On a June afternoon when an early heat wave baked parts of Eastern Canada, Paul Richardson was surprised to notice the smart thermostat in his Ottawa home, usually set to 23 C, was reading 25 C. 

Then he remembered he'd given his hydro company permission to remotely adjust it in exchange for a $75 gift card. 

During heat waves like the one currently blasting southern Manitoba, power-hungry air conditioners strain the electrical grid. Now, instead of pushing power plants to generate extra power by…