My Ontario electricity reporting/estimates now updating through week 4 - which was a big week in 2025, but a cold expensive weekend pushed demand and pricing past even that.
Nuclear was down on the grid - I grudgingly think largely due a Bruce Power choice on outage timing
1/7
Jan 26, 2026 14:17Gas again stepped in to meet demand in Ontario and connected grids.
Exports averaged over 3 GW, while the average Day Ahead Market (DAM) prize for the Ontario zone averaged $134+/MWh
[these graphics from
app.powerbi.com/view... ]
2/7
moving to reporting inclusive of estimates on distributed and curtailed supply, as well as costs, the minor overall change in demand to wk4 ly was accompanied by a greater increase in costs - mostly on nuclear rates meaning less supply for the same costs, and ga
3/7
the surging market rates have widely varying impacts on different consumer classes
Exports are most costly, but Class A and B have prices converge with high market rate.
Class A pricing is up 73% from the wk 4 2020-2024 avg; Class B pricing only 16%
4/7
Weekly "Ontario demand" (IESO grid) was the 5th highest since 2007, and the highest of any winter week.
On a hopeful note, there are 4 'week 4's in the top 12 demand weeks since 2007, so this is typically the depth of winter.
5/7
It was a record week for output fueled by natural gas (maybe with a boost from oil), and the 4th highest average weekly market rate since 2007.
those figures all coming from filtering and sorting of
app.powerbi.com/view...
6/7
Lastly, I'll note the majority of potential supply from 2 hydro facilities capable of feeding directly into Quebec's grid was diverted there - a total of 91 GWh according to my routines' tracking, an average of 540 MW over the entire week.
7/7
My Ontario electricity reporting/estimates now updating through week 4 - which was a big week in 2025, but a cold expensive weekend pushed demand and pricing past even that. Nuclear was down on the grid - I grudgingly think largely due a Bruce Power choice on outage timing 1/7Jan 26, 2026 14:17
