The Ontario Power Authority's "peaksaver" program, activated for only the second time this summer on July 20, saved an estimated 45 megawatts of energy Â– enough to power more than 11,000 homes.
The program was first used this summer on July 7, and the OPA expects it will be activated up to 10 times before the season ends.
The program works when a special switch is installed in homes and small businesses to temporarily power down central air conditioning in order to manage electricity demand during peak energy-wasting hours, weekdays from 1-5 p.m., said Toronto Hydro spokesperson Denise Attallah.
The device works by allowing a wireless signal to cycle air conditioning with "minimal impact on comfort levels," the OPA said in a statement.
The peaksaver kicks in only after "a couple of hot days or heat wave," said Attallah. This was certainly true of the GTA, as Meteorologist Geoff Coulson, of Environment Canada, estimated that temperatures would soar to about 30C this weekend and the humidity could make it feel more like 40C until a cold front moves in.
Homes and businesses in the GTA constitute about half, or 45,000, peaksaver customers, said Attallah.
"Everyone in Ontario benefits when peaksaver is activated," said Sean Brady, the director of demand response and industrial programs for the OPA, in a written statement.
The program works in conjunction with the OPA and local electricity distribution companies across the province. Homeowners or small business owners who install the device receive $25 as well as saving money on their electricity bill, the authority said.
Last summer, residents reported they hardly noticed the cycle of lowered air-conditioning because it is never turned off completely.
By year's end, the OPA expects to offer 26 conservation programs. It wants Ontario to invest $10.2 billion in conservation over 20 years.