If there are already panels on your Enfield roof, the question has usually moved on from whether solar works to what happens to the power you are not using at the time. A battery is the usual answer offered, and it can often be added to an existing array, though the details depend on what is already on your wall. You are not alone in asking: DESNZ records about 2,752 solar PV installations across the London Borough of Enfield at the end of 2025, a count that runs from rooftops to larger sites.
This guide covers how a battery is added, what changes on paper and what it costs, using Enfield’s own figures where they exist. For the roof itself, including Enfield’s 22 conservation areas and their Article 4 directions, see our page on solar panels in Enfield.
What the Enfield count does and does not say
DESNZ’s figure is borough-wide, totals 14.29 MW and counts installations of every size, so it is not a count of homes or of batteries. DESNZ also notes that many 2025 installations could not yet be assigned to a council area when the figures were first published, so Enfield’s count is likely to rise in later editions. The council has a programme of its own: in April 2025 it said it had secured more than £5 million from the Warmer Homes: Social Housing Fund Wave 3.0, plus more than £7 million of its own budget, to fit insulation, energy-saving measures and solar panels to more than 400 council homes.
Start with a year of your own readings
An existing array gives you something no model can: your generation meter. As a reference, PVGIS 5.3 estimates that a 4 kWp array facing due south at 35° in central Enfield makes about 3,955 kWh a year, with about 476 kWh in June and 139 kWh in December, so December is roughly 29% of June on our arithmetic. If your readings run well below that, shading or orientation may be the reason, and a battery sized from the model would be too big for your roof. Bring a year of readings and your bills to the survey.
Two ways to connect the battery
The first route keeps your existing solar inverter and adds a battery with its own inverter beside it. The second replaces the existing inverter with a hybrid unit that runs the panels and the battery together. Which suits depends on the age and model of what is on your wall and how much life it has left; inverters typically carry shorter warranties than panels, which are designed to last 25 to 30 years, so on an older array the inverter may be nearer its end than the roof is.
Space matters as much as electronics. In Grange Park, where 18.3% of households live in detached houses, there is often a garage or utility room to take a second unit. In Southbury and Jubilee wards, where terraces make up around four in ten homes, wall space near the consumer unit is tighter, which can favour one hybrid unit over two boxes. Hallways and the space under the stairs are escape routes and best kept clear.
The paperwork for a bigger system
Adding a battery adds inverter capacity, and UK Power Networks looks at the total. Enfield town centre sits in its Eastern Power Networks licence area. Under ENA EREC G98, type-tested generation up to and including 16 A per phase (3.68 kW) is notified before commissioning or within 28 days after; above that, a G99 application must be approved before work starts, and a 4 kW inverter, at 17.39 A, is already just over the line. An Enfield array that went in under G98 can cross it once a battery inverter sits beside it.
UK Power Networks automatically approves an application where the maximum export, after any export limitation, is under 5 kW, and its Smart Connect service handles G98 and G99 forms for solar PV and battery storage. The installer does all of this on your behalf, and there is nothing to pay UK Power Networks unless your Enfield supply needs upgrading first.
What a retrofit costs, and what it gives up
The Energy Saving Trust puts home batteries between £1,500 and £10,000, with a 5 kWh system around £4,600 and a typical home system at 10 kWh, and gives a typical lifespan of about 10 to 12 years; our guide to how long solar batteries last covers what that means. The Trust also says fitting storage at the same time as panels costs less than a separate visit later, and a retrofit gives that saving up. VAT is not a penalty: since 1 February 2024, batteries installed in homes have qualified for the zero rate on their own, and the rate stays at 0% until 31 March 2027 before reverting to 5%. With 77.2% of Bush Hill Park households owning their home against 36.4% in Ponders End (Census 2021), who pays, and who decides, varies sharply across the borough.
What a battery will not do
It will not carry an Enfield home through winter. With December at about 29% of June on a south-facing roof, a battery is sized to your evening use across the sunnier months, not to self-sufficiency; our guide to what size home battery you need starts from your own usage. Nor will it keep the lights on in a power cut by default. A standard grid-tied battery shuts down with the grid, and backup needs a backup-capable inverter or gateway, an automatic changeover and separate circuits, designed in and priced as its own line. Our page on battery storage in Enfield covers placement and backup in more detail, and the solar panels in North London hub covers the boroughs around Enfield.
Sources: DESNZ, Renewable electricity by local authority, 2014 to 2025 (published 29 September 2026), Enfield, Solar PV sites and capacity, end of 2025, as first published; London Borough of Enfield, Climate action, and Warm Homes Local Grant pages; GOV.UK, Warm Homes: Local Grant successful local authorities (updated 2 July 2026); PVGIS 5.3 (European Commission JRC), PVGIS-SARAH3 2005–2023, run 15 October 2026; ONS Census 2021 via Nomis, TS044 and TS054 by 2022 ward; Energy Networks Association, EREC G98 Issue 2 (10 March 2025); UK Power Networks, Smart Connect, and Solar and storage: cost, time and what’s involved; UK Power Networks Open Data licence boundaries (December 2024); Energy Saving Trust, Battery storage (updated 19 August 2026); HMRC VAT Notice 708/6; Ofgem, Smart Export Guarantee.