How many solar panels do you need to charge an electric car?

Imagine having a fully fueled car... without ever having to pay for fuel. It’s not a pipe dream—it’s completely possible with solar panels and an electric vehicle. No trips to the gas station, no fluctuating fuel or electricity prices, just clean energy flowing from your solar panels to your car.

Electric vehicles (EVs) and solar panels are an increasingly popular dynamic duo that puts money back in your pocket and lessens fossil fuel emissions. With both technologies becoming more affordable, you might wonder how many solar panels you need to charge your EV.

The quick answer is it usually takes 5-14 solar panels to charge an EV. But it depends on the make and model of your vehicle, the weather, and your driving habits. Here's a quick breakdown to help determine how many solar panels you need to power your EV reliably.

First, think about how you use your EV and how much electricity it takes to support it. You can look at it in two ways: how much power it needs for a full charge and how much it uses per mile, usually measured in kilowatt-hours per 100 miles (kWh/100 mi).

Your EV’s battery size tells you roughly how much electricity it takes to “fill the tank.” Most EV batteries hold between 25 and 100+ kWh, which is pretty large. For comparison, the Tesla Powerwall 3, the most popular home battery on EnergySage, stores 13.5 kWh of electricity.

Battery size and range of popular EVs

Ranges and efficiency ratings are EPA estimates from fueleconomy.gov for 2026 models, except the Ford F-150 Lightning and Hyundai Ioniq 6 Standard, whose latest ratings are for 2025.

That depends on how far you tend to drive. Your needs will be different if you live in an urban area and don’t drive much versus having a long commute every day.

The average American drives about 13,735 miles per year, according to federal data. At that amount, most EVs will need around 3,400 to 6,700 kWh of electricity per year.

Annual electricity usage of popular EV models

*Based on 13,735 miles of driving per year.

How to find your EV's electricity use

Averages are a good starting point, but your own car and commute are what count. The easiest place to find your EV’s efficiency is the window sticker on a new car, which lists a combined rating in kWh per 100 miles. If you don't have a sticker, you can look up your make, model, and year on fueleconomy.gov.

That rating already includes the electricity lost while charging, because the EPA measures EV efficiency at the wall outlet instead of at the battery. That makes it the right number for sizing solar: your panels need to cover what your car pulls from the wall, not just what ends up in the battery.

Once you have your rating, use this formula:

Yearly electricity use (kWh) = yearly miles × kWh per 100 miles ÷ 100

For example, if you drive 13,735 miles a year in a car rated at 30 kWh/100 mi, you’ll use about 4,121 kWh a year (13,735 × 30 ÷ 100).

A few tips to sharpen your estimate:

• Use your real mileage. Your odometer, service records, or annual inspection paperwork will tell you how far you actually drive in a year.

• If you’re using your car’s own efficiency readout instead of the EPA rating, it may not count charging losses. Add about 10%, the typical charging loss for combined city and highway driving.

• Plan for winter. EVs heat the cabin with battery power, so expect higher electricity use in cold months if you live somewhere with real winters.

To calculate the number of solar panels required to power your EV, you'll need to know three things: 

1. How much electricity your car uses annually 

2. The total wattage of the solar panels you plan to install 

3. The production ratio of your panels, or how well solar panels produce electricity where you live

Once you understand these numbers, you can plug them into the following equation:

Number of panels = annual electricity usage/production ratio/panel wattage

Let's do the math for the average American driver:

• A typical EV requires about 3,000 to 6,700 kWh of electricity per year.

• According to the most recent EnergySage Intel Report, 430 to 460-watt panels are the most frequently quoted solar panels on EnergySage. We'll use 450 W panels for this example.

• Production ratios in the U.S. are typically between 1.1 and 1.6, depending on the region; solar panels tend to produce more electricity in sunnier climates.

Number of panels = 3,000-6,700 kWh / 1.1-1.6 / 450 W

Based on this example, charging an electric vehicle will typically require 5-14 solar panels. We round up to the next whole panel, since you can't install part of one. Very efficient cars, short commutes and consistent sunny weather can land you at the low end, while larger electric trucks, long commutes and less sunshine can push you toward the top.

Let's say for example you drive a Ford F-150 Lightning XLT in Massachusetts and you want to buy 450 watt panels.

• Annually electricity usage: 6,730 kWh a year

• Production ratio: 1.1

• Panel wattage: 450

6,730 / 1.1 / 450 = 13.6 panels, which rounds up to 14.

For the table below, we used a production ratio of 1.1 for Massachusetts and 1.5 for California.

Number of solar panels required to charge popular EVs

Solar-powered EV charging can eliminate your home charging costs entirely, putting more than $700 a year back in your pocket. Here’s how average annual fueling costs compare for a driver covering 13,735 miles per year:

Prices and efficiency assumptions come from Qmerit’s 2026 analysis: an EV using about 28.6 kWh per 100 miles and a gas car getting about 25 mpg.

Over 25 years, charging an EV with solar can save drivers more than $17,500 compared to charging at home without solar. Compared to gas, the savings land between about $41,000 and $59,000, depending on whether gas prices fall back to early-2026 levels or stay near where they are today.

One note: These estimates hold today’s prices flat and don’t subtract the cost of the extra panels: at the U.S. average of $2.60 per watt on the EnergySage Marketplace, the eight 450 W panels this EV would need in Massachusetts cost roughly $9,400 before incentives. That’s why the payoff grows the longer you own your system.

Plus, solar offers price stability. While residential electricity prices have risen about 4.8% annually and gas prices swing with world events, solar owners lock in steady, predictable energy costs for decades.

Charging your EV with solar shrinks your carbon footprint

Charging your EV with solar energy vs. grid electricity is better for the planet. Much of the U.S. power grid still relies on fossil fuels. Using clean, renewable energy from your home solar panels cuts your carbon footprint, reduces your demand on utilities, and helps improve air quality.

The beauty of pairing solar with an EV is that both technologies get better together. Your panels charge your car and change the economics of driving electric at the same time. Charging an EV from the grid already costs less than filling up a gas tank, but when you generate that electricity yourself, you’re driving on sunshine. Once you break even on your solar panel system, every mile is free.

You don’t need to cover every mile you drive with solar. Even if your panels only offset 70% of your EV’s charging needs, you’re still dramatically cutting both your costs and carbon footprint compared to any gas-powered alternative. The key is sizing your system correctly from the start.

If you’re already considering solar, now’s the time to factor in EV charging—even if you haven’t bought the car yet. It’s far easier (and cheaper) to install enough capacity upfront than to expand your system later.

When you compare quotes on the EnergySage Marketplace, let installers know which EV you drive (or plan to buy) and roughly how many miles you cover in a year. They’ll size your system to match, and your Energy Advisor can help you check the math.