Ontario Energy Market Highlights - 2025-11-05
🌦️ Weather Outlook
Ontario will experience a mainly cloudy day, with temperatures ranging from 3.0°C to 16.0°C across the province. Northern zones (Thunder Bay, Sudbury) will trend colder and overcast, with widespread single-digit highs, while southern hubs (Toronto, London, Windsor) will remain milder, reaching the low-to-mid teens under persistent cloud. The cooler north–south contrast will favor higher space-heating load in the morning and evening, while the cloud deck will suppress solar output. Cloud-driven stability and a modest pressure gradient will support moderate, variable wind generation, which will help offset midday demand but will still require dispatchable resources during the evening ramp.
⚡ Demand
System demand will start near 13,757 MW overnight, will build through a steady morning ramp, and will settle into a muted midday plateau before peaking around 17,914 MW at HE18. Cooler temperatures and shorter daylight will reinforce the classic shoulder-season evening peak as lighting and heating loads increase after sunset. Looking ahead, next week’s peak forecasts will approach 20,869 MW, signaling rising electric heating requirements and tighter evening conditions if renewables underperform.
đź’° Energy Prices
- Day-Ahead (DAM) prices will range between $42/MWh and $104/MWh.
- Pre-Dispatch (PD) prices will fluctuate between $38/MWh and $118/MWh, with the intraday high of $118/MWh anticipated at HE21.
The price stack will point to generally adequate supply during off-peak hours, with emerging tightness late day. The premium in PD—especially the HE21 spike—will reflect the evening demand ramp, modest solar contributions under cloud, potential wind variability into the evening, and the need for incremental gas and hydro flexibility against a backdrop of sizable planned outages.
🔋 Generation Mix
- Nuclear will remain steady near 7,354 MW, anchoring baseload.
- Hydro will vary between 2,968 and 4,186 MW, shaping ramps and intra-day balancing.
- Gas-fired generation will scale up to roughly 4,176 MW during the evening ramp to firm supply as renewables fade.
- Wind will range from about 1,459 to 3,962 MW, providing material but variable contributions.
- Solar will peak near 111 MW around midday under cloud-limited irradiance.
Collectively, nuclear and hydro will underpin reliability, wind will temper midday prices when available, and gas will provide the critical firmness needed for the late-day peak.
🚧 Planned Outages
Today’s planned outages will sit near: Nuclear 5,830 MW; Hydro 2,531 MW; Gas 2,685 MW; Wind 1,781 MW. Outage levels will remain seasonally elevated, but supply adequacy will be maintained with dispatchable hydro and gas coverage. Absent new maintenance events, outage profiles will likely trend steady in the near term, with typical fall maintenance winding down gradually as winter approaches.
âś… Summary
Ontario will see a cool, cloudy day that will drive a pronounced evening peak near 17.9 GW. Baseload nuclear will remain stable, while hydro and gas will manage ramps amid variable wind and minimal solar. Prices will be moderate to firm, with PD signaling tighter conditions into HE21. Overall reliability will remain sound despite elevated outages, though evening hours will warrant close monitoring as heating load builds and renewables ease.
