EV + Solar Panels Savings Calculator
See how much you save by charging your EV at home — and how much extra you save when solar panels power that charging. Stacks fuel savings, home charging costs, and solar contribution side by side.
Quick-fill: select your EV
Full Savings Breakdown
Cumulative Savings vs a Petrol Car
| Period | EV saving (no solar) | Solar bonus | Total saving |
|---|
EV charged on UK grid. CO₂ saving increases further as the grid decarbonises.
🇬🇧 Could you get solar for free?
UK homeowners on certain benefits may qualify for free solar panels through ECO4 or the Warm Homes Plan — dramatically reducing the investment needed to power your EV with solar.
Check UK grant eligibility →Frequently Asked Questions
How much can I save charging my EV with solar panels?
A typical UK EV owner driving 8,000 miles/year and charging 80% at home spends around £550/year on home electricity for charging. If solar panels cover 40% of that home charging (achievable if you charge during the day or add a battery), the saving is around £215/year on top of your normal solar savings. Combined with the fuel cost saving versus a petrol car, the total annual financial benefit of an EV + solar setup is typically £1,200–£2,500/year.
Do I need a special charger to use solar to charge my EV?
For basic solar EV charging, you just need a home EV charger (Level 2, 7kW is standard) and a compatible inverter that allows export control. To maximise solar self-consumption for EV charging, a "solar-optimised" EV charger (like Zappi by myenergi, or Hypervolt with solar integration) automatically detects surplus solar generation and boosts charging speed when your panels are producing excess. These chargers cost £500–£800 more than standard units but can significantly increase the proportion of solar you use for charging.
What % of EV charging can realistically come from solar?
Without a smart charger or battery: if you typically return home and plug in during daylight hours and your solar is still generating, 20–35% of charging might come from solar. With a solar-optimised charger (like Zappi): 35–60% if you leave the car plugged in during the day. With a home battery that stores midday solar for evening charging: 50–70%. The exact figure depends heavily on your lifestyle, car size, and solar system output.
Is an EV cheaper to run than a petrol car even without solar?
Yes, significantly. A petrol car doing 8,000 miles/year at 40 MPG costs around £1,390/year in fuel (at 145p/litre). The same mileage in an EV at 3.5 miles/kWh costs £560/year in home electricity at 24.5p/kWh — a saving of £830/year before any solar contribution. With solar covering 40% of charging, annual EV charging cost drops to ~£340, pushing total savings over £1,000/year versus petrol.
Does my EV qualify for any UK grants alongside solar grants?
The UK's EV grant for private buyers ended in June 2022. However, the OZEV (Office for Zero Emission Vehicles) still offers: (1) EV chargepoint grant — up to £350 off a home EV charger installation for eligible homeowners. (2) Workplace Charging Scheme — for employers installing chargers. (3) EV infrastructure grants for housing providers. Additionally, some energy suppliers (like Octopus Intelligent) offer free or subsidised EV charger installation when you join their tariff.
Which EVs are most efficient for solar charging?
Efficiency (miles/kWh) determines how much you get from each kWh of solar electricity used. The most efficient include: Hyundai IONIQ 6 (4.3 miles/kWh), Tesla Model 3 LR (4.0), Kia EV6 (3.8), Volkswagen ID.3 (3.6), Nissan Leaf (3.6), BMW i4 (3.4), and Volkswagen ID.4 (3.5). Real-world efficiency varies with speed, temperature, and driving style — cold weather reduces efficiency by 15–25%.
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