Make sure everything that runs gets switched on at that time.
Can also store energy thermally. Ex: during that hour have a bunch of electric heaters go on in winter, since the power is free just get it as warm as you can handle in the house for that hour. Then when the hour is over your regular heat, whether it's electric or gas, won't have to run for a bit. Could get smart with a hot water based system too to store even more heat.
Anything like fridge, freezer etc could also be turned off automatically say, an hour before, then turn on during the free hour. Anything that's on UPS could also be set to run on battery right before the power is free. I suppose every little bit could help and it would essentially be free to do this.
Crossed my mind to get battery storage though to store power off peak and then run off batteries on peak. But reality is, the usage is not really the expensive part of the hydro bill, it's all the fixed fees. So reducing usage in one way or the other hardly does anything.