Sixty against ten. A car with a 60 kWh battery holds six times the 10 kWh the Energy Saving Trust gives as a typical home battery size, on our arithmetic. Keep that ratio in mind and most questions about putting an EV and a home battery in the same Basingstoke house answer themselves.
The charger side, from estate driveways to Hampshire’s rules on cables over pavements, is on our Basingstoke EV charger page. This guide is about how the two batteries, the one on the drive and the one on the wall, divide the work.
Two batteries, two different jobs
The car’s battery exists to move the car. The home battery exists to move electricity from the cheap or sunny part of the day to the expensive part, usually the early evening, when the kettle, the oven and the television all come on at once. They can share a house and a supply, but they are bought, sized and run on different logic.
That is also why they sit under different tax rules. HMRC’s VAT Notice 708/6 lists residential batteries as energy-saving materials, zero-rated until 31 March 2027 and 5% from 1 April 2027. A home EV charger is not on that list, so its installation is standard-rated at 20%.
The arithmetic, labelled as ours
Take a household using Ofgem’s Typical Domestic Consumption Value from 1 July 2026: 2,500 kWh of electricity a year. That averages about 6.8 kWh a day. A 10 kWh home battery can hold more than a whole average day’s use, which is plenty for an evening.
Now add a car. A full 60 kWh charge is close to nine days of that household’s ordinary electricity, all going into one vehicle. A 10 kWh home battery cannot meaningfully fill it: at a 7 kW charging rate it would be empty in under an hour and a half. These are our sums on the published figures, not measurements from any particular home.
Why the house sets the battery size
The Energy Saving Trust says there is no exact formula for sizing a battery; the answer comes from your own use. Two more Basingstoke figures point the same way. PVGIS puts a 4 kWp south-facing array here at about 488 kWh in June but only about 136 kWh in December, so in winter there is little daytime surplus to store whatever size you choose. A battery sized to the evening load works in every month; one sized to the car would sit part-empty most of the year.
A battery does not give you backup power during a power cut by default, either. That needs a system designed and configured for it, which is a separate conversation.
Where the car fits in the day
Every home chargepoint sold in Great Britain since 30 June 2022 has had to be smart, able to schedule charging into cheaper hours. In practice, the car charges overnight in an off-peak tariff window, straight from the grid, while the home battery covers the evening peak and, where there are panels, soaks up daytime surplus. The two do not compete for the same hours. If you already have panels and want to add storage, our guide to adding a battery to existing solar in Basingstoke covers the coupling choice and the paperwork.
Plug-in numbers across Basingstoke and Deane
DVLA records 6,203 privately kept plug-in vehicles across the borough at the end of June 2026, up from 4,382 a year earlier: 1,821 more, a rise of about 42% on our arithmetic. That counts cars registered to private keepers at their address, not chargers and not households with an EV. Many households here have more than one vehicle: at the 2021 Census, 34.3% had two cars or vans and 12.7% had three or more.
Two cars, a charger and a battery on one supply
Basingstoke sits in SSEN Distribution’s Southern Electric Power Distribution area, and the town-centre point is about 27 km from the nearest other network. A 7 kW charger draws 32 A continuously, and domestic main fuses are commonly 60 A, 80 A or 100 A. Add a second charger, an electric shower and a battery charging from the grid overnight, and a smaller fuse can run short of headroom. Load management, a sensor on the incoming supply that throttles charging while the house is busy, usually solves that without a supply upgrade.
The battery brings its own paperwork. Up to 16 A per phase (3.68 kW) it is notified to SSEN under G98; above that, a G99 application must be approved before work starts. The installer handles both the chargepoint notification and the battery application.
Grants follow different rules too
The charger grant has nothing to do with the battery. The OZEV grant covers 75% of the cost, up to £500 per socket, for renters and people who own and live in flats with private off-street or allocated parking; residential landlords can claim up to £500 per socket. Owner-occupiers of houses get no grant, as that scheme closed in April 2022. Our guide to who qualifies for the EV chargepoint grant sets out each route. Grant claims must be made through an OZEV-authorised installer; tell us your situation at the quote stage.
The kit, and what to bring to the survey
The charger we fit is EnSmart’s SmartBee-M, a 7 kW smart unit. The battery systems in our own job photos are EnSmart; our battery storage page for Basingstoke covers those and how a system is specified. For the charger itself, our home EV charger guide covers speeds, connectors and the tethered or socketed choice.
At the survey, the useful facts are your annual electricity use from a bill, how many cars you run and when they are home, and whether panels are already on the roof or planned. Those, not the size of the car, decide the battery.
Sources: Energy Saving Trust, Battery storage (last updated 19 August 2026); Ofgem, Typical Domestic Consumption Values (from 1 July 2026); HMRC, VAT Notice 708/6; DfT and DVLA, VEH0142 licensed plug-in vehicles by local authority, private keepers, end of June 2026 and June 2025 (published 23 September 2026); ONS Census 2021, TS045 Car or van availability, via Nomis (read 19 October 2026); European Commission JRC, PVGIS 5.3 (PVGIS-SARAH3, 2005–2023), 4 kWp, 35°, due south, 14% losses, run 15 October 2026; NESO GB DNO licence areas (May 2024) and SSEN, Who we are; Energy Networks Association, EREC G98 Issue 2 (10 March 2025); Electric Vehicles (Smart Charge Points) Regulations 2021; GOV.UK, Changes to electric vehicle chargepoint grant schemes from 1 April 2026 (updated 7 July 2026).