Stockholm, Sweden 
Sweden is a world leader in SWAC development.  There are currently more than 80,000 tons of deep lake/SWAC in Stockholm, Sweden.  Several other Swedish cities, including Jonkoping, Upplands Vasby, Solna, Sollentuna and Sodertalje, have SWAC systems with up to 15,000 tons of capacity.

Anders Rydaker and Ingvar Larsson, two members of the Market Street Energy Company management team, were actively involved in the development of these systems in Sweden.  In 2003, Rydaker received Sweden’s Prestigious Energy Prize for pioneering the development of numerous district cooling systems in the country.

Toronto, Canada
The Toronto Deep Lake system was developed in conjunction with the City of Toronto’s fresh water acquisition development.  It is the largest renewable lake source system in connection with a municipal dual drinking water and cool energy service.

The Toronto project utilizes a three-intake pipe system with an intake at a depth of 270 feet.  The lake water distribution piping system brings the cold water to a pumping station.  Heat exchangers are used to extract the coldness from the drinking water to a closed-loop distribution system that is connected to individual buildings for air conditioning purposes.  The heat exchanger separates the district cooling closed-loop system water from the cold drinking water that is distributed throughout the City of Toronto.

Ithaca, New York
Cornell University is consuming much less energy and helping regional electric power plants release fewer pollutants into the air thanks to the university’s innovative Lake Source Cooling project, which uses naturally cold, deep water from Cayuga Lake to cool campus buildings.

Although the concept is not new, this is the first such installation by a university anywhere in the world and the first to be installed in a small freshwater lake.  The Lake Source Cooling project began providing 16,000 tons of cooling to Cornell University’s Ithaca campus in July 2000, resulting in an 86 percent reduction in energy use for campus cooling. 

The system draws 39˚F water from a water depth of 250 feet.  The cold water is piped to a shoreline heat exchange facility, where it transfers its coldness to water that circulates to the campus in a second loop of pipeline.  Water drawn from deep in the lake is returned at a water depth of 10 feet.  The only change in the Cayuga Lake water is the addition of heat, all of which is released each winter.

For more information, visit www.sustainablecampus.cornell.edu/energy-lake.htm.