Report
GLHN Architects & Engineers, Inc. Chilled Water System New Mexico State University Not For Construction 0874.00 Utility Development Plan June 16, 2009 Stage Two Report
CHWP-3 Cornell 3300 210 - - 200 3 460 1785 VFD
CHWP-4 Cornell 3300 210 - - 200 3 460 1785 VFD
Totals 13200
Charg-1 Cornell 4000 80 - - 125 3 460 1800 VFD
Charg-2 Cornell 4000 80 - - 125 3 460 1800 VFD
Totals 8000
- -
CHP-1 Aurora 3100 95 - - 100 3 460 1750 Constant
CHP-2 Aurora 3100 95 - - 100 3 460 1750 Constant
CHP-3 Aurora 3100 95 - - 100 3 460 1750 Constant
Totals 9300
CHP-4 Aurora 3600 150 - - 200 3 460 1750 Constant
CHP-5 Aurora 3600 150 - - 200 3 460 1750 Constant
Totals 7200
CWP-1 Aurora 5100 65 - - 100 3 460 1188 Constant
CWP-2 Aurora 5100 65 - - 100 3 460 1188 Constant
CWP-3 Aurora 5100 65 - - 100 3 460 1188 Constant
CWP-4 Aurora 6750 95 - - 200 3 460 1188 Constant
CWP-5 Aurora 6750 95 - - 200 3 460 1150 Constant
Totals 28800
Official_Building_Master_List
Current Future
New Mexico State University Lab (SF/Ton) 507 300
Utility Development Plan Acad (SF/Ton) 592 350
2009 Housing (SF/Ton) 761 450
Chilled Water Distribution System Admin (SF/Ton) 592 350
284 Pan American Center 1968 1810 E. University Ave. AUX 215,633 365 729 215,633 616 1,232 215,633 616 1,232 215,633 616 1,232 215,633 616 1,232 215,633 616 1,232 4
604 Pinon Hall 2006 1760 E. University HOUSING 97,395 128 256 97,395 216 433 97,395 216 433 97,395 216 433 97,395 216 433 97,395 216 433 3
263 PSL, Clinton P. Anderson Hall 1965 1050 Stewart St. ACAD - LAB 135,847 268 536 135,847 453 906 135,847 453 906 135,847 453 906 135,847 453 906 135,847 453 906 6
1 SF based on building footprint for three stories
2 following demolition of Chi Omega sorority houses (268)
3 following demolition of Breland Hall Addition (north part of 184)
4 following demolition of Bull Barn (193), Heardsmen Residence (199), Stucky Hall (282), Animal Husbandry (290), and the Feeding Research Building (303)
5 following demolition of PSL West Shop (280), Guardhouse (281), Machine Shop (216), Rocket Shop (243) and East Shop (279)6
following demolition of East and West Greek Complexes (271, 272, 273, 274, 414), Wells Hall (355), Cosmic Ray Lab (398), Theatre Scene Shop (385), Housing Warehouse (467), Ag Service Storage (316) and Flammable Storage (320), SF based on building footprint for two stories
following demolition of Animal Science (376, 241, 198), Tejada Extension Annex (245), Animal Husbandry Barn (162), Sheep Barns (194), Cattle Feed Barn (240), Small Animal Lab (246), Livestock Judging Pavillion (195) and Neale Hall (164)