Hold onto what your panels generate.
A battery banks your solar generation during the day and releases it in the evening, instead of it being exported to the grid at a lower rate than you’d pay to buy it back. Solar and battery installations are also currently zero-rated for VAT, a relief that runs until 31 March 2027.
Built for a working household.
A lot of London households are out of the house for a large part of the day, commuting into a workplace elsewhere in the city, right when panels are generating the most. Without a battery, that generation is exported at whatever rate your supplier offers, often a fraction of what you’d pay to import the same unit back that evening.
Time-of-use tariffs built around solar and battery households typically charge less overnight, often under 10p/kWh, against a peak import rate that can run well over 20p/kWh between 4pm and 7pm. A battery lets you shift your usage to match, rather than paying peak rates for electricity you generated for free that afternoon.
Daytime banking
Store what your panels generate while you’re out, instead of exporting it at a low rate.
Evening release
Use your own stored generation through the 4pm to 7pm peak, when grid electricity costs the most.
Overnight top-up
On a time-of-use tariff, a battery can also top up from the grid during the cheapest overnight window.
How we work out the right size.
Usage pattern
We look at when your household actually uses electricity, not just how much.
Panel output
How much your array generates on an average day sets the ceiling on what’s worth storing.
Tariff check
An export or time-of-use tariff changes the maths on what size pays back fastest.
Right-sized quote
You get a battery sized to your home, not the biggest unit on the price list.
Can I add a battery to existing solar panels?
Yes, in most cases. Depending on your current inverter, we either connect a battery directly or, if it’s an older string inverter, may recommend an AC-coupled battery that works alongside it.
Where does the battery get installed?
Usually a garage, utility room or under-stair cupboard, though some units are rated for outdoor installation on an exterior wall. Space is often tighter on London terraces than on a detached house, so we confirm the best spot at survey stage.
What happens during a power cut?
Most grid-tied battery systems switch off for safety during a power cut, the same as solar panels alone. A backup-capable setup can keep essential circuits running, but this is a specific configuration worth discussing if it matters to you.