How many solar panels does your EV need?
Pick your car, your state and how far you drive. We'll show the panels, the cost and how fast they pay for themselves, using EPA, EIA and PVWatts data.
Battery 75 kWh · Efficiency 3.45 mi/kWh · Range 310 mi
Sun 6.08 hrs/day · Power $0.34/kWh · Gas $6.03/gal
Some charging by day, some at night.
System size 2.4 kW · your car uses about 3,703 kWh a year
About 8% of a typical roof · charging about 1.1 hrs/day
2.4 kW × $3.00 per watt · no federal tax credit (ended 2025)
5.7 years vs charging from the grid
Your car needs about 10.14 kWh a day. Compared with a similar gas SUV, you avoid about $2,853 of gas a year and 9,274 lb of tailpipe CO₂. Over 20 years (gas prices rising 3% a year), that's about $69,463 saved after paying for the panels.
Prices used for California: electricity $0.34/kWh (EIA average, July 2026) · gasoline $6.03/gal. Gas prices: EIA weekly retail averages, week of Oct 19, 2026 (regions without their own EIA series follow the national trend). How this calculator works
What you'd spend a year to drive 12,775 miles
Fuel or electricity only, in California
Your panels make power during the day. To charge at night from your own solar, you'd need about 7 kWh of home battery (a Tesla Powerwall 3 holds 13.5 kWh). If your utility offers 1:1 net metering, the grid can do this job instead. Do you need a battery?
Solar checklist
5 / 5 passed- Fits on your roof123 sq ft
123 of about 1,500 sq ft on a typical roof (450 or less passes)
- Enough sunshine6.08 hrs
California: 6.08 hours of full sun a day (3.5 or more passes)
- Efficient car3.45 mi/kWh
Tesla Model Y Long Range AWD: 3.45 miles per kWh (3.0 or more passes)
- Pays back within 10 years5.7 yrs
Panel cost ÷ the grid charging you avoid each year (vs a gas car: 2.5 yrs)
- Home battery for night charging7 kWh
About 7 kWh of battery storage is suggested for night charging, unless your utility offers 1:1 net metering (then the grid works like your battery).
- Federal solar tax creditEnded 2025
The 30% credit ended for systems installed after Dec 31, 2025. Check state and utility rebates at dsireusa.org.
- Cuts tailpipe CO₂9,274 lb
CO₂ avoided each year vs a similar gas vehicle (27 MPG); 2,000 lb or more passes
Notes marked don't count toward the score.
Panels and savings at other daily distances
Tesla Model Y Long Range AWD in California
| Miles a day | kWh a day | Panels | Roof space | Gas saved a year | Payback vs gas | 20-year savings |
|---|---|---|---|---|---|---|
| 15 mi | 4.35 | 3 (1.2 kW) | 62 sq ft | $1,223 | 2.9 yrs | $29,256 |
| 25 mi | 7.25 | 4 (1.6 kW) | 82 sq ft | $2,038 | 2.4 yrs | $49,960 |
| 35 miYour choice | 10.14 | 6 (2.4 kW) | 123 sq ft | $2,853 | 2.5 yrs | $69,463 |
| 50 mi | 14.49 | 8 (3.2 kW) | 164 sq ft | $4,076 | 2.4 yrs | $99,919 |
| 75 mi | 21.74 | 11 (4.4 kW) | 226 sq ft | $6,114 | 2.2 yrs | $151,079 |
| 100 mi | 28.99 | 15 (6 kW) | 308 sq ft | $8,152 | 2.2 yrs | $201,038 |
Each car's efficiency comes from its official EPA rating, which already includes charging losses.
Average peak sun hours for each state from PVWatts v8 data (April 2026), with an 18% allowance for system losses.
Electricity prices from the EIA (July 2026), gas prices updated weekly from the EIA and AAA, and $3.00 per watt for installed solar (EnergySage and SolarReviews, 2026). How this calculator works
Solar panel needs for popular EVs
Panel counts for a 35-mile day with average US sunshine. Open any car for its full solar report.
Model Y Long Range AWD
Model 3 Highland RWD
F-150 Lightning (Extended Range 131 kWh)
Ioniq 5 AWD Long Range
EV6 Wind / GT-Line RWD
Equinox EV LT / RS (FWD)
R1T Dual-Motor (Large Pack 135 kWh)
i4 eDrive40 Gran Coupe
Featured guides
Plain-English guides to charging your EV with solar, checked against our calculator.
The Complete Guide to Solar EV Charging (Daytime, Net Metering or Battery)
How charging an EV with rooftop solar really works: how many panels a typical commute needs, the three ways to use your solar (daytime charging, net metering or a home battery), and how smart chargers match your car to your panels.
California NEM 3.0 and EV Charging: Do You Need a Battery?
Under California's Net Billing Tariff (NEM 3.0), exported solar earns only about 5 cents per kWh. What that means for charging an EV at night, when daytime charging or off-peak rates are enough, and when a home battery pays off.
Level 2 EV Charging Efficiency: How Much Power Is Lost, and Does It Change Your Solar Size?
Why your meter records more kWh than your car's battery receives, how Level 1, Level 2 and DC fast charging compare, and why EPA ratings already include these losses when you size solar.
How solar EV sizing works
Charging an electric vehicle directly from rooftop solar photovoltaic (PV) generation eliminates fuel expenses and insulates homeowners from volatile utility electric rates. However, designing a reliable off-grid or grid-tied solar EV system requires understanding electrical thermodynamics, inverter clipping, and regional solar insolation.
1. The Physics of Commute Energy Sizing
A vehicle's daily kilowatt-hour demand is calculated by dividing daily commute mileage by its EPA efficiency rating (mi/kWh). EPA ratings are measured at the wall outlet, so they already include charging losses and no extra factor is needed. For instance, driving 35 miles per day in a 3.5 mi/kWh vehicle requires about 10.0 kWh of electricity from the wall.
2. Allowing 18% for system losses
Solar panels are rated under laboratory Standard Test Conditions (STC) at 1,000 W/m² irradiance and 25°C cell temperature. In the real world, soiling, wiring losses, thermal coefficient degradation in hot summers, and DC-to-AC inverter conversion reduce actual harvest by approximately 18%. Our calculator multiplies output by 0.82 to allow for these losses, so its panel counts are slightly cautious. Shade and roof direction can still reduce your real output.
3. Battery Storage & Modern Net Metering (NEM 3.0)
In utility territories with net billing structures (such as California's NEM 3.0 or Arizona's RCP), surplus solar exported to the utility during midday is compensated at wholesale rates (~$0.05/kWh) rather than retail rates (~$0.35-$0.50/kWh). Pairing an EV charging system with a 10–13.5 kWh home battery storage unit enables complete solar self-consumption, preserving clean energy for overnight vehicle charging.
4. 25-Year Levelized Cost of Energy (LCOE)
Amortizing installation costs (about $3.00 per watt, with no federal tax credit for systems installed after 2025) over a standard 25-year panel warranty with a 0.5% annual degradation curve, residential rooftop solar delivers electricity at an effective cost of roughly $0.06 to $0.09 per kWh—about half the average US retail grid rate of about $0.18 per kWh.
Frequently Asked Questions
Common questions regarding solar sizing, home chargers, utility net metering, and federal tax credits:
Q1:How many solar panels does it take to charge an electric car?
For an average American daily commute of 35 miles, most electric vehicles need about 6 to 8 standard 400-watt solar panels (about 2.4 kW to 3.2 kW) with average US sunshine. Efficient sedans like the Tesla Model 3 need about 6 panels, while electric pickup trucks like the Ford F-150 Lightning need about 10 to 11 because they use more energy per mile. Sunnier states need fewer panels; cloudier states need more.
Q2:Can I charge my EV exclusively from rooftop solar without a battery?
Yes, provided the vehicle is plugged into a Level 2 home charger during daylight peak sun hours (typically 10:00 AM to 3:00 PM). If you commute to work during the day and must charge overnight, you either need a home battery storage system (such as Tesla Powerwall or Enphase IQ) or a utility that provides 1:1 Net Energy Metering (NEM) credits.
Q3:How much cheaper is solar EV charging compared to gasoline?
Over a 25-year lifespan, rooftop solar typically costs about $0.06 to $0.09 per kWh before any state or utility rebates, or roughly 2 to 3 cents per mile for most EVs. In comparison, gasoline at about $4.37/gallon (the US average in October 2026) in a 28 MPG car costs about 16 cents per mile. Depending on mileage and vehicle, charging with solar can save a typical driver about $1,300 to $2,000 a year in fuel.
Q4:Can I still get the 30% federal solar tax credit in 2026?
No. The Residential Clean Energy Credit (Section 25D) was ended by the July 2025 federal budget law for any system whose installation is completed after December 31, 2025. Systems finished by the end of 2025 can still be claimed on 2025 tax returns with IRS Form 5695. For new installations, look for state, local and utility rebates (searchable at dsireusa.org). Our calculator shows costs before any incentives.
Q5:What is the charging efficiency loss on home Level 2 chargers?
Residential AC Level 2 charging typically operates at 88% to 92% efficiency. Approximately 8% to 12% of electricity is lost due to thermal dissipation, alternating current to direct current (AC/DC) onboard rectification, and battery cooling circuits during charging. EPA efficiency ratings already include these losses, so our calculator does not subtract them a second time.
Q6:How does California NEM 3.0 affect solar EV charging?
Under Net Billing (NEM 3.0), exported solar earns only about 5 cents per kWh, about 75% less than before. The cheapest fixes cost nothing: charge while the sun shines if your car is home, or charge after midnight at off-peak rates instead of the 4–9 PM peak. A home battery (about $13,500 for a Powerwall 3) also works, but on car charging alone it takes about 20 years to pay back.