How to size a home battery without overspending
Bigger is not always better. Here is a simple way to match battery capacity to your evening use and your solar array.
The most common question we hear after a solar quote is how big the battery should be. The honest answer is usually smaller than people expect.
Start with your evening use
Look at what your home draws between sunset and bedtime. For many households that is 5 to 9 kWh. A battery that covers this window does most of the useful work.
Check your daytime surplus
A battery can only store what your panels produce beyond your daytime use. If your array is small, a large battery will rarely fill up.
- Evening use sets the target size
- Daytime surplus sets the upper limit
- Modular batteries let you add capacity later
During your site visit we read your meter data and show you two or three sizes side by side, with the payback for each.
Have a question about your own roof or bill? Our advisors reply within one working day.
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