Toronto company using lake water to cool buildings expands system

A Toronto-based energy company says it is expanding its system that uses cold water from the depths of Lake Ontario to cool several buildings downtown.

Enwave Energy Corporation announced the newest expansion of its deep lake water cooling system at a news conference on Thursday. The system has been in place for 20 years and expansion began in 2021, the company says.

The expansion involves putting a three-kilometre pipe into Lake Ontario, then drawing in water at temperatures of 4 C through a new tunnel about 90 metres below the surface to the company's John Street Energy Centre, near Rees Street and Lake Shore Boulevard W.

Currently, there are three intake pipes that go deep into the bottom of Lake Ontario. The pipe is the fourth one to be put into the lake by the company. The project is expected to be completed and in service this summer.

The system already services more than 100 buildings downtown, including the Toronto Dominion Centre, Fairmont Royal York hotel and The Well, as well as hospitals, residential buildings, data centres and entertainment venues.

Enwave says the expansion will allow it to provide clean energy services to an additional 40 buildings downtown. The cooling provided by the expansion is equivalent to reducing peak electricity demand on Ontario's electricity system by 16 megawatts, the company says.

Carlyle Coutinho, CEO of Enwave Energy Corporation, said the expansion represents years of work, uses Toronto Water's utility system and is the result of a partnership between the company and city. 

"This project is ambitious and it's impactful," Coutinho told reporters.

"Deep lake water cooling is a clean technology that enables tremendous benefit to all stakeholders, including our customers, the city and the province, by displacing and saving significant amounts of electricity and water."

Coutinho said lake water is pumped through the deep lake water cooling system through kilometres of pipe underground.

"Instead of heat being pushed out into the atmosphere from buildings, they deposit it into our water and we keep on recycling it through an energy recycling system," he said. 

With the expansion, the company estimates the system will save 832 million litres of water annually — equivalent to nearly 350 Olympic-size swimming pools.

As for the environmental impact of the fourth pipe, Coutinho said in an interview that the project has passed through all environmental assessments. 

"We've worked with all the local different special interest groups. We didn't have one comment. Everybody's been on side. The water out there is very cold. And we've worked with all the local fisheries and everybody else," he said.