Many renewable advocates claim that wind + solar make a complementary pairing. Since we have the homestead1 electricity dataset and Ontario publishes its wind power data online we are in a position to run a complementary model for wind. In other words we can answer the following question:
“How much seasonal storage is required in Ontario to carry a GSHP (Ground Sourced Heat Pump) home through the heating months with power supplied exclusively from Wind?”
The IESO dataset for wind gives hourly MW wind totals for the grid. To match the home kWh dataset we need to convert the hourly MW dataset into an hourly MWh dataset. We do this by assuming that between hourly data points the transition is a straight line. This yields the following formula for calculating MWh
MWh(at hour n) = (MW(at hour n) + MW(at hour n+1)) / 2
There is still a mismatch of scale between a single family home consumption and the entire 5GW grid connected wind dataset. We need to scale the wind dataset appropriately to allow a match. In Ontario wind puts 13.8 TWh annually of electricity onto the grid. We know that the homestead1 usage is ~12MWh annually. Doing the math we
Number of possible GSHP powered homes = 13.8 x 1,000,000 / 12 = 1.15M homes
So our scaling input variable in our model will be the number of possible GSHP homes to be serviced by wind on the grid. We will be using numbers in and around 1M homes.
This experiment was run from 2023Nov1 to 2024May1.
There are 2 input variables into the wind model:
Number of possible GSHP homes
Starting storage kWh on 2023Nov1
The input variable starting storage kWh was used to keep the graph below above zero at all times.
Depending on how we scale the wind dataset we need between 1100kWh and 1800kWh of storage per household to navigate the wind deficit during peak GSHP heating season. Because the wind is still plentiful in early part of winter this graph looks a little different from the solar PV graph in the results chapter. Solar PV requires about 2-3x as much seasonal storage to navigate winter, but even 1100kWh household is not economically feasible.
The model also calculates how many days where zero Wind surplus occurred in any hourly slice during that day. This represents the low wind winter days that are all too common Nov, Dec and Jan in this part of Ontario. Unfortunately these are the very months that the GSHP load is highest.
The model also computes a related surplus count; the number of days where Wind production exceeds the daily home load.
While this model computes data for a single Ontario single family home, there are 3M (54% of total housing) such homes in Ontario. If we were to transition these homes to heat pumps for climate reasons, this model gives some indication of the challenges with seasonal storage for Wind in Ontario. In particular it is instructive to examine the battery and pumped water storage options. They would be truly massive if multiplied by 3M single family homes in Ontario.