Toronto Air Conditioning To Be Powered By Lake Water

By MARTIN MITTELSTAEDT
Globe and Mail
Thursday, June 20, 2002 – Page A18

Water from the frigid depths of Lake Ontario will soon be cooling many of Toronto's downtown buildings, following the groundbreaking yesterday of a novel $180-million project to use the lake as a giant air conditioning system for the city.

The deep lake cooling project, as it has been dubbed, is one of the first commercial efforts in the world to draw on the enormous reservoir of cold naturally available in lake water to replace conventional air conditioning.

The cooling system is expected to be operating by the summer of 2004, and has already been chosen to supply air conditioning in such showcase buildings as the Air Canada Centre and the Metro Toronto Convention Centre. The number of buildings on the system could eventually swell to about 100.

Enwave District Energy Ltd., the project owner, calculates that the air pollution reduction from the system will be the equivalent of taking 5,000 to 8,000 cars off the road.

The project was lauded yesterday by conservationists, including Robert F. Kennedy Jr., a well-known environmentalist and scion of the famous U.S. political family.

"This technology . . . is going to be an example to the rest of the world of what we can do if governments want to be far-sighted, if industry wants to be far-sighted and visionary," Mr. Kennedy said.

The deep lake cooling proposal has been around since the mid-1980s, when city officials and energy experts first began to ponder if it made economic sense to use cold water from Lake Ontario for air conditioning. Lake Ontario is the smallest of the Great Lakes, but it is deep and cold.

The key to the project is a plastic pipe more than 1.5 metres in diameter that will extend like a giant straw 4.7 kilometres into Lake Ontario, south of the Toronto Islands, where it will be used to suck icy water from a depth of 85 metres. After it is cleaned, the cold lake water passes through a heat exchanger -- a system of big metal sleeves -- where it will draw the heat from a separate stream of water used for the air conditioning in buildings.