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Home battery installation in London
Updated
London housing splits into Victorian and Edwardian terraces, mansion blocks, converted houses and new towers. A battery that is easy in a suburban garage can be impossible in a block where the cupboard, the riser and the external wall are all demised differently.
The houses, not the postcode average
Roof space is often split across butterfly roofs, dormers and cramped lofts. South-facing inner-suburb roofs can still produce a useful summer charge, while mansion-block residents may have no roof demised to them at all.
The job usually turns on the lease, the managing agent and where a heavy cabinet can sit without blocking an escape route. Controlled parking and congestion also change how long an installer is on site.
Congestion, parking suspensions and upper-floor carries add labour that a national package price rarely shows.
What gets fitted here
A common surveyed job is a hybrid battery on a terrace with a short cable run to a rear garage, or a flat where the survey stops once the freeholder will not allow equipment in a communal area.
Winter solar across the capital is a thin trickle. A battery sized only for summer export will sit half empty in January unless a time-of-use tariff is doing the charging.
UK Power Networks, yield and a 4 kWp example
A 4 kWp array at 980 kWh per installed kilowatt is about 3,920 kWh a year before shade. That is the local ceiling on solar charging, not a promise the battery will cycle fully in January.
In London, on UK Power Networks, 5 kW sits above the 3.68 kW G98 line, so this wants a G99 application before anyone energises it. Export can still be capped. Agree that before the inverter is ordered. The figure uses 13.5 kWh and 6 kWp, which is enough to tell two quotes apart if they assumed something else.
Take a 13.5 kWh pack, cycled about 280 times, at 90% round trip. Charge at 13.0p, and value what comes back at 27.2p. Export given up is priced at 6.0p. About 2646 kWh a year of the charge is treated as spare solar from 6 kWp that might otherwise have been exported. Delivered energy is about 3402 kWh. After charging cost and lost export, the figure saves about £651 a year. Set that against £10,038 fitted, which is a September 2026 illustration at the temporary 0% residential rate, not a quote. That is a simple payback of about 15.4 years on these assumptions. Nudge the night rate up by 4p and see if you still like it.
What I would not sign in London
Where the job is a qualifying install in a home, the 0% rate runs to 31 March 2027 and is due to become 5% after that. This figure prices the work at £10,038 on that basis. It does not apply to a shop, and it does not apply to a battery you buy and fit yourself.
I would not compare a £10,038 headline with another until usable kWh and the fate of any existing inverter match.
A side-return garage in Walthamstow and a mansion-block cupboard in Marylebone are not the same quote, and the paperwork should say which one was priced.
Common questions
Is the price on this page a quote?
No. £10,038 is a September 2026 illustration for a 13.5 kWh example at the temporary 0% residential rate. Your survey replaces it.
Will it stay on in a power cut?
Only if a gateway or essential-load board was designed and paid for. A standard grid-tied battery turns off with the grid. On this 13.5 kWh example the inverter is 5 kW, and backup is still a separate line.
What paperwork should I keep?
Keep the MCS certificate where the job is certified, the electrical certificate, the DNO record, the schematic, the warranty registration and a photo of the schedule. For an illustrated £10,038 job, that folder is part of what you bought.
What if the cheap rate is not 7p?
Then the figure changes. This page used 13.0p as a charge rate and 27.2p as the rate avoided. A smaller gap means a worse payback. Read the live tariff.
Sources
Want a price for your house?
The figures above are a rough guide. An installer still needs to see your fuse board, where the battery will go, and whether you want power during a blackout.