Where does Ontario's electricity come from right now?
A snapshot of the provincial grid — like the live IESO dashboard, but it runs fully offline. Pick a moment in the day and watch the mix (and how clean it is) change. Root & STEM — EV Issue, Lesson 2.
How much from each source
Total demand—
Grid carbon intensity—
Renewable + nuclear—
—
Choose a moment in the day above. The mix — and how clean it is — will change.
For the teacher: Ontario's grid is dominated by nuclear and hydro, so it is usually very clean (~30 gCO₂/kWh). But the mix is never fixed. On a cold winter evening or a hot summer afternoon, demand spikes and the grid burns more natural gas — so the same EV charges dirtier at those moments. On a windy spring day, wind can supply a big share and the grid gets cleaner. The key idea: "how clean is my EV?" depends on when and where you plug in. One caveat on nuclear: it emits almost no CO₂ (so it counts as low-carbon here), but it produces long-lived radioactive waste that must be stored safely for a very long time — low-carbon is not the same as no-impact. These are realistic Ontario figures, simplified for teaching; the real live data is at ieso.ca/power-data when you have internet.