How to Charge Your EV Using Solar Energy
- Ben Henderson
- Oct 13
- 5 min read
For many UK homeowners, the dream of owning an electric vehicle (EV) is about more than just lower running costs. It’s about sustainability — the idea of fuelling your daily journeys with clean, renewable energy that you generate yourself. Solar panels make that dream a reality.
But how does it work in practice? How do you size a system, choose the right charger, and make sure you’re not just charging your car, but charging it intelligently? This guide walks you through everything you need to know about EV charging with solar in 2025 — from rooftop panels to driveway charging.
Why Solar + EV is the Perfect Match
An EV is essentially a large, mobile battery. A solar array is a clean, steady generator. Pairing the two means:
Lower running costs: Every mile charged on sunshine avoids expensive peak-rate electricity.
Greener journeys: True zero-emissions driving, powered by your own renewable energy.
Energy independence: Less reliance on grid price spikes or outages.
Smarter homes: Solar and EV charging can be orchestrated to work with batteries, tariffs, and smart devices.
It’s not just about saving money — it’s about creating a lifestyle where energy works for you.
Step 1: Get the Right Solar Setup
Not every solar system is equal when it comes to EV charging. Here’s what to look for:
Panel choice: High-efficiency modules like AIKO Neostar N-Type panels give more usable power from limited roof space.
Orientation and tilt: Panels should be modelled for year-round performance, not just midsummer peak.
Mounting and detailing: Quality mounting systems (Van der Valk, for example) ensure stability and durability — because you’ll need reliable generation for decades.
Shading management: Optimisers such as Tigo prevent one shaded panel from dragging down the whole system.
Think of this stage as building the foundation. Without steady generation, EV charging from solar can feel unpredictable.
Step 2: Add a Home Battery for Flexibility
Here’s the big question homeowners ask: “Do I need a battery to charge my car from solar?”
Technically, no. You can plug in an EV charger that simply follows the sun, charging when panels are producing. But in practice, a home battery makes the system far more flexible.
Take the Sigenergy SigenStor, for example:
Stores solar generation during the day for evening EV charging.
Switches to backup mode during outages — keeping car charging available.
Scales modularly, so more storage can be added if you get a second EV.
Works with dynamic tariffs to decide whether to charge from the grid at cheap rates or wait for sunshine.
Without storage, your car has to be home and plugged in during sunny hours to benefit fully. With storage, you can generate at midday and still charge at 10pm.
Step 3: Choose a Smart EV Charger
The final piece of the puzzle is the EV charger itself. In 2025, UK homeowners have some excellent choices — including the Simpson & Partners range, known for its combination of style, durability, and solar integration.
A smart charger should:
Work with solar: Follow real-time surplus generation, pausing and resuming to match available power.
Offer tariff scheduling: Charge overnight at off-peak rates when solar isn’t available.
Balance loads: Prevent tripping the main fuse by monitoring total household demand.
Integrate with apps: Give you visibility over how much of your charging is solar vs grid.
The best setups allow you to blend sources. For example, 70% solar + 30% cheap night rate, automatically. That way, you never waste sunshine but also never start the morning with an empty car.
A Day in the Life of Solar EV Charging
Morning: Panels begin covering household baseload. If the car is plugged in, the charger may trickle in early energy.
Midday: Surplus generation rises. The battery tops up first, then the EV charger activates, feeding clean power into the car. Optimisers make sure shading doesn’t spoil the output.
Evening: The family arrives home. Even without sunshine, the car can be charged from stored solar in the SigenStor. The charger blends stored energy with off-peak grid if needed.
Overnight: Tariff optimisation kicks in. If tomorrow looks cloudy, the system can top up from the grid at cheap rates. If it’s forecast to be sunny, it waits, leaving the panels to do the heavy lifting tomorrow.
How Many Panels Do You Need to Charge an EV?
This is where numbers matter. A typical EV consumes around 3–4 miles per kWh.
8 high-performance panels (~3.6kWp system) can generate around 3,000 kWh per year in UK conditions. That’s up to 10,000 solar miles annually. 16 panels (~7.2kWp system) can double that — covering most drivers’ yearly mileage entirely from sunshine.
Of course, actual figures depend on driving habits, location, and whether you store energy in a battery. But even smaller arrays can make a meaningful dent in charging costs.
Smart Tariffs: The Secret Weapon
Solar alone is powerful. Solar + storage is smarter. But solar + storage + dynamic tariffs is where the real optimisation happens.
In 2025, more suppliers are offering tariffs that flex by the half-hour. Your system can automatically:
Export when prices spike.
Charge your EV (or battery) when prices dip.
Always prioritise self-consumption for the cleanest, cheapest energy.
This turns your EV and home battery into active players in the energy market — saving you money while reducing strain on the grid.
Common Mistakes to Avoid
Undersizing the system: A few panels might cover lighting, but not meaningful EV miles. Model properly for your lifestyle.
Forgetting about shading: Even partial shade can kill EV charging plans. Use optimisers.
Buying a “dumb” charger: Without solar or tariff integration, you’ll miss most of the value.
Skipping storage: If you’re rarely home midday, no battery = missed solar miles.
Messy installation: Poor cable runs or cheap hardware shorten system life and add headaches later.
Results You Can Expect
With the right setup, homeowners can look forward to:
Cheaper driving — potentially pennies per mile when charging on solar.
Lower bills overall, with excess solar supporting the whole home.
Resilience during power cuts, with critical loads and EV charging maintained.
Cleaner journeys, cutting tailpipe and upstream emissions together.
Future-ready flexibility for a second EV, a heat pump, or dynamic tariff participation.
The Road Ahead
In 2025, solar-powered EV charging is no longer niche — it’s the natural next step for sustainable homeowners. By combining efficient panels, a modular battery like SigenStor, and a smart charger such as Simpson & Partners, your home becomes a true energy ecosystem.
The driveway isn’t just where the car sits. It’s where the sun meets the street.
Thinking about powering your EV from solar? Speak to Now EV today to design a system that’s tailored to your driving, your home, and your future!
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