Battery Storage
A Guide to Batteries for Solar Panels
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✔ A solar battery is a storage device for excess solar electricity
✔ A solar-plus-storage system saves the average 3-bed house £753 per year
✔ You'll typically cut your carbon footprint by 7% with a solar battery
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Solar panels make wonderful use of one of our best natural resources – the sun – but a typical household ends up wasting around half of its solar energy.
A solar battery can store this electricity for you to use later on. This will help you be more energy independent, cut your carbon footprint by 7% on average, and save 29% more on your energy bills than you would with solar panels alone.
What is a solar battery?
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A solar battery is a device that allows you to store the excess electricity your solar panels generate, so you can use or sell this energy at a later time.
Unless you or the people you live with are at home and using electricity every minute of every day, you’ll have solar power that goes unused.
Typically, you’ll lose 50% of the electricity produced by your solar panels this way – but not when you have a solar battery.
A solar battery can save you a lot of money per year.
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How does a solar battery work?
A solar battery works as an overflow storage unit.
When sunlight hits solar panels, they turn this natural resource into direct current (DC) electricity, before converting it into alternating current (AC) electricity that powers your home.
And when your home is fully powered, any excess solar energy will be rerouted to charge your battery, in much the same way you charge your phone.
You can either get a lead acid battery or a lithium-ion model, which offers faster charging and a higher capacity.
After the sun goes down and your panels stop producing energy, it’ll be time for your solar battery to shine, by providing you with all the energy it’s gathered.
This will happen automatically, with your panels and battery seamlessly passing the baton between them, so you won’t need to worry about monitoring the system.
The sun's time in the sky and the times you use energy at home don't line up perfectly, and a battery solves this problem.
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What size solar battery do you need?
The average three-bedroom household needs an 8 kWh solar battery.
If you live in a house with one or two bedrooms, you'll likely need a battery with 2-4 kWh of capacity.
And if your household has four or five bedrooms, start by looking at 9.5 kWh solar batteries.
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How long does a solar battery last?
Solar batteries usually last for 15 years and come with a 10-year warranty – though their capacity might decline in their later years.
They have to perform repetitive, daily charging and draining cycles, and just like your phone’s battery, this eventually wears them out.
If you buy a top-quality model, the chances are higher that it’ll last beyond its 10-year warranty.
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