How Ontario Grid calculates its numbers

We add each generator's latest reported hourly output, in megawatts (MW). Fuel shares divide a fuel's output by that reported total. The selected fuel reveals its units and each unit's output. Map pins use researched plant or nearby place coordinates, so some locations are approximate.

For each fuel, we add its 24 hourly MW readings to estimate daily energy in megawatt-hours (MWh). A fuel's daily share is its MWh divided by all reported generators' MWh that day. Today's bar is partial until all hours arrive.

We group readings from the selected dates by hour of day, then average each fuel's output across days with that hour reported. The share view divides each fuel's average by the total average for that hour.

Daily capacity factor is energy generated divided by the energy a fuel group could make at its reference capacity for 24 hours. Each unit's reference is its highest reported available capacity in the previous 90 days. We add those references by fuel and leave out the unfinished day.

Each cell adds one unit's hourly output for that day, in MWh. Darker colour means more generation on the chosen colour scale. A blank means no report for that unit and day; zero means the unit reported no output.

IESO reports real-time locational marginal prices (LMPs) in $/MWh. We average the five-minute prices within each hour for representative nodes at a station, then give each station equal weight in its fuel's price. Daily prices average the available hours. The system reference averages designated market buses.