Hydro Quebec, my provincial electricity utility, is trialing a dynamic pricing model this winter. It hasn't been rolled out to all residential consumers yet, it's in a trial phase. I applied for the trial and was accepted to participate. I figured that dynamic pricing is inevitable with Quebec's push towards electric cars, so I might as well jump in and see how it goes. My home is already extensively automated, so I should be able to come up with protocols to deal with the peak demand events with a minimum of manual intervention.
The base electricity rates in Quebec are tiered. The first 40 kWh per day are charged at 6.08¢/kWh (1st tier). The remaining energy is charged at 9.38¢/kWh (2nd tier).
The "Rate Flex D" is a dynamic rate where electricity is cheaper than the base rate in winter, except during peak demand events, when it’s more expensive. From December 1st to April 31st of the following year, outside of peak demand events, the price of electricity is below the base rate, so you can save money (4.28¢/kWh for the first tier of 40 kWh/day, and 7.36¢/kWh for the 2nd tier). During peak demand events, electricity is billed at a high price (50¢/kWh). The day before a peak demand event, you receive a notification.
I've been through three days of peak demand events so far. In this post, I'll describe some of my preparation, and how things are going so far.
First, here are some characteristics about my house.
- Large, two story house with full basement. Electrically heated garage on an elevated concrete slab, with basement space below the slab. 3/4 of the basement is finished, 1/4 is utility space housing the fan coil, most of the zoned ductwork, the electrical entrance, and storage space under the garage;
- 400A electrical entrance, with three 200A breaker panels. One panel is designed for critical loads and is connected to a generator transfer switch. There was a generator installed at one time at the house, it has since been removed.
- Principal heat source is a Carrier Infinity Greenspeed 4 ton heat pump with variable speed indoor fan coil, with three stages of backup electric resistance heating. The heat pump can maintain a constant temperature in the house, without electric backup heating, down to about -14C. Below that temperature, the heat pump needs help. The heat pump thermal efficiency drops to 1 at about -20C, where it no longer is effective.
- The forced air ductwork is zoned, with a separate zone for each level of the house - basement, main floor and 1st floor. I upgraded the Infinity system to full zone control this year, and can now control the temperatures on each floor independently.
- There are supplemental electric resistance heaters in most of the rooms in the basement for comfort. These are controlled by programmable thermostats. Now, since the zone heating upgrade, I haven't bothered turning those circuits on since I can effectively control the basement temperature from the principal heating system. Our offices are in the basement, and with COVID confinement, a comfortable working temperature in the basement was one of the prime drivers to do the zone heating project.
- I have extensive Insteon control over lighting. Virtually all lighting in the house, on all levels, is controlled by insteon switches and dimmers.
