Cheapest times to use air conditioning as heat wave hits Ontario

A heat wave is set to hit southern Ontario this week.

Environment Canada said temperatures will reach the 30s, with humidex values in the 40s.

Most of the region will see highs of 33 C to 36 C on Wednesday and Thursday, with the humidex reaching 40 to 45.

READ MORE: Heat warning issued for parts of southern Ontario

Air conditioners will be working overtime as residents try to cope with the heat.

If possible, you can try to use most of your A/C during cheaper time periods in Ontario to save some money on your electricity bill.

Time-of-use rates

Most residential and small business customers in Ontario pay time-of-use rates, which sees prices change depending on when power is used.

There are three different price periods for the TOU plan: off-peak, mid-peak, and on-peak.

In the summer, the on-peak hours are from 11 a.m. until 5 p.m. on weekdays. The on-peak price currently is 20.3 ¢/kWh.

Mid-peak is from 7 a.m. until 11 p.m. on weekdays, as well as 5 p.m. to 7 p.m. Electricity costs a bit less at 15.7 ¢/kWh.

The cheapest time to use your air conditioning on weekdays is from 7 p.m. to 7 a.m., when the off-peak price of 9.8 ¢/kWh applies. That’s less than half of the on-peak price.

Off-peak pricing also applies on statutory holidays, such as Canada Day this Wednesday, and on weekends.

If possible, you can try to use most of your A/C during during those off-peak periods to limit electricity costs during the heat wave.

Ultra-low overnight

Those who are part of the ultra-low overnight plan also see rates change depending on when power is used, although it works differently.

The on-peak period is from 4 p.m. to 9 p.m. on weekdays. The current rate during those times is 39.1 ¢/kWh.

The mid-peak rate of 15.7 ¢/kWh applies on weekdays from 7 a.m. to 4 p.m., as well as 9 p.m. to 11 p.m.

On weekends and holidays from 7 a.m. to 11 p.m., the off-peak rate of 9.8 ¢/kWh applies.

And by far the cheapest time to use A/C for those on the ultra-low overnight plan is from 11 p.m. to 7 a.m. every day, when the rate of 3.9 ¢/kWh applies.

Tiered

Lastly, those who are under a tiered plan don’t see prices change depending on the time of day.

Tiered rates allow customers to use a certain amount of electricity at a particular price up to a certain threshold. Beyond that threshold, the rate changes.

In the summer, residential customers pay 12.0 ¢/kWh for the first 600 kWh per month. Non-residential tiered customers pay that price for the first 750 kWh.

If that threshold is exceeded, tier 2 pricing of 14.2 ¢/kWh applies.

Most electricity customers in the province can choose either the time-of-use, ultra-low overnight, or tiered plan. The Ontario Energy Board sets electricity rates once a year on Nov. 1.

For more information, visit the OEB website.

Graphics via the OEB