Selby Solar Output Month by Month: When Does a Home Battery Actually Fill?
ElectriFusion Solutions · 15 October 2026
A Selby household asking whether a battery is worth it usually gets an annual kWh figure in reply, which is the one number that does not answer the question. What matters is the month. This is a south-facing Selby roof, every month, from the European Commission's PVGIS model.
A 4.85 kW array in Selby, every month
| Month | Output | Average per day |
|---|---|---|
| Jan | 162 kWh | 5.2 kWh |
| Feb | 246 kWh | 8.8 kWh |
| Mar | 409 kWh | 13.2 kWh |
| Apr | 526 kWh | 17.5 kWh |
| May | 595 kWh | 19.2 kWh |
| Jun | 551 kWh | 18.4 kWh |
| Jul | 580 kWh | 18.7 kWh |
| Aug | 529 kWh | 17.1 kWh |
| Sep | 431 kWh | 14.4 kWh |
| Oct | 297 kWh | 9.6 kWh |
| Nov | 203 kWh | 6.8 kWh |
| Dec | 158 kWh | 5.1 kWh |
PVGIS 5.2, SARAH2 radiation database, Selby town-centre coordinates, south-facing at 35°, 14% system losses, fetched 15 October 2026. Annual total 4,685 kWh (966 kWh per kW), about 1.4% less than Doncaster. Modelled averages, not a guarantee for any particular roof.
The best month here is May at 595 kWh (19.2 kWh a day) and the worst is Dec at 158 kWh (5.1 kWh a day), a ratio of 3.8 to one; that ratio, not the annual total, is what a battery has to live with.
For scale: PVGIS puts the in-plane irradiation on that roof at about 1,189 kWh per square metre a year, and the array converts it to 966 kWh per installed kilowatt; a Selby household with the regional average evening load would see the battery cycle fully on about 214 days a year on these figures.
What that means for the battery
Take daytime usage off the top and a 5 kWh battery fills on days the roof makes about 10 kWh or more. In Selby that is Mar, Apr, May, Jun, Jul, Aug, Sep on the monthly averages. A 10 kWh battery is a 16 kWh-a-day proposition from solar alone, which here means Apr, May, Jun, Jul, Aug.
From November to January the average is 5.7 kWh a day. A house that runs a fridge, a router, a kettle and some lighting through the day uses most of that as it arrives, so the battery sees a few hundred watt-hours of surplus, not five kilowatt-hours. That is not a fault with the battery or the panels; it is the latitude.
That something else is the grid
The grid fills the gap. A time-of-use tariff charges the battery overnight at the low rate and the house draws it down through the evening peak; from November to January that is where almost all of a Selby battery's saving comes from, and from May to August the roof does the filling instead. Both halves are rate gap times kilowatt-hours shifted.
Count each day once. A battery that filled overnight has no room for the morning's solar surplus, so on a summer day the saving is the solar or the tariff, not both added together.
So what size for a Selby home?
The evening load decides it. Pull a week of half-hourly smart-meter data: if the house uses 4 to 6 kWh between dusk and midnight, 5 kWh is the size; an EV or heat pump pushes it to 10 kWh, and in Selby that larger unit is working for the overnight tariff more than for the roof. Registration with the network, standalone options and the models we fit are on battery storage Selby; the solar side is on solar panels in Selby.
Questions
Does a home battery work in winter in Selby?
It works, but from the tariff rather than the roof: PVGIS gives a 4.85 kW array in Selby about 5.7 kWh a day across November to January, most of which the house uses as it is generated. On a time-of-use tariff the battery charges overnight and runs the evening peak all winter.
Which months will a 5 kWh battery fill from solar in Selby?
On the PVGIS monthly averages, Mar, Apr, May, Jun, Jul, Aug, Sep, when the roof makes 10 kWh or more a day after daytime use. A 10 kWh battery fills from solar alone in Apr, May, Jun, Jul, Aug.