Deep Lake Water Cooling and the City
Thought Toronto was already cool? Well, we're even cooler these days because of an innovative project that reduces our energy use.
Enwave Energy Corporation, through partial financial backing from the City of Toronto as one of the two shareholders of Enwave, developed the Deep Lake Water Cooling system that uses the cool energy in cold water to air-condition high-rise buildings in downtown Toronto. The system benefits the City by:
- reducing energy consumption by up to 90 per cent (compared to conventional chillers)
- reducing carbon dioxide emissions
- improving the water supply by using new intake pipes that are deeper
- investing in a corporation in which the City is a shareholder
How the system works
Enwave's three intake pipes draw water (4 degrees Celsius) from 5 kilometres off the shore of Lake Ontario at a depth of 83 metres below the surface. Naturally cold water makes its way to the City's John Street Pumping Station. There, heat exchangers facilitate the energy transfer between the icy cold lake water and the Enwave closed chilled water supply loop.
The water drawn from the lake continues on its regular route through the John Street Pumping Station for normal distribution into the City water supply. Enwave uses only the coldness from the lake water, not the actual water, to provide the alternative to conventional air-conditioning.
The City of Toronto taps into the system
Metro Hall, a 27 storey office building in Toronto, went online with Enwave's Deep Lake Water Cooling system in June 2006. Energy consumption at Metro Hall will be reduced by 3 million kilowatt-hours per year and reduce CO2 emissions by 732 tonnes annually - equivalent to taking 160 cars off the road. Metro Hall's savings are detailed below:
Metro Hall's energy savings
||3,000,000 kilowatt-hours per year less
|Power saved is sufficient to supply
|Reduction in Water Consumption from Cooling Towers
||4,400 cubic metres per year less
|Greenhouse Gas Reduction: Carbon Dioxide
||732 tonnes per year
|Number of Cars with equivalent emissions
In June 2006, City Council approved a staff report (pdf 8 pages, 38 KB) that recommended proceeding with planning to get Old City Hall online with the system; this will happen by the end of 2010. In July 2007, City Council gave the go ahead to put New City Hall on the system; this is planned for 2008.
Old City Hall, currently cooled using window air conditioning units, would be the first historical facility to be added to the DLWC system. Learn more about the benefits of adding Old City Hall to Enwave's Deep Lake Water Cooling system.