Charging an EV From Solar: What You Save
Charging an EV from your own solar panels sounds like free fuel, and in a narrow sense it is, but most UK drivers won’t be able to do most of their charging that way. Here’s why, and what the savings actually look like once you account for it.
Why most solar-charged miles aren’t really solar-charged
EVs are usually charged overnight, when solar panels aren’t generating anything. Unless you’re specifically home during the day and set your car to charge then, or you have a battery and a smart charger that shifts generation into the evening, most of your charging will still come from the grid, just at whatever rate your tariff gives you overnight.
Where solar genuinely helps
- Daytime charging. If you work from home or charge during the day (weekends, retired households, second cars), solar can directly offset a real share of charging costs.
- Smart/solar-diverting chargers. Some EV chargers can automatically direct surplus solar generation to the car rather than exporting it, topping up “for free” whenever there’s spare generation.
- Combined with a battery. Stored solar can be released to charge the car in the evening instead of drawing from the grid.
The bigger saving is the tariff, not the panels
Even without solar, home charging is dramatically cheaper than public charging:
| Where you charge | Typical cost per mile |
|---|---|
| Public rapid charger | 17p to 26p |
| Home, standard tariff | 7p to 8p |
| Home, overnight EV tariff (e.g. Octopus Go) | around 2p |
Switching from public charging to a cheap overnight home tariff saves most of the money. Solar generation on top of that captures whatever slice of your charging happens to fall during daylight hours.
The bottom line
Don’t buy an EV charger expecting your solar panels to fuel it for free, most of your mileage will still be grid-charged overnight. What solar plus a smart charger does is shave a genuine chunk off an already-cheap home charging bill. See our full EV charger cost and savings guide for installation pricing. Get matched with installers for solar, an EV charger, or both.
Prefer a phone call? Also £250 off your purchase!
Our affiliate partner Blue Ape Renewables install solar, batteries, heat pumps and EV chargers across the UK and are rated 5 stars on Trustpilot. Book a call within as little as 15 mins.
09:00 - 17:15 Mon - Sat.
Affiliate link - we earn a commission if the quote leads to a sale, and you get £250 off your purchase.
Frequently asked questions
Can I charge my EV for free from solar panels?
Not usually. EVs are typically charged overnight when solar isn't generating, so most charging still comes from the grid unless you specifically charge during the day or have a battery and smart charger that shifts generation into the evening.
How much cheaper is home EV charging than public charging?
Home charging on a standard tariff runs about 7p to 8p per mile versus 17p to 26p per mile on a public rapid charger, and an overnight EV tariff like Octopus Go can bring that down to around 2p per mile.
Does solar make a real difference to EV charging costs?
It helps if you charge during the day, use a smart charger that diverts surplus generation to the car, or pair it with a battery, but for most drivers the bigger saving comes from switching to a cheap overnight home tariff rather than from the panels themselves.