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Home battery installation in Swansea
Updated
Swansea combines coastal terraces, valleys housing and suburban estates. Exposure and slope are practical design inputs.
The houses, not the postcode average
Welsh planning and building control sit alongside the same GB connection framework. Coastal and elevated roofs need a wind-aware array design. The battery still wants shelter.
A battery quote that ignores a steep carry or a salt-exposed external cabinet will not survive the survey.
Hills and terrace parking are the labour variables.
What gets fitted here
Estate and suburban houses with solar and storage are the workable majority.
Annual yield is reasonable for Wales. December is not June.
National Grid Electricity Distribution, yield and a 4 kWp example
A 4 kWp array at 1000 kWh per installed kilowatt is about 4,000 kWh a year before shade. That is the local ceiling on solar charging, not a promise the battery will cycle fully in January.
In Swansea, on National Grid Electricity Distribution, 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 320 times, at 90% round trip. Charge at 13.0p, and value what comes back at 29.6p. Export given up is priced at 10.0p. About 3024 kWh a year of the charge is treated as spare solar from 6 kWp that might otherwise have been exported. Delivered energy is about 3888 kWh. After charging cost and lost export, the figure saves about £740 a year. Set that against £8,805 fitted, which is a September 2026 illustration at the temporary 0% residential rate, not a quote. That is a simple payback of about 11.9 years on these assumptions. Nudge the night rate up by 4p and see if you still like it.
What I would not sign in Swansea
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 £8,805 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 pay the bulk of £8,805 before the DNO route for a 5 kW inverter is known.
Slope and salt are the local extras. A flat inland quote with mileage added is incomplete.
Common questions
Is the price on this page a quote?
No. £8,805 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 £8,805 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 29.6p 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.