ENERGY SERVICES ENVIRONMENTAL BENEFITS AND ENERGY SAVINGS

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1 ENERGY SERVICES University of California Los Angeles reduces operating costs and air pollution with landfill gasfueled cogeneration and creative financing. ENVIRONMENTAL BENEFITS AND ENERGY SAVINGS Reduced overall campus emissions by 34% 36 ton reduction in smog-forming pollutants per year Benchmark BACT for NOx in LA Basin decreased 33% from 9ppm to 6ppm 4 million cubic feet of landfill gas converted daily from waste gas to useful, inexpensive fuel Replacement of 1/3 natural gas usage with landfill gas results in $250,000 savings per year Elimination of 20,000 lbs of CFCs Potable water usage reduced 60% by recycling gray water CHP SYSTEM SPECIFICATIONS 234 MMBTUs/hour heating capacity 730 billion BTUs produced annually 43 MW capacity 250 GWh produced annually 85% of demand 16,600 tons cooling capacity 5300 tons cooling reserve Over 13 million square feet served SEARCH WORDS: DISTRICT ENERGY, CHP, COGENERATION, LANDFILL GAS, LFG, BROWNFIELD, GRAY WATER, SUPPLY-SIDE MANAGEMENT INTERNATIONAL DISTRICT ENERGY ASSOCIATION OAK RIDGE NATIONAL LABORATORY UNITED STATES DEPARTMENT OF ENERGY

2 CASE INTRODUCTION T he University of California Los Angeles is located in the Los Angeles basin, long known for both its persistent smog and strong environmental regulations. In recent years, as the University s energy needs grew, it was challenged with aging cooling equipment (with rising failure rates) and decreased funding from the state. UCLA needed to develop new sources of energy, but it wished to do so in an environmentally-friendly manner. The university had already set aggressive goals for itself with respect to minimizing its impact on the environment and was implementing numerous demand-side management initiatives. This project was an opportunity to begin achieving those goals on the supply side. Four objectives were identified: Increasing system reliability Meeting energy needs efficiently Improving the environment Reducing cost The solution employed to meet these objectives involved co-firing the university s cogeneration plant with a blend of natural gas and landfill gas. CHP: CHP SYSTEM METRICS Two 14.5 MW combustion turbine generators fueled by 65% natural gas and 35% landfill gas Two heat recovery steam generators (HRSG) driven by the combustion 660 psig One condensing steam turbine electric generator HEAT CAPACITY: 234 MMBTU S/hour HEAT PRODUCTION: 730 billion BTU s /year ELECTRIC CAPACITY: 43 MW ELECTRIC PRODUCTION: 250 GWh/year COOLING CAPACITY: 16,600 tons with 5,300 tons reserve COOLING PRODUCTION: 870 billion BTUs/yr COOLING ENERGY SOURCE: Two steam turbine-driven centrifugal chillers and one electric-driven chiller Four single stage absorption chillers for additional chilled water production. A SUITABLE SOLUTION THE ANSWER MAY BE NO FURTHER THAN YOUR OWN BACKYARD Figure 1. UCLA s CHP facilities. Source: UCLA. To achieve its efficiency objective, UCLA needed a solution that could squeeze every last bit of energy out of a clean burning fuel source. Cogeneration was the way to go, since the plant could generate both electricity and thermal energy for the same process, resulting in double the efficiency of separate processes. Natural gas was chosen to fuel the plant, which would satisfy 85% of the campus electrical needs. UCLA, however, did not stop there. It asked the question whether or not any alternative fuels may be available, and they found the answer just five miles off campus.

3 The Mountaingate Landfill was a 375-acre waste facility containing 21 million tons of solid waste. It had been closed and converted to a golf course in Gas from the landfill was being flared off to prevent buildup, but the gas was not being used for any power generation-related purpose. Landfill gas is a valuable source of energy, with heat content of approximately 500 BTUs per cubic foot about half of that found in commercially marketed natural gas. UCLA worked out an arrangement with GSF Energy, Inc., operators of the landfill s gas control recovery plant, to purchase purified methane gas and to have it piped 4.5 miles to campus. UCLA then compressed the gas to about 500 psi and blended it with natural gas that the plant otherwise would have burned, saving approximately $250,000 annually. LFG use is not the only form of innovation at UCLA. Conventional cooling towers use up a lot of water during normal operation, and the university decided, instead, to use gray water recovered from the cooling systems of campus buildings. The result is a savings of 70 million gallons of potable water, which otherwise would have been used by the cooling system. Figure 2. The golf course at Mountaingate. Source: Mountaingate/GSF Energy, Inc. FINANCING ISSUES PARTNERS PROVE BETTER THAN INVESTORS There are many good projects which are never implemented because of financing issues. The causes range from outright lack of economic feasibility to unwillingness of investors to shoulder too much risk. From a technical perspective, the UCLA cogeneration project looked like a good one, but fiscal issues could have threatened the project s survival. First, the state government was already becoming conservative in its outlays to the university system. Funding for the University of California system was curtailed severely during the early 90s, when California s defense-based economy started to slow down. UCLA was not likely to squeeze additional funding for the project out of the state legislature. Second, the state s debt rating was a variable dependent upon many other factors. Using state revenue bonds to finance the project would introduce that variability into the cost, potentially turning a feasible project into an unfeasible one. It was decided that the best course of action was to isolate the project s funding from external factors by issuing Certificates of Participation to lenders. The certificates are essentially loan agreements paid back with the operating savings realized by the new system. This approach allowed UCLA to ensure that the cost of borrowed funds accurately reflected the financial soundness of the project. The cogeneration system required an initial investment of $188 million, which will be paid off over 22 years. After that, it will provide savings of over $25 million over its anticipated life span. PARTNERS DESIGN: Parsons Municipal Services, Inc. CONSTRUCTION: Kiewit Pacific LFG SUPPLY: GSF Energy, Inc. Figure 3. The LFG recovery facility at Mountaingate. Source: Mountaingate/GSF Energy, Inc. LOCAL UTILITY: L.A. Dept. of Water and Power

4 PROJECT IMPACT Overall campus emissions have been reduced 34%. Over 20,000 lbs of CFC refrigerants have been eliminated by discontinuing use of 18 building-mounted chillers. LFG replaces 1/3 of UCLA s natural gas usage and eliminates the need for Mountaingate to flare off 4 million cubic feet of LFG per day. The project has saved the L.A. basin from 36 tons of smog-forming pollutants each year. Beyond its environmental contributions, the plant has also benefited the community during times of crisis. During the 1994 Northridge earthquake, thousands of people served by the Los Angeles Department of Water and Power lost service. UCLA s Energy Systems Facility was able to supply 20,000 homes with power during that time. UCLA is now adding chilled water thermal storage capacity, which will allow it to minimize the amount of time the plant must run during peak electric demand hours. UCLA won the International District Energy Association s System of the Year Award in 1997 and regularly hosts representatives from other universities that are interested in developing their own environmentally-friendly power generation solutions. Benchmark BACT for NOx in Los Angeles has been reduced 33% from 9ppm to 6ppm. Water usage has been decreased by 60%, 70 million gallons/year, by utilizing campus gray water. Figure 5. A close-up view of the CHP facilities at UCLA. Source: UCLA. Figure 4. Landfill gas is drawn out of the Mountaingate facility, cleansed of impurities, and then piped 4.5 miles to the UCLA campus, where it is blended with natural gas. The resulting mixture is used to co-fire the UCLA Energy Services Facility. Source: NST/Engineers.

5 CASE STUDY CONTACTS AND SPONSORS FOR MORE INFORMATION, PLEASE CONTACT: David Johnson Director of Energy Services The University of California Los Angeles (310) phone (310) fax Robert Thornton, President International District Energy Association 125 Turnpike Road, Suite 4 Westborough, MA (508) phone (508) fax [email protected] THIS CASE STUDY REPORT MADE POSSIBLE BY: AND INTERNATIONAL DISTRICT ENERGY ASSOCIATION OAK RIDGE NATIONAL LABORATORY UNITED STATES DEPARTMENT OF ENERGY