EV Solar Charging Calculator

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.

Your EV & Driving Profile
US average commute: ~30 miles/day
Battery stores solar energy for overnight/cloudy-day charging.
How many days of EV charging without sun.

How Solar EV Charging Works

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.

Two Approaches: Battery Storage vs. Direct Solar
Battery Storage Mode

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.

  • Charge your EV overnight
  • Works during cloudy days (stored energy)
  • Higher upfront cost (batteries)
  • Best for: all-weather reliability
Direct Solar (Cheapest)

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.

  • 40–60% cheaper (no batteries)
  • Simplest wiring and maintenance
  • Charging limited to peak sun hours
  • Best for: daytime parking, budget builds

EV Charger Levels Explained

LevelVoltageTypical AmpsPowerMiles/HourFull Charge Time*
Level 1120V12A1.4 kW3–540–60 hours
Level 2240V32–48A7.7–11.5 kW25–356–10 hours
*Based on a 75 kWh battery from empty.

NEC Electrical Requirements

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 AmpsBreaker SizeWire Gauge
16A20A12 AWG
24A30A10 AWG
32A40A8 AWG
40A50A6 AWG
48A60A6 AWG
Real-World Solar EV Charging

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.

36 kWh
solar produced
2 EVs
charged
210L
hot water
100%
renewable

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.

Need a complete off-grid system?

Our main calculator sizes your full solar + battery system including all household loads.

Full System Calculator