The Lake Source Cooling (LSC) project began providing 16,000 tons of cooling (1 ton of cooling = 12,000 Btu/hr, or approximately one large residential window air conditioner) to Cornell University's Ithaca campus in July of 2000 with an 86% reduction in energy use versus conventional cooling alternatives. This project has almost completely replaced mechanical refrigeration for the Cornell district cooling system with the following benefits:
Lake Source Cooling Facility
- LSC has replaced over 40,000 pounds of CFC refrigerants which are known to deplete the ozone layer.
- LSC saves approximately 25,000,000 kilowatt-hours of electricity each year. This reduced Cornell's electricity demand by 10%.
- LSC has reduced associated emissions of greenhouse gasses by up to 37 tons/year of SO2, 16 tons/year of NOx, and 11,000 tons/year of CO2.
- LSC is a model for sustainability and has become an invaluable community outreach and educational tool.
- Data collected in association with LSC have been invaluable for regional and local watershed planning efforts.
Chillers, heat exchangers, and chilled water pumps at the Lake Source Cooling facility
LSC draws water through a 2mm wedge-wire screened intake about 10 feet above the lake bottom, at a water depth of 250 feet. At this depth, Cayuga Lake remains cold (about 39°F) year-round. The cold water is piped to a shoreline heat exchange facility, where it transfers its coldness through solid stainless-steel plates to water that circulates to the campus in a second loop of pipeline. The two water flows can never mix. Water drawn from deep in the lake is returned through a diffuser located about 500 feet offshore, at a water depth of 10 ft. The only change in the Cayuga Lake water is addition of heat; all the heat added to the lake is released each winter. The chilled campus water is pumped up to the campus to cool equipment and buildings via a closed-loop system, and because heat flows naturally from hot to cold, no extra energy is required beyond that needed to move the water through the pipes.
The renewable resource tapped by LSC has reduced Cornell's reliance on fossil fuels. Since coming on line, LSC has saved 86,000,000 kilowatt-hours of electricity or an average of 25,000,00 KW per year, enough to continuously supply 2500 homes in Tompkins County. This represents about an 86% reduction in energy use for campus cooling. Energy savings for an average year is depicted by the following chart:
LSC has also reduced the pollutants associated with electricity generation (greenhouse gases, acid rain, and the effects of mining and transporting oil and coal).
For more information, check out the web site in the sidebar above, or email Tim Peer, Energy Plant Manager: tsp1@cornell.edu.
