Three older buildings get the green treatment; Potentia
district energy systems reduce gas consumption by 30%
The situation: Old boilers, no central chiller plant and high hot water demand
The three buildings in the Toronto area of Thorncliffe were equipped with seven-year old boilers that had reached end of their service life and were no longer reliable. The buildings also had a higher than average tenant-per-unit ratio, resulting in high domestic hot water use. There was no central chiller plant, ruling out a ground-source heat pump option, since this technology requires balanced heating and cooling loads. However, the buildings were almost fully connected via underground parking lots, excepting a short distance between 71 and 75 Thorncliffe Parkway.
The challenge: Municipal bureaucracy
At this location, we were fortunate in that existing underground parking lots could serve as conduits for a good proportion of our hot water pipes. District energy systems generate hot water at a central boiler plant, delivering it to different buildings via underground pipes. The hot water provides heating and domestic hot water, eliminating the need for boilers in each building. Our project was delayed when the City of Toronto refused to grant permission to install distribution pipes beneath a roadway between 75 and 71 Thorncliffe — the segment not connected by underground parking lot. However, local councilor John Parker, convinced of the merits of the project, helped us work our way through the municipal bureaucracy, which passed a motion allowing the installation.
The result: The Thorncliffe Central Plant delivers
- A well-designed district energy systems delivering superior energy efficiency, plus reduced operating and labour costs
- A 30 percent annual reduction in natural gas use (742,000 cu m) for space heating and domestic hot water
- A reduction in maintenance costs
- A 400 ton reduction in annual carbon dioxide emissions
