Toronto Hydro begins supplying district heating from its newly-constructed steam plant at Pearl Street.


Provincial Air Pollution Control Service approves a small expansion to Pearl Street Steam Plant and city council authorizes the construction of a new steam plant from a consortium of hospitals at Walton Street.


City council commissions a study to chart the potential expansion of district heating in downtown Toronto.


Commissioning of Walton Street Steam Plant.


Recommendations of District Heating Study adopted by council:

  • Integration of the six steam distribution networks operating in Toronto to be managed by a new corporation.
  • Construction of a combined refuse-fired and fossil-fuel fired steam plant outside of downtown to provide base load for integrated system.
  • Decommissioning of Pearl Street Steam Plant.


Five district energy systems operating in Toronto – UofT, Hospitals Steam Corporation, Toronto Hydro, Queen's Park (ORC) and the Toronto Terminal Railways Corporation – agree to integrate their respective systems into one entity that will serve the heating needs of downtown Toronto. The new district heating network will ultimately be supplied with steam from a refuse fired steam plant which will incinerate Toronto's garbage and produce both power and heat from the refuse – a vision promoted by Works Commissioner, Ray Bremner.


TTR pulls out of developing consortium.


City council authorizes $2.7 million purchase of Gulf Oil site at Cherry Street and Lakeshore Boulevard as the site for the proposed refuse-fired steam plant.


Provincial Government approves of consortium's plan for an integrated steam network. The Toronto District Heating Corporation Act, 1980 receives third reading in legislature.


Metro council approves Waste Management Master Plan which includes City of Toronto proposal for a refuse-fired steam plant, however, Keele Valley Landfill site is purchased and Metro decides to divert waste to landfill rather than incinerate at Portlands.


Canada Mortgage and Housing Corporation presents results of a study of "Free cool" described as "the concept of pumping water from the bed of Lake Ontario through a hydraulic heat transfer system to cool major downtown buildings." Study suggests that it is "technically and financially feasible" to displace 137,000 THR of electrically-generated cooling capacity in downtown Toronto. Estimated cost of project $680 million.


The Toronto District Heating Corporation (TDHC) Act, 1982 is proclaimed by the Ontario Legislature. The non-share capital corporation or non-profit entity, which will operate the new district energy system for the benefit of the founding partners, is thus created. The steam networks of the University Avenue hospitals, Toronto Hydro, and Queen's Park are amalgamated. UofT declines to cede its system to the new company but, nevertheless, takes two seats on the Board of Directors. Toronto Hydro takes an additional two years (1984) to finalize the transfer of its assets to the TDHC.

The TDHC legislation is very prohibitive in order to mitigate financial risk for the founding non-profit entities. However, risk mitigation comes at a high business cost. The TDHC legislation restricts long term borrowing and requires the company to seek approval from the City for many business transactions. It severely inhibits the company's growth resulting in many missed business opportunities. Plans for a refuse-fired steam plant are abandoned.


Queen's Park plant decommissioned and TTR plant demolished with customers from the latter system being transferred to TDHC.


TDHC begins supplying steam for absorption cooling. Queen's Park Plant is re-commissioned, adding 15% capacity to system.


TDHC installs a new low Nox boiler at the Walton Street Plant adding 18% more capacity to the steam system.


TDHC opens Chilled Water Plant in the south building of the Metro Toronto Convention Centre. Unique design locates the wet well of the Chilled Water Plant in the centre of the parking ramp making use of otherwise wasted space. Because of the restrictive TDHC legislation, the company is forced to sell receivables to finance the construction of the plant.


New TDHC Chairman, Dennis Fotinos, secures the financial backing of Borealis (a wholly owned subsidiary of OMERS) and begins the process to reconstitute the TDHC as a private, for-profit company in order to pursue expansion.

Environmental Assessment for the Deep Lake Water Cooling project receives approval.


International District Energy Association (IDEA) recognizes TDHC as the "System of the Year."

December 1999

Corporate restructuring of TDHC is completed and company is reconstituted under the Ontario Business Corporations, Act as a private, for-profit company with Borealis Penco and the City of Toronto each owning 50% of the new company. The company is re-named Enwave District Energy Limited and officially begins operations in January 2000.


Phase II of DLWC design work is completed with plans to expand the chilled water distribution system north on York Street to Wellington Street.


Company is re-branded as Enwave Energy Corporation to reflect its new vertically integrated and customer focused business strategy.

Enwave Energy finalizes plans to build a cogeneration plant at its Walton Street Steam.

Three 5 km pipes are lowered into Lake Ontario in preparation for the Deep Lake Water Cooling system.


Enwave's Deep Lake Water Cooling system is launched on August 17, 2004.


On October 31, 2012, Enwave was purchased by Brookfield Asset Management Inc., a global alternative asset manager with over $150 billion in assets under management.  Brookfield has over a 100-year history of owning and operating assets with a focus on property, renewable power, infrastructure and private equity.  Brookfield is listed on the New York and Toronto stock exchanges under the symbol BAM and on Euronext under the symbol BAMA.

Enwave's history

Enwave Energy Corporation was established more than 20 years ago as a non-profit cooperative. At that time, it was known as the Toronto District Heating Corporation and its original mandate was to provide efficient, environmentally-friendly heating to institutional and government buildings in downtown Toronto.

In the two decades that followed its creation, the company tried to keep pace with the burgeoning growth of Toronto's downtown core by expanding its steam service to include users in the commercial and entertainment sectors. However, its not-for-profit corporate structure and restrictive legislative covenants made it difficult for the company to raise the capital needed to finance growth.

In 1998 the company's Chairman, Dennis Fotinos, initiated a restructuring plan that ultimately gave rise to the private, for profit entity called Enwave. Privatization brought the capital and resources to develop Deep Lake Water Cooling (DLWC) – an innovative method of air-conditioning buildings– and the financial discipline to make the company profitable.

By the time DLWC was commissioned in 2004, Enwave had become a market leader in sustainable energy. With the financial support of its new shareholders, the City of Toronto and the Ontario Municipal Employees Retirement Savings System (OMERS), Enwave was no longer just a district heating company but a fully-integrated energy services provider.

Today, the company owns and operates three modernized steam plants and a new state-of-the-art cooling plant in downtown Toronto. Enwave also manages a large district energy plant in Windsor, Ontario.

With 40 kilometers of pipes buried deep in the municipal rights-of-way, Enwave distributes steam and chilled water with unsurpassed reliability to more than 51% of the potential market in Toronto and to a significant portion of the Windsor market as well.

Enwave's customers include government and institutional buildings; sports, convention, and entertainment facilities; hotel, residential, and commercial complexes; telecommunication hubs; and the Windsor Casino.

Enwave is owned by Brookfield Asset Management Inc., a global alternative asset manager with over $150 billion in assets under management. It has over a 100-year history of owning and operating assets with a focus on property, renewable power, infrastructure and private equity.  Brookfield is listed on the New York and Toronto stock exchanges under the symbol BAM and on Euronext under the symbol BAMA.

1 – Green Toronto: Enwave received the Green Toronto Award. David Miller, Kevin Loughborough.

2 – Laplante and Hayter East Hoarding: This is the hoarding used when the chiller line was put in along Laplante and Hayter Sts.

3 – Belleville Yard: This is the Bellville yard where the intake lines were assembled before traveling down Lake Ontario in pieces to be joined to the intake network at the shore line and then deployed to the lake bottom. In the picture you can see the cement anchors (the whitish half circles) and the lengths of pipe being assembled towards the front of the picture. This was taken in late 2003.

4 – CN Tower – Deep Deployment: This is the best picture taken on the day of deployment. It shows the incoming worsening weather on the left side of the picture and looks towards the shore and city. 2004

5 – Drilling Machine: This was the machine that was used to dig the tunnel for DLWC.

6 – ETL Boring of tunnel, John St. Pumping Station: This is the boring of the tunnel for the (ETL) Energy Transfer Lines to John St. Pumping Station. The other picture of the borer aligns with this one as it depicts the machine that dug this tunnel. This photo was taken in 2003.

7 – Tunnel borer going into the ground: Tunnel borer going into the ground on site in the vicinity below the John St. Pumping Station, 2003.

8 – Tunnel – welder: The Chiller tunnel being worked from the inside. 2003

9 – Intake Site: This is when they were working on the intake site on the outer lake side of the Toronto Island. You can see a Ward’s Island Cottage on the left side of the picture. It was probably taken in 2002 or 2003.

10 – Men pulling pipe: On site at the intake, joining the intake pipe to the on land site. 2004

11 – Intake Aerial of IFP: Aerial shot of the Island Filtration Plant (IFP). You can see where the intake lines enter in the foreground. 2004

12 – Tug pulling pipe: Deployment time. Tug pulling the pipe into the Toronto Harbour.

13 – Tug pulling pipe: This is an even better shot of the tug pulling the pipeline. All three of the lines are in this shot. One being pulled and two in place on the right of the picture.

14 – Borer being lowered: This is the borer after it’s been lowered into the shaft at York St. and Front by the Royal York. It’s being lined up ready to drill the tunnel. 2003

15 – Heat exchanger panel: One of the heat exchanger panels installed between the John St. pumping station and the Chiller Plant. 2004

16 – Men working in tunnel: Men working in the newly bored tunnel from the John St. Pumping Station. 2003

17 – Inside of tunnel: This is what the inside of the tunnel looks like. Pipes running overhead, the intake and return piping side by side. The worker gives you an idea of the sizes. 2004

18 – W – CU Intake Connect: This is the final hookup of the intake piping to the island filtration plant. The picture was taken for the Belleville site. 2002-2003

19 – Heat exchanger: A bigger picture of one of the heat exchangers in place.

20 – Drilling head being lowered: Drilling head being lowered into the Wellington St. shaft. 2004

21 – Tunnel CW Pipe Concrete Encasement: This shows what the tunnels look like completed. This is the Wellington St. Shaft. 2004.