This experiment was run from 2023Nov1 to 2024May1.
The input variable represents the kWh in storage on 2023Nov1. This input storage was adjusted to keep the graph below above zero at all times.
The model also calculates how many days where zero PV surplus occurred in any hourly slice during that day. This represents the grey cloudy 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 solar PV production exceeds the daily home load.
The model also computes some rough numbers associated with the seasonal storage amount represented by this input variable. These are shown here.
While this model represents only solar PV and 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 solar PV 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.
The IEA states that globally there is 8500 GWh of pumped storage which represents 90% of all grid storage. Using the 4.3MWh/home result from this study this amounts to enough storage for ~2M homes. This is only 70% of the number of single family homes in Ontario. This illustrates the chasm between the prevailing renewable narrative and season storage reality.
Homestead1 has a number of south facing windows. As such on a sunny winter day my home receives a lot of passive solar heating. This can be easily seen in GSHP electrical consumption in sunny hours of a typical sunny day such as 2024 Feb 03.
One can clearly see the inverse relationship between GSHP load and PV output. This is due to passive solar heating in homestead1. This result offers a clue to a possible solution to the seasonal storage challenge: simply store seasonal solar heat in addition to solar PV electrons.
The model also contains a scaling factor for the PV array at homestead2. One could ask the question
“What if the solar PV array at Homestead2 was doubled in size?”
This is what the model produced for dataset up to 2024Mar1.
As expected adding more solar panels cannot fix a lack of sun problem in mid winter. What it can do, however, is lower the seasonal storage requirements somewhat. The storage drawdown start date is delayed a few weeks into Nov and ends a few weeks earlier at beginning of Feb.
Doubling the solar PV from 16kW to 32kW will mean on average a surplus of 20MWh per year over and above that which is required annually by homestead 1 including the top up of homestead1’s seasonal storage. There has to be a seasonal load available in the summer months to absorb that surplus. If that load is simply more storage we are back to same problem we have with seasonal storage; unrealistic GWh requirement.. If that load is some year round load such as an EV then again we will need seasonal storage to navigate the winter months.