Charging Electric Car With Generator – Is it Possible?

If you own an electric car and find yourself in a situation where you need to charge your vehicle but don’t have access to a charging station, a portable generator can be a useful backup option.

However, it’s important to understand that charging an electric car with a generator is not the most efficient or practical method, and it can have some significant limitations and drawbacks.

People like me who own a couple of EVs including a Tesla face the challenge of charging these cars away from the home because charging stations are not still available in abundance like normal gas stations.

Is Charging an Electric Car With a Generator Possible?

Yes, we can charge our EVs using the generator’s power, but you will need a compatible charging cable and a generator that is properly fueled and in good working order. Keep in mind that charging an electric car with a generator can be time-consuming and may not provide enough power to fully charge the vehicle. Generators are also typically not as powerful as dedicated EV charging stations, and they can be noisy and emit harmful fumes.

In this article, I am going to explain how you can charge your electric vehicle using a generator, level 1, and level 2 charging including a Tesla.

How to Charge an Electric Car with a Generator?

It is possible to charge a Tesla electric vehicle (EV) using a portable generator, but it is not the most efficient or practical method for charging an EV.

Portable generators are typically not powerful enough to charge an EV in a reasonable amount of time which I will cover in my next topic, and they can be noisy and emit harmful fumes.

For this test, I am going to use my HONDA EU7000i at 120V because it is an extremely powerful inverter generator, and small portable generators will struggle to produce more amps.

Level 1 Charging:

It refers to the slowest type of electric vehicle (EV) charging, using a standard 120-volt household outlet. This type of charging is often used as an “overnight” charge, as it can take anywhere from 8 to 24 hours to fully charge an EV, depending on the vehicle’s battery size and the charging rate of the outlet.

Level 1 charging is usually sufficient for most EV owners, as it provides a convenient and easy way to charge their vehicles at home.

Let me tell you how I charge my EV.

• My smart electric car has an 18KWh battery so I use a standard 120V outlet.
• Using Honda EU7000i, it takes around 10 full hours to fully charge the car from zero to 100.
• I connected the charger to the generator and let the generator run on ECO mode for a couple of hours. It lets the power build without fluctuations.
• After a couple of hours, I turn off the ECO mode.

If your generator can produce power at 240V, I would advise using a 240V plug. It will rapidly charge the EV.

Level 2 Charging:

It is a faster type of EV charging that uses a 240-volt outlet, similar to the type used for larger appliances like clothes dryers and ovens.

Level 2 charging stations are more powerful than Level 1 chargers and can provide a full charge to an EV in as little as 4-8 hours, depending on the vehicle and the charging station.

Level 2 charging stations are often found at public charging stations, workplaces, and some homes. They are typically more expensive to install than Level 1 chargers, but they can save time and improve the convenience of charging an EV.

Charging my Tesla at 120V

• Tesla has the option to adjust the amount of power coming into the EV.
• At 120V, my generator was giving it about 127V and 16amps or power.
• The problem with Tesla is that it will take more time to charge at 120V compared to a normal-range EV. Tesla cars are equipped with 100KWh batteries.
• The charging at 120V was around 1.8. Dividing it with 100KWh took about 55.5 hours to fully charge the battery. I obviously didn’t have that much time so tried level 2 (240V) charging.

Level 2 (240V) Charging for Tesla

• Tesla provides its own charger for this kind of charging.
• I was getting around 248V and 20 amps which are about 4960Ws.
• Dividing 4.9KW with the Tesla’s 100KWh battery (100KWh/4.9KW), the car should fully charge in 20.4 hours.

20.4 hours is still too long.  Keep in mind that charging a Tesla with a portable generator can be time-consuming and may not provide enough power to fully charge the vehicle. It is generally more convenient and efficient to use a dedicated EV charging station or an outlet in your home or garage. You can check out our article on “how long does a generator last” if you own a portable generator.

You can also read this article from the Duromax as a reference.

Why Small Portable Generators Are Not Good For Charging Electric Cars?

There are several reasons why small portable generators may not be the best choice for charging electric cars:

Power output: Small portable generators typically have a lower power output than dedicated EV charging stations, which means it will take longer to charge an electric car using a generator.

Time: It can take a long time to charge an electric car using a small portable generator, depending on the size of the car’s battery and the charging rate of the generator.

Noise and emissions: Portable generators can be loud and emit harmful fumes, which can be a nuisance for you and your neighbors.

Cost: Using a small portable generator to charge an electric car can be expensive, as you will need to purchase fuel for the generator and potentially pay for any damages or repairs if the generator malfunctions.

Convenience: Charging an electric car with a small portable generator can be inconvenient, as you will need to set up the generator and ensure it is properly fueled and in good working order before you can start charging the car.

Overall, while it is possible to charge an electric car with a small portable generator, it is generally more convenient and efficient to use a dedicated EV charging station or an outlet in your home or garage.