Calculate the solar panels, battery bank, inverter, and charger you need to charge your electric vehicle from the sun.
Supports Level 1 & Level 2 charging with a "Direct Solar" budget mode — no batteries needed.
Charging your electric vehicle with solar panels is one of the most cost-effective ways to "fuel" your car. A typical EV uses 0.25–0.35 kWh per mile (EPA rated). For a 30-mile daily commute, that's only about 7.5–10 kWh per day — easily covered by a modest solar array.
Solar charges a battery bank during the day. The inverter draws from batteries to power your EV charger any time — day or night, rain or shine.
The EV charger connects to the inverter as a regular AC load. The inverter is powered directly by solar panels — no battery bank needed. Charging only happens during solar production hours.
| Level | Voltage | Typical Amps | Power | Miles/Hour | Full Charge Time* |
|---|---|---|---|---|---|
| Level 1 | 120V | 12A | 1.4 kW | 3–5 | 40–60 hours |
| Level 2 | 240V | 32–48A | 7.7–11.5 kW | 25–35 | 6–10 hours |
Per the National Electrical Code (NEC 625.40), EV chargers are classified as a continuous load — the circuit breaker must be rated at 125% of the charger's max amperage:
| Charger Amps | Breaker Size | Wire Gauge |
|---|---|---|
| 16A | 20A | 12 AWG |
| 24A | 30A | 10 AWG |
| 32A | 40A | 8 AWG |
| 40A | 50A | 6 AWG |
| 48A | 60A | 6 AWG |
One solar owner reported a single-day production of 36 kWh — enough to power their entire household, heat 210 liters (55 gallons) of water to 45°C, and charge two electric vehicles (a Nissan Leaf to 80% and a Tesla to 60%) — all from rooftop solar alone.
This demonstrates that a well-sized solar system can handle EV charging alongside normal household loads. A 6–8 kW solar array in a good-sun region can realistically produce 30–40 kWh on a clear day.
Our main calculator sizes your full solar + battery system including all household loads.
Full System CalculatorFor 30 miles of daily driving in a typical EV (~9 kWh/day), you need about 3 kW of solar (8–10 panels of 350–400 W). For 50 miles/day (~15 kWh), plan 5 kW. For 100 miles/day (~30 kWh), plan 10 kW. These numbers assume average US sun (4.5 PSH); in sunnier states like Arizona you can scale down ~20%, in cloudy states like Washington scale up ~30%.
A Tesla Model 3 or Model Y uses about 0.25–0.30 kWh per mile. For 30 miles/day, that’s 8–9 kWh/day — about 3 kW of solar. For 12,000 miles/year (~33 mi/day), plan ~3.5 kW solar dedicated to charging. Pair with a Powerwall to charge during the day from solar and discharge to the EV overnight via the wall connector.
Yes — chargers like the Wallbox Pulsar Plus, ChargePoint Home Flex, and Tesla Wall Connector can be configured to use only solar surplus (with a CT clamp on the grid feed). This avoids battery storage costs but only works during daylight. For nighttime charging from solar, you need battery storage (Powerwall or equivalent) to shift midday production to overnight.
Not strictly — if you can charge mid-day when the sun shines (work-from-home setup, or your EV is parked at home all day), direct solar charging works without batteries. If you charge mostly overnight or during cloudy days, you need either grid backup (net metering) or battery storage to use stored solar energy.
Once your solar system is paid off, EV charging is essentially free. A 3 kW dedicated solar setup costs roughly $7,000–$10,000 installed (before any local incentives). Spread over 25 years of panel life, that’s $0.06–$0.08 per kWh — a fraction of public DC fast charging ($0.40–$0.55/kWh) and cheaper than residential grid power in most states.
Level 2 (240V, 16–48 A) is the practical choice for solar EV charging because it can absorb 4–11 kW of real-time solar production. Level 1 (120V, 12 A) only takes 1.4 kW, which means a 3+ kW solar array would have to dump excess to the grid or curtail output. For dedicated solar charging, Level 2 with smart load matching is the standard.