The Cliff plant  

Over 100 years ago, in 1918, the Cliff heating plant was built to provide heat to buildings within Ottawa’s Parliamentary Precinct. Designed by architect John A. Pearson, with the assistance of engineer Melvern F. Thomas, the Cliff plant was the first central heating plant of its type in Canada.

The original building was a flat-roofed, rectangular structure with a large brick chimney protruding from the centre. Built from the excavated cliff’s limestone, the plant was designed to blend in with the south bank of the Ottawa River. The roof of the plant was even with the top of the cliff, and the walls displayed 6 tall windows on the first floor and smaller windows on the top levels.

In a time when fireplaces or stoves were the main sources of heat, the Cliff plant incorporated the use of steam and hot water technology for heating. Both of these systems used coal-fired boilers and allowed heat to be distributed to several buildings from one central point. This innovation was termed “district heating” and was the beginning of what is now known as the district energy system.

Since its initial construction, a number of upgrades have been made to the Cliff heating plant energy systems, including the addition of new cooling technology. By 2000, the plant was responsible for heating 51 buildings and cooling 41 buildings connected to the district energy system.

Today, the plant is called the Cliff heating and cooling plant and operates from 2 separate buildings. The heating portion of the plant sits atop the cliff and has 3 saturated steam boilers and 3 superheated steam boilers. The cooling portion of the plant is housed in the original building along the river and has 1 steam chiller and 2 electric chillers.

A new era

Despite energy advancements over past decades, the Cliff heating and cooling plant’s energy technology is outdated, and the existing infrastructure is reaching the end of its service life. It significantly contributes to greenhouse gas emissions and is 25% less efficient than current industry standards.

In stage 1 of the district energy system modernization, the current Cliff plant will be demolished and a new building will be constructed. The plant will continue to heat and cool buildings within the Parliamentary Precinct, including the Centre Block, the Supreme Court of Canada, the West Memorial Building and many others.

The plant will house a new low-temperature hot water heating system and a series of electric chillers. The building will also be equipped with Smart Buildings technology to monitor its energy efficiency.

The architectural design for the new facility, currently being finalized, will feature a curtain wall design, stainless steel stacks and box-like observation decks. At river level, there will be a public meeting area, while the upper plateau will have walkways, seating areas, greenery and spectacular views. The upper and lower plateaus will be accessible to the public and employees by a staircase and an elevator.

On October 6, 2020, the National Capital Commission’s board of directors approved the demolition of the existing Cliff heating and cooling plant. Work on the new building has already started and is on track for completion by 2025.

To learn more about how Public Services and Procurement Canada plans to make federal buildings more environmentally friendly, check out the Greener federal buildings web page. For any questions related to the Energy Services Acquisition Program, you can contact Real Property Services directly.