Yes, if you don’t have an EV charging station, you can charge your electric car with solar panels. A small solar system will generally suffice if you are not looking to recharge the battery to maximum capacity.
But a considerably larger solar energy system will be needed if you plan on recharging the electric car to maximum capacity each time.
1️⃣ The average distance traveled and the car’s electricity use will determine how feasible it is to charge an electric vehicle with solar panels.
2️⃣ The size of the home solar system will determine the time taken to charge the car from empty to full in a reasonable time.
This article uses hypothetical scenarios to calculate the solar power required to charge several different EVs to provide sufficient charge for 50 miles per day.
How Many Solar Panels Are Necessary To Charge An Electric Car?
We need the following information to calculate how many panels will be required to charge an EV:
- The average daily mileage
- The EV range
- The EV battery size
- The number of peak solar hours per day.
Calculating The Number Of Solar Panels Needed
There are three steps in the calculation:
1️⃣ Calculate the energy use per mile (battery capacity/range (miles) = kWh per mile.
2️⃣ Calculate The Energy Consumed For The Daily Driving (multiply the daily distance (miles) by the kWh per mile = kWh per day.)
3️⃣ Calculate The Optimum Solar Panel System Size and divide the generated power required by the peak solar energy power available daily.
The list below details the results of the calculation across a broad range of electric vehicles.
When calculating the number of panels required, we have assumed a panel power capacity of 500 watts per panel.
There are two calculated columns, namely:
- The number of panels to top up the EV’s battery to provide charge for 50 miles (the average daily drive in America).
- The number of panels required to fully recharge the battery from zero to maximum capacity in one peak solar day.
A Tesla Model 3, Ford Mustang Mach E, and the VW ID would only require 4 panels to provide a daily charge equal to 50 miles of driving, whereas a GMC Hummer EV would need 13 panels for the same charge.
How Long To Charge An Electric Vehicle With A Solar Panel?
There are only a few hours each day when the sun produces maximum energy. This time frame is called peak sunlight (solar) hours.
The following list shows the number of days and hours it would take to recharge the same list of cars.
In this list, there are three calculated columns:
- The number of days a single 500-watt panel would take to charge the cars (to 100%)
- The number of hours (using calculated data from the list above) to charge to a 50-mile range.
- The number of panels needed for complete EV charging in one peak solar period of five hours.
Can A Portable Solar Panel Charge An Electric Car?
As seen from the above lists, a substantially sized solar system is needed to provide a meaningful charge to an EV.
It is, however, possible to use solar-recharged battery packs to provide an emergency top-up range charge to help get the car to the next recharge station.
Is A Regular EV Charger Compatible With Solar Panel Charging?
Yes, home charging stations such as the WallBox Pulsar Plus are compatible with home solar.
How an EV charger works on a solar system will depend on how the system is structured.
EV chargers are designed to accept an AC which they convert to either DC (or keep as AC) depending on the vehicle being recharged. An example of the variance is that Tesla uses DC batteries in the Model S and permanent-magnet direct current (DC) motors in the Model 3.
The solar panels would have to be connected to a suitably sized inverter (or series of inverters) to convert the DC from the panels into AC.
In a conventional MPPT inverter, a separate solar battery (or series of batteries) will be installed to store excess (unused) power from the panels.
The EV charger will be plugged into the inverter (more likely the wall plug if the system is integrated into the house) and draw charge from the system.
In an off-grid system, the power will be first drawn from the panels, and if the system requires an excess, it will be drawn from the battery.
In a grid-tied system, the power will be first drawn from the solar panels, and any excess amounts required will be pulled in from the grid.
The Benefits Of Charging Your EV With Solar Panels
The benefits of using solar panels are summarized below.
It Frees The User From State Provided Energy
Even with the high capital cost, the EV owner becomes energy independent from the electrical utilities and the constantly fluctuating gas prices.
It Is Considered A Green Energy Form
Although the initial manufacturing process and end-of-life disposal of solar systems are fraught with ecological problems, the energy produced is completely emissions-free.
The Federal And State Governments Promote Solar Installations
The schemes offered by each entity are as follows.
The Federal government has enacted legislation called the federal solar tax credit.
The government provides a 30% tax subsidy against the solar installation cost. The incentives provided by individual states do not affect the value of the federal government’s incentives.
The scheme will remain in place until 2035, with the benefits being slowly scaled back after 2033.
- 2033 – reduce to 26%.
- 2034 – reduce to 22%
- 2035 – the scheme will be shut down.
Individual States Assistance
Each state has an incentive scheme that operates separately and in addition to the Federal tax cut.
They range from one or a combination of the following:
- Qualifying residents receive an immediate rebate when they install a solar system.
- Some states offer a direct dollar-based tax reduction.
- Some allow the recipients (private and business) to claim a dollar value for each watt generated by the solar system.
- Many states zero rates the sales tax on solar system installations
- Most states allow solar system users to participate in net metering programs. Solar power producers can feed excess solar energy produced into the main system and receive credits on their utility bills.
- Maryland residents receive one Solar Renewable Energy Certificate (SREC) for each megawatt hour they generate. The SREC holder may then sell the certificate on the SREC market at the current values determined by the supply and demand.
You can charge your car using home solar panels and the associated system. It is economical to size the system to provide sufficient range for daily commuting (roughly 50 miles)
However, charging your EV from, say 20% to 100% for those longer distances will require sizable solar systems.
If you already have solar and are in the market for a compatible home charging station, then I highly recommend the WallBox Pulsar Plus.
- Connect to WiFi and Bluetooth
- Charge multiple EVs simultaneously
- Level 2 charges 7 times faster than 120v
- Lacks customer support