Battery storage — Surrey
Battery Storage Cobham
Home batteries for Cobham homes, with or without solar panels — sized from your actual usage, with the costs, the seasons and the power-cut reality explained before you commit to anything.
Battery storage in Cobham is mostly a garage-and-utility-room job. The town's detached and semi-detached houses on generous plots in Fairmile, Downside and Stoke D'Abernon usually have somewhere sensible for a battery near the meter, so the harder questions are how big a battery your evenings need and whether you want backup. If you have not looked at the roof yet, read solar panels in Cobham first; this page is about the battery: where it goes, who is told, and what it does in a power cut.
Elmbridge's own figures show why the question comes up so often in KT11. DESNZ records about 2,574 solar PV installations of all sizes across the borough at the end of 2025, a 21.87 MW total, and DVLA counts 6,523 privately kept plug-in vehicles there at the end of June 2026, up from 5,249 a year earlier. A big house with two cars and a home office has a very different evening load from a Street Cobham cottage, so our battery storage guide starts from your usage and tariff, and says when a battery is not worth it.
Quick answer
Battery storage in Cobham:
- Cost: the Energy Saving Trust puts home battery storage at £1,500 to £10,000, with a 5 kWh system at around £4,600; your own figure comes from a survey of your usage.
- Seasons: PVGIS estimates a 4 kWp south-facing array in Cobham makes about 487 kWh in June but about 135 kWh in December — size the battery for your evenings, not for summer.
- VAT: residential battery installations carry 0% VAT until 31 March 2027, then 5% from 1 April 2027.
- Grid: central Cobham is on UK Power Networks's South Eastern Power Networks network; the installer notifies or applies to the operator depending on the system's size.
- Power cuts: a standard grid-tied battery shuts down when the grid does; backup needs to be designed in from the start, and we will tell you whether it is worth it.
- Who fits it: HCE is a NAPIT member (73495), MCS-certified for solar PV and battery storage via NAPIT, and a HIES Consumer Code member.
Figures: Energy Saving Trust (batteries, updated 19 August 2026) · HMRC VAT Notice 708/6 · PVGIS 5.3 (European Commission Joint Research Centre) · Ofgem RIIO-ED2 annual report 2024/25. Each is cited in full further down this page.
Where a battery fits in Cobham's homes
The 2021 Census counted 3,721 households in Cobham and Downside ward: 30.9% in detached houses, 27.6% in semis, 18.4% in terraces and 19.2% in purpose-built flats, with 65.3% owning their home outright or with a mortgage. In the detached houses of Fairmile and the semis around Downside, a garage, utility room or side wall by the meter is the obvious home for a battery, with a short cable run to the consumer unit. Large detached houses sometimes have the meter in one place and the garage across the drive, which the survey checks. Lofts are a fallback, because of heat, cold and service access.
The older terraces of Street Cobham and Church Cobham are where it gets harder, with little side access and some homes inside conservation areas. Cobham has three: the main Cobham Conservation Area of 1973 around Church Street, Mill Road and River Hill, The Tilt, and Cobham Plough Corner. There, keep the battery indoors or on a rear wall, and for listed buildings such as Church Stile House or Cedar House speak to Elmbridge Borough Council before anything is fixed to the fabric. The 19.2% in purpose-built flats need the freeholder's agreement, and the 19.6% of the ward's households renting privately need the landlord's.
What a Cobham roof generates through the year
A battery earns its keep by moving daytime generation into the evening, so the shape of the year matters more than the annual total. We ran the European Commission's PVGIS 5.3 (European Commission Joint Research Centre) for Cobham itself, for a 4 kWp array at 35° facing due south with 14% system losses:
- 3,990 kWh a year in total
- 487 kWh in June and 491 kWh in July
- 135 kWh in December and 154 kWh in January
In summer a modest array fills a battery most days; in midwinter it rarely will, and the battery's job shifts to storing cheaper off-peak electricity if your tariff offers it. That is why we size storage from your evening usage and tariff, not from the sunniest month. East- or west-facing roofs and shading change these figures more than the town does — which is what the survey measures.
Method: PVGIS 5.3 (European Commission Joint Research Centre), 4 kWp, 35° tilt, due south, 14% system losses, building-mounted, PVGIS-SARAH3, 2005–2023, monthly output, run 15 October 2026.
The grid and power cuts in Cobham
For a KT11 address the network operator is UK Power Networks: the town centre is in its South Eastern Power Networks licence area, about 7 km from the nearest other one. Your installer tells UKPN about a battery rated up to 16 A per phase (3.68 kW) under G98, before commissioning or within 28 days after. A bigger system, which a large Cobham house with high evening use may want, needs a G99 application approved before the work starts, though UKPN says it approves automatically where maximum export, after any export limitation, is under 5 kW. The 3.68 kW line is about the inverter's output, not the battery's kWh.
In a power cut, a standard grid-tied battery shuts down with the grid, by design, so it cannot feed a network engineers are working on. Backup has to be designed in from the start, with a backup-capable inverter or gateway and a separate circuit for the essentials, at extra cost. On a large Fairmile house the circuit list matters: a home office, heating controls or a freezer may be worth backing up, while an electric shower or oven is not. We will set out what backup would cost and whether it makes sense for you.
Ofgem's reported 2024/25 figures for South Eastern Power Networks show about 42.2 supply interruptions per 100 customers and about 30.4 minutes lost per customer over the year, against 39.7 and 35.1 across Great Britain. Source: Ofgem — RIIO-2 Electricity Distribution: annual report 2024 to 2025, supplementary datafile, sheet "Ch2 outputs - reliability" (CI and CML performance, planned and unplanned).
Local facts, sourced
Cobham and home batteries in numbers
Every figure below comes from a named public source.
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DESNZ records about 2,574 solar PV installations of all sizes across Elmbridge borough at the end of 2025, with 21.87 MW of capacity.
Source: DESNZ, Renewable electricity by local authority 2014 to 2025 (published 29 September 2026), solar PV sites and capacity at the end of 2025, as first published
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DVLA records 6,523 privately kept plug-in vehicles across Elmbridge at the end of June 2026, up from 5,249 a year earlier (about 24% more).
Source: DfT and DVLA, VEH0142 licensed plug-in vehicles by local authority, privately kept, end of June 2026 against end of June 2025 (published 23 September 2026); percentage change is our arithmetic
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DESNZ estimates that 10.09% of homes in Elmbridge borough have no mains gas connection (2024).
Source: DESNZ, Subnational estimates of properties not connected to the gas network, 2024 (published 18 December 2025)
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PVGIS puts a 4 kWp south-facing array in Cobham at about 135 kWh in December against 487 kWh in June: December is about 28% of June, roughly 4.4 kWh a day.
Source: European Commission JRC, PVGIS 5.3 (4 kWp, 35°, due south, 14% losses, building-mounted, PVGIS-SARAH3 2005–2023), run 15 October 2026; ratio and daily averages are our arithmetic
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Cobham is in UK Power Networks' South Eastern Power Networks licence area, with the town-centre point about 7 km from the nearest other licence area, so battery notifications go to UKPN.
Source: UK Power Networks, licence boundaries (Open Data Portal, December 2024); NESO, GIS boundaries for GB DNO licence areas (May 2024)
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Census 2021: Cobham and Downside ward's 3,721 households are 30.9% detached, 27.6% semi-detached, 18.4% terraced and 19.2% purpose-built flats.
Source: ONS Census 2021, TS044 accommodation type (Cobham and Downside ward)
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35.0% of Cobham and Downside ward households own their home outright and 30.3% with a mortgage; 19.6% rent privately.
Source: ONS Census 2021, TS054 tenure (Cobham and Downside ward)
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Cobham has three conservation areas: Cobham (designated 31 July 1973), The Tilt (1979, extended 2015) and Cobham Plough Corner (1990).
Source: Elmbridge Borough Council, Cobham, The Tilt and Cobham (Plough Corner) conservation area pages
Data last reviewed: October 2026
What a home battery costs in Cobham
The honest national anchor is the Energy Saving Trust's: home battery storage ranges from £1,500 to £10,000, a 5 kWh system costs around £4,600, and a typical home system might be 10 kWh. Energy Saving Trust also says there is no exact formula — sizing comes from your own consumption, that a battery's typical lifespan is about 10 to 12 years, and that fitting storage at the same time as panels costs less than a separate visit later.
Residential battery installations carry 0% VAT until 31 March 2027, reverting to 5% from 1 April 2027. Export payments under the Smart Export Guarantee are set by each supplier and must be above zero — they change on short notice, which is why we never print one. Our own price comes from a survey of your usage, tariff and wiring, and arrives itemised — the battery, the inverter or hybrid unit, the network notification, commissioning and warranties as separate lines.
When we would tell you not to: if your evening usage is low, if your tariff gives you little difference between peak and off-peak, or if a smaller solar array would already cover what you use in daylight, a battery can take a long time to pay its way — and we will say so rather than sell you one.
Sources: Energy Saving Trust — Battery storage (updated 19 August 2026) · HMRC — VAT on energy-saving materials and heating equipment (VAT Notice 708/6) · Ofgem — Smart Export Guarantee.
More for Cobham homes
Most batteries are fitted alongside panels, so start with what solar panels in Cobham would generate on your roof; for the wider picture, see how we approach homes across Surrey, or our main battery storage guide for the products and how sizing works. For a longer local read, see Cobham in December and June: how big should a battery be?.
We also cover battery storage in Esher, home batteries in Weybridge and Walton-on-Thames battery installation advice.
Cobham battery questions
Can I fit a battery in a Cobham flat?
Check the lease before anything else. Purpose-built flats are 19.2% of Cobham and Downside ward's 3,721 households (Census 2021), and a lease normally needs the freeholder's or management company's written consent for fixed equipment; tenants need the landlord's, and 19.6% of the ward's households rent privately. If the flat has its own garage in a block, that is often the only realistic location, as communal stores and corridors are rarely agreed. And without panels on a roof you control, the battery only pays if your tariff has a real off-peak rate to charge from.
Will a battery keep my Cobham home running in a power cut?
Not by default. A standard grid-tied battery shuts down when the grid fails. Backup needs a backup-capable inverter or gateway and a separate circuit for the essentials, at extra cost, decided before installation. Cobham's operator is UK Power Networks (South Eastern Power Networks), the people to contact about a power cut. On a larger house the choice of circuits matters most, so tell us at the survey what genuinely has to stay on.
Is a battery worth it with an EV in Elmbridge?
Often, for houses with high evening use and a cheap overnight tariff. DVLA counts 6,523 privately kept plug-in vehicles in Elmbridge (end of June 2026), up from 5,249 a year earlier. The car usually charges overnight; the battery covers the house in the evening. Two practical points: a home charger installation carries 20% VAT, unlike the battery's lower rate set out above, and if UK Power Networks finds your supply cannot take the extra load, an upgrade comes first, with cost and timing that vary by project. On a big Fairmile or Stoke D'Abernon plot, the charger and battery may also sit at opposite ends of the house, which the survey prices honestly.
Can I fit a battery in a listed house in Church Cobham?
Usually, if the battery stays inside or in an outbuilding. The Cobham Conservation Area, designated in 1973, covers the historic Church Cobham core around Church Street, Mill Road and River Hill, home to the Grade II* Ham Manor, Cedar House and Church Stile House and the Grade II Cobham Mill. A battery is not a roof job, so it can usually go in a cellar, garage or utility room, with cables run as discreetly as the building allows. Anything fixed to the fabric of a listed building may need listed building consent, so speak to Elmbridge Borough Council first.