The maths, in the open.
PowerSave picks a start time from your rate plan. Here is exactly how.
We price each minute of the run across the periods it overlaps, then round to the nearest cent.
We try start times every 15 minutes over the next 24 hours (within any deadline you set).
The cheapest start wins. If two starts cost the same, we pick the earlier one.
Laundry at 5:30 PM on TOU
Design example: Wed Nov 18 2026, winter weekday, rates effective Nov 1 2026 (18.9¢ on-peak · 9.1¢ off-peak). 3 kWh over 90 minutes.
Round each cost to the cent, then subtract. Electricity cost only.
Dishwasher 1.2 kWh / 2 h from 5:30 PM spans on-peak then off-peak → 20¢ when run now. Sample data.
Equal cost → earliest start.
Done-by limits the search. Quiet hours (10 PM–7 AM) only limit when we suggest you press start.
TOU weekends and holidays, and Tiered plans: “Any time. Same price all day.” We never invent a saving.
Ontario TOU/ULO holiday list from the OEB. If a holiday falls on a weekend, the next non-holiday weekday gets holiday prices.
Estimates are not a bill. We don’t know your appliance’s exact draw, delivery charges, regulatory charges, HST, or the Ontario Electricity Rebate.
The grid price is not what you pay.
Advice comes from your rate plan only. Wherever we show the wholesale market price, we label it: Wholesale market price. Not what you pay.
Open The Grid →| Source | Use |
|---|---|
| Ontario Energy Board RPP | Household rates (reviewed each Nov 1) |
| IESO public reports | Wholesale view on The Grid (~5 min) |
| OEB holiday schedule | TOU / ULO holiday pricing days |
PowerSave is independent. It is not affiliated with the OEB, the IESO or any utility.