What Size Solar System Do I Need to Charge an Electric Car?
Six 2025 models, one example commute of 30 miles a day, and both sizing methods: a Phoenix year, and a 4- or 5-hour day with 14% default losses.
Full breakdown: what size solar system.
Whole-house context, if the car is only one line on the bill: how many solar panels and what size solar system for an average home.
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Six 2025 models at 30 miles a day
| Vehicle | kWh/100 mi (precise) | kWh/day at 30 mi | Phoenix kW | 4 PSH kW | 5 PSH kW | Source |
|---|---|---|---|---|---|---|
| Tesla Model 3 Long Range RWD | 25 (24.64) | 7.392 | 1.54 | 2.15 | 1.72 | fueleconomy.gov; yield PVWatts; losses PVWatts v5; hours Battle Born |
| Tesla Model Y Long Range AWD | 29 (28.79) | 8.637 | 1.80 | 2.51 | 2.01 | fueleconomy.gov; yield PVWatts; losses PVWatts v5; hours Battle Born |
| Nissan LEAF | 30 (30.43) | 9.129 | 1.90 | 2.65 | 2.12 | fueleconomy.gov; yield PVWatts; losses PVWatts v5; hours Battle Born |
| Chevrolet Equinox EV FWD | 31 (31.24) | 9.372 | 1.95 | 2.72 | 2.18 | fueleconomy.gov; yield PVWatts; losses PVWatts v5; hours Battle Born |
| Ford Mustang Mach-E RWD | 31 (31.44) | 9.432 | 1.96 | 2.74 | 2.19 | fueleconomy.gov; yield PVWatts; losses PVWatts v5; hours Battle Born |
| Ford F-150 Lightning 4WD extended range | 48 (47.91) | 14.373 | 2.99 | 4.18 | 3.34 | fueleconomy.gov; yield PVWatts; losses PVWatts v5; hours Battle Born |
Each fueleconomy.gov page lists a rounded kWh/100 mi and a finer combined figure in parentheses. Daily kWh uses the finer figure: precise × 30 ÷ 100. Phoenix kW = that daily total × 365 ÷ 1,755. Generic kW = (daily ÷ peak sun hours) ÷ (1 − 0.14). No extra charger-loss percentage is added; these sources do not publish one. The 14% is PVWatts array loss, already inside the generic column.
How to size it
The contrast the table is built for is the Model 3 against the F-150 Lightning. Same miles, very different electricity use. The other four vehicles sit between them, and the Equinox and Mach-E both display 31 kWh/100 mi while their precise figures differ (31.24 and 31.44).
- Model 3 daily energy: 24.64 × 30 ÷ 100 = 7.392 kWh. The page's rounded label is 25 kWh/100 mi; 25 × 30 ÷ 100 = 7.5 kWh, shown only so the rounded label can be checked. The array uses 7.392.
- Model 3 year: 7.392 × 365 = 2,698.08 kWh. Phoenix: 2,698.08 ÷ 1,755 = 1.54 kW. Generic: (7.392 ÷ 4) ÷ (1 − 0.14) = 2.15 kW, and at 5 hours 1.72 kW.
- Lightning daily energy: 47.91 × 30 ÷ 100 = 14.373 kWh. The rounded label is 48. Ratio of the precise figures: 47.91 ÷ 24.64 = 1.94, matching 14.373 ÷ 7.392.
- Lightning year: 14.373 × 365 = 5,246.145 kWh. Phoenix: 5,246.145 ÷ 1,755 = 2.99 kW. At 4 peak sun hours: 4.18 kW. At 5: 3.34 kW.
- Illustrative 400 W panels, rounded up from the unrounded watts: the Model 3 Phoenix result is 4 panels. The Lightning 4-hour generic result is 11 panels. 400 W is a divisor, not a vehicle charger rating.
Miles scale the day in a straight line because every column starts from kWh per 100 miles. Double the example to 60 miles and the daily kWh doubles; the kilowatts double with it. That is the same multiplication, not a new test. It still is not your driveway: the 1,755 yield is Phoenix (December plane-of-array 4.75, annual 6.54), and 4 to 5 peak sun hours is a baseline. Put the address into PVWatts and the household loads into the solar size calculator.
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FAQ
What size system covers a Model 3 at 30 miles a day?
24.64 kWh/100 mi × 30 ÷ 100 = 7.392 kWh/day. × 365 = 2,698.08 kWh, and ÷ 1,755 = 1.54 kW on the Phoenix run.
How does the F-150 Lightning compare?
47.91 ÷ 24.64 = 1.94 times the electricity use per mile. At the same example 30 miles, Phoenix is 2.99 kW for the Lightning and 1.54 kW for the Model 3.
What is the Lightning at 4 peak sun hours?
14.373 ÷ 4 ÷ (1 − 0.14) = 4.18 kW. At 5 peak sun hours it is 3.34 kW.
Are charging losses included on top?
The fueleconomy figures are combined electricity use in kWh per 100 miles. This page multiplies those by the example mileage. It does not add a separate charger loss, because that percentage is not in these sources. The 14% term is PVWatts' default array loss inside the generic kilowatt step.
Related questions
- What size solar system for an average home
- What size solar system for 30 kWh per day
- What size solar system for 1,000 kWh per month
All of these questions are listed on the topic map.
Sources
- fueleconomy.gov, 2025 Tesla Model 3 Long Range RWD — accessed Oct 2, 2026.
- fueleconomy.gov, 2025 Tesla Model Y Long Range AWD — accessed Oct 2, 2026.
- fueleconomy.gov, 2025 Nissan LEAF — accessed Oct 2, 2026.
- fueleconomy.gov, 2025 Chevrolet Equinox EV FWD — accessed Oct 2, 2026.
- fueleconomy.gov, 2025 Ford Mustang Mach-E RWD — accessed Oct 2, 2026.
- fueleconomy.gov, 2025 Ford F-150 Lightning 4WD extended range — accessed Oct 2, 2026.
- NREL/NLR PVWatts Version 8 API documentation — accessed Oct 2, 2026.
- PVWatts calculator — accessed Oct 2, 2026.
- NREL PVWatts Version 5 Manual, A. Dobos, September 4, 2014 — accessed Oct 2, 2026.
- Battle Born Batteries, How to Size Solar Panels for a Deep Cycle Battery System — accessed Oct 2, 2026.