How Much of Your EV Charging Can Solar Actually Cover? It Depends on You.
Three variables — your mileage, your car, and your daily schedule — determine your real coverage. No rule of thumb gets this right. Our free calculator does.
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~90%Summer Solar CoverageA standard commuter with a correctly sized system can cover nearly all EV charging from solar during summer months.
100%Departure ReadinessThe optimizer guarantees your EV reaches the state of charge you need before every departure — solar never leaves you stranded.
20–30%Even in DecemberWinter solar is limited — but not zero. A correctly sized system still covers a meaningful share of EV charging in the darkest months.
6–8 kWpTypical System SizeFor a standard commuter driving 40 km/day with a compact EV. Larger cars or higher mileage need more — the calculator works it out for your exact situation.
"Up to 70% Solar Coverage" — But For Whom Exactly?
You've seen the claim. Solar can cover "up to 70%" of your EV charging. What the headline never says: that figure applies to a specific commuter, with a specific car, on a specific schedule, in a specific location.
For someone else — same solar system, different life — the real figure might be 30%. Generic percentages are not a starting point for a decision. They're a marketing average that tells you nothing about your situation.
The good news: finding your real number is not complicated. Three variables determine your coverage. Feed those into a system that knows your roof and your local weather, and you get a figure you can actually plan with. Below, we walk through exactly how each variable works.
Three Things Determine Your Coverage
Every solar EV calculation comes down to the same three inputs. Here's what each one does — and why the third one surprises most people.
1
Annual Mileage Sets Your Energy Demand
The more you drive, the more solar capacity you need to cover it — straightforward. A standard commuter driving 40 km/day needs roughly 7 kWh. A high-mileage driver covering 100 km/day needs 18 kWh. The gap is significant. Mileage sets the target your solar system needs to hit — the other two variables determine how well it hits it.
✓ 15–20 kWh per 100 km is typical
✓ Higher mileage = more solar generation needed
✓ Calculator uses your exact annual km
2
Your Car's Efficiency Changes the Equation
Not all EVs are equal. A compact electric uses around 13–15 kWh per 100 km; a larger SUV can exceed 25 kWh. The same solar system that covers 70% of a compact EV's needs might only cover 45% for the SUV — same roof, same schedule, very different result. Your car model is a direct input, not a footnote.
✓ Range: 13–25+ kWh/100 km across EV models
✓ Same solar system, different car = different coverage
✓ Real efficiency figures, not a generic average
3
Your Daily Schedule Opens or Closes the Solar Window
This is the variable most people don't think about — and the one that surprises them most. Solar peaks between 10am and 3pm. The window between when you return home and sunset defines how much of that energy is available to charge your car. An early bird who leaves at 5am but returns at 2:30pm catches the full afternoon peak — often achieving better coverage than a commuter who leaves at 8:30am but returns at 7pm. It's your return time, not your departure time, that matters.
✓ Return time matters more than departure time
✓ 2pm return = full afternoon solar peak captured
✓ Modelled hour-by-hour for your exact location
What the Numbers Actually Look Like
Three realistic driver profiles — see which one matches your situation.
Standard Commuter40 km/day · compact EV
charging from solarEV away — solar not captured
High Mileage100 km/day · mid-size EV
charging from solarEV away — solar not captured
Early Bird40 km/day · compact EV
charging from solarEV away — solar not captured
Get Your Number in 3 Steps
1
Map Your Roof & ConsumptionEnter your address and annual electricity consumption. PV Freund pulls your roof geometry and local solar irradiance from EU PVGIS satellite data automatically — no manual measurements needed.
2
Add Your EV Details & ScheduleEnter your vehicle model, annual mileage, and your typical departure and return times. The optimizer builds an hourly EV charging schedule around your solar window and ensures the car reaches the departure state of charge you need each morning.
3
See Your Solar Coverage & SavingsYour exact EV solar coverage %, recommended system size, annual savings, and payback. Home battery and V2H scenarios included where applicable.
Frequently Asked Questions about Solar EV Charging
Do I need a special wallbox for solar charging?
Not necessarily — any wallbox can charge from solar when the car is plugged in during solar peak hours. However, a solar-aware wallbox (one that adjusts charge rate based on available generation) squeezes more value from smaller surpluses and reduces the grid top-up. PV Freund's calculation assumes scheduled charging during peak hours, which works with any standard wallbox. Dynamic load management is an optional upgrade, not a requirement.
Can I charge my EV fully from solar alone?
For most households, the answer is: most of the year, partially — and in summer, yes for moderate daily mileage. A standard commuter driving 40 km/day needs roughly 7 kWh — output that a 6–8 kWp system can produce on many summer days. In winter, day length and irradiance drop sharply and the grid will top up the remainder. PV Freund shows you the honest monthly breakdown, not an annual average that hides the winter shortfall.
Do I need a home battery if I have an EV?
For EV charging specifically, no. Your EV's battery is already 4–8× the size of a typical home battery. The smart approach is to use the EV's storage directly — scheduling charging during solar peak hours — rather than routing energy through a separate home battery first. A home battery only makes sense if you want to shift solar energy to evening household loads (lights, appliances) beyond what the EV covers. PV Freund models both configurations and shows you which combination makes financial sense for your situation. If your EV supports V2H (Vehicle-to-Home bidirectional charging), the case for a separate home battery weakens further still — the car can discharge back into the home in the evening, covering appliances and lights from solar energy it stored during the day. PV Freund takes V2H into account when your vehicle supports it.
What if I have two EVs?
Two EVs double the daily energy demand, but they also give you more scheduling flexibility. If the two cars have different schedules — one returns early afternoon, one returns in the evening — the solar window can be split between them. PV Freund currently optimises for a single EV schedule; for two-EV households, run the calculation with combined mileage as a conservative estimate and note that actual coverage may be higher if the second car is home during peak solar hours.
Does it work in winter when there's less sun?
Yes, but with lower coverage. In central Europe, a correctly sized system can still cover 20–30% of EV charging energy in December–January. The annual average across all months — which is what PV Freund reports — is typically 50–70% for well-scheduled profiles. Winter doesn't eliminate the benefit; it just means a higher grid top-up for those months. The summer surplus partially offsets the winter shortfall in the annual calculation.
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