Solar Panels & EV Charging: How to Set Up Your Dorset Home

If you’re thinking about combining solar panels and EV charging at your Dorset home, you’re not alone. Electric car ownership in the UK is growing fast — nearly one in four new cars sold in 2025 was fully electric, according to the SMMT, with over 473,000 battery electric vehicles registered that year alone. For Dorset homeowners who already have solar panels, or are thinking about getting them, pairing that system with an EV charger is one of the most practical and cost-effective things you can do. Done well, you’re essentially running your car on sunshine — and it costs very little per mile.

In Brief

Charging an EV from solar requires a smart solar-compatible charger, such as a Zappi, since a standard charger simply draws from the grid regardless of how much surplus solar is available. Dorset homeowners charging mainly from solar can bring typical annual charging costs down from around £645 to under £150, a saving of roughly £500 a year compared with grid-only charging.

Here’s everything you need to know about setting up solar panels and EV charging at your home in Dorset.

 

Can You Charge an EV Directly From Solar Panels?

Yes, you can. But it helps to understand how the energy actually flows before you set expectations.

Your solar panels generate electricity during daylight hours. That electricity powers your home first, and anything left over (the surplus) either gets exported to the grid or, with the right setup, diverted into your car. The key word there is surplus. If your household is using most of what the panels generate, there may not be much left to charge the car.

That said, for many Dorset homeowners the maths works well, particularly if:

• Someone is at home during the day and the car is parked up
• You have a larger solar array (10 panels or more)
• Your daily mileage is modest — most people drive between 20 and 40 miles a day

One thing worth keeping in mind is the Smart Export Guarantee (SEG). If you’re exporting surplus solar to the grid, you’ll typically receive around 4 to 15p per kWh depending on your tariff. Grid electricity, on the other hand, costs around 24p per kWh. Charging your car with surplus solar instead of exporting it is worth considerably more per unit — so using that energy in your car rather than sending it back to the grid is nearly always the better financial decision.

Do You Need a Special EV Charger for Solar?

This is where a lot of people go wrong. A standard EV charger — or even a three-pin plug — will charge your car, but it has no way of knowing where the electricity is coming from. It’ll just draw from the grid as normal, regardless of how much solar your panels are generating at that moment.

To actually use your surplus solar to charge your car, you need a smart solar-compatible wallbox. These chargers communicate with your inverter in real time, monitoring how much surplus is being generated and adjusting the charge rate accordingly.

The most widely used solar-compatible charger in the UK is the Zappi by myenergi, which is manufactured in the UK and has become something of a go-to recommendation for homes with solar. It operates in three modes:

• ECO+ mode — charges your car using surplus solar only. If cloud cover reduces generation below a minimum threshold, charging pauses until the sun returns. You’re genuinely only charging with free energy.
• ECO mode — uses surplus solar where available, but tops up from the grid if needed. Useful when you need a guaranteed charge by a certain time.
• FAST mode — charges at full speed (7kW single phase) from the grid, like a conventional charger.

The Zappi is compatible with the Intelligent Octopus Go tariff and similar smart tariffs, which means you can also schedule overnight charging at off-peak rates when the car needs more charge than the solar has provided during the day.

Other good solar-compatible options include the Ohme Home Pro and the Hypervolt Home 3 Pro, though the Zappi remains the most popular choice for solar households.

Do You Need a Battery to Charge Your EV at Night?

This is probably the question we get asked most often, and the honest answer is: it depends on how you use your car.

Without a home battery, your solar panels charge the car during the day (when the sun is out) and you draw from the grid at night. For most households, this is perfectly workable — particularly if the car is parked at home during daylight hours.

With a home battery, surplus solar generated during the day is stored and can be used to charge the car in the evening or overnight. This reduces your grid dependency further and makes the whole system more self-sufficient.

However, there are realistic expectations to set here:

• A typical home battery stores between 5 and 13.5 kWh
• The average EV uses around 3 to 4 miles per kWh of charge
• So a full home battery might add between 15 and 50 miles of range to your car overnight

For a homeowner driving 25 to 30 miles a day, that’s often enough. For heavier EV users, or anyone who wants to fully charge from zero, a battery alone won’t cover it — you’ll still need some grid top-up.

A practical middle ground for many Dorset households is combining solar panels and a Zappi charger with a smart tariff like Intelligent Octopus Go, which offers very cheap overnight rates (sometimes as low as 7p/kWh). You charge from solar during the day and from cheap overnight electricity when needed. The battery storage then becomes optional rather than essential for most people.

What Size Solar System Do You Need for EV Charging?

The size of the system you need depends on your total electricity usage — not just the car. It’s a mistake to design a solar system purely around EV charging without factoring in your household consumption at the same time.

That said, here are some useful rules of thumb:

• The average UK EV driver covers around 7,500 miles per year
• At roughly 3.5 miles per kWh, that works out to around 2,150 kWh per year just for the car
• A 4kW solar array in Dorset generates roughly 3,500 to 4,000 kWh annually, depending on roof orientation and shading
• According to Joju Solar, a 4kW roof could power a typical EV for around 20,000 miles per year over the system’s lifetime

For a household that wants solar to cover both the home and the car comfortably, a system of 10 to 14 panels (roughly 4 to 5kW) is a sensible starting point. If you have two EVs, or higher than average mileage, that number goes up accordingly.

The critical thing is to get a proper system design rather than a one-size-fits-all quote. A good solar panel installer in Dorset will calculate your actual consumption, assess your roof’s orientation, check for shading, and design a system around your real-world needs — including EV charging.

Is It Actually Worth It? The Numbers for Dorset Homeowners

Let’s put some rough figures on this.

Charging a typical EV from the grid in Dorset at the current average rate of around 24p per kWh costs approximately £645 per year for 7,500 miles of driving.

Charging the same car primarily from surplus solar brings that cost close to zero for the solar-generated portion. Even accounting for days when the sun doesn’t cooperate and you need some grid top-up, many solar EV owners report annual charging costs of under £150 per year.

That’s a saving of roughly £500 per year on fuel alone, on top of whatever the solar system is already saving on household electricity bills. Over the typical 25 to 30 year lifespan of a solar panel system, the cumulative savings from EV charging alone are significant.

There’s also the environmental angle. Combining solar panels with an EV is one of the most impactful steps a Dorset homeowner can take to reduce their carbon footprint — you’re running a zero-emission vehicle on zero-emission electricity. According to the RAC, the average range of a new electric car is now around 300 miles, making range anxiety much less of a concern than it once was — and a home solar setup means you’re starting each day with a full, free charge.

What Does the Setup Process Look Like in Dorset?

Getting solar panels and EV charging set up together is simpler than most people expect, and doing both at the same time makes sense — there’s less disruption, and the system can be designed and commissioned as a whole.

Here’s what the process typically looks like when you work with Ace Energy:

1. Free survey — we visit your property, assess your roof, check orientation and shading, look at your electricity usage and discuss your EV charging needs
2. System design — we recommend the right number of panels, inverter, and whether battery storage makes sense for your situation
3. Installation — panels, inverter, and Zappi charger are all installed in a single visit in most cases
4. Commissioning and setup — we configure the Zappi to work with your solar system, set up the myenergi app, and walk you through how to get the most from the system
5. MCS certification — as MCS-certified installers, we handle all the paperwork for your Smart Export Guarantee registration

We cover all of Dorset including Bournemouth, Poole, Dorchester, Weymouth, Wimborne, Blandford Forum, Shaftesbury and surrounding areas. If you’re in a rural part of Dorset and not on the mains gas network, combining solar with an air source heat pump and EV charging can cover almost all of your home’s energy needs from renewable sources — something worth discussing during your survey.

Frequently Asked Questions

 

If you’d like to talk through solar panels and EV charging for your Dorset home, get in touch with the team at Ace Energy for a free, no-obligation survey. We’ll take a look at your property and give you a clear picture of what’s possible and what it would cost.