How to Charge Your Electric Vehicle Using a Portable Generator

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Can a portable generator really charge an electric vehicle? This seems to be an awkward question.  Happily, the answer is yes! Nevertheless, some cautionary steps are in order. As noted, some might find it ridiculous that anyone can suggest using a portable generator to charge a motor vehicle.

It Works During Emergency

However, why do most people buy electric vehicles? Often, it is because they want to save on using gas. However, life is often not always about what we want. Unexpected situations arise. We use generators to serve as backup power source in case of power outages. These outages can occur and affect you while traveling to a remote area or camping faraway. It can be safe and effective, in such circumstances, to charge your car using a generator if you are knowledgeable about how to do it correctly.

We will now tell you all that you should know about using a portable generator to charge an electric vehicle. The first point to note is that you cannot use any kind of generator and expect to charge your car successfully.

Factors to consider when choosing a Suitable generator for EV charging

The generator you choose must have a clean output of sine wave. For this to happen, you need an inverter generator. Some vehicles like the Tesla can easily tell when the output produced is not pure clean sine wave. In such a situation, it just refuses to charge. This safety mechanism is important because a power surge can be quite damaging to the car. For this reason, such vehicles as the Tesla will only charge when the power is stable.

Remember that, theoretically, all inverter generators offer pure sine wave. The reality, however, is far from that. For instance, some inverters have a sine wave that is modified. It can be a modified square wave or a simple square wave. The Tesla car, that we are using as an example, will automatically consider this sine wave as dirty energy and, therefore, will fail to charge. For this reason, always insist on an inverter with pure sine wave effect. Note also that most relatively cheaper generators usually offer modified sine wave rather than pure sine wave.

How to Charge Your Electric Car with a Portable Generator

You have now determined that you have an inverter generator with stable energy and clean pure sine wave. It is ready. You have checked the grounding and found that it is all right. Now, you need to know exactly how to charge your electric vehicle using the generator.

The first thing you should be aware of is the amount of charge needed. Always start with the lowest possible charge rate. Gradually adjust this to about 28-30amps. This is good because it prevents overloading and protects the motor. Remember to adjust the amperage down before you try plugging in the generator.

General Guidelines on Charging Electric Vehicles Using a Generator

Apart from the Tesla car that has been used as example, some other vehicle models can also be charged using a generator.  These include the Chevy Volt and the Nissan Leaf. Both of these can be charged fast using a gas powered generator. While doing these, use the same caveats regarding appropriate sine wave inverter, proper grounding and the right amperage adjustments.

Extra Notable Factors

You need to know that charging an electric vehicle using a portable generator can be a slow and lengthy affair. Good enough, this kind of activity is not usually an everyday activity. It only applies in emergency times. For this reason, you don’t really need to have the car fully charged.

Using a 4000W generator, it will take you 24 hours to fully charge the vehicle. This can mean using several tanks of gas. It is generally practical to use just about one gas tank to charge the vehicle to reasonable power levels rather than do this for a whole day.

Don’t Charge on the Road

If you use a Generac IQ2000 generator, you should be able to get about 12-18 miles per gallon, measuring gasoline value. Can you, however, use the generator while on the road in order to extend the drive time? This might be enticing. It is, however, not safe.

When driving a vehicle like the Tesla, cited above, this would be a breach of warranty since the manufacturers explicitly warn against charging the car using a generator. Otherwise, you would have to make some huge modifications to the car. Both of these options are neither viable nor advisable.

Remember that every generator needs regular maintenance. Unless you do this, the machine will refuse to start the next time you need to use it. If you purchase a generator simply to charge your car, it is likely to have maintenance issues since emergencies do not occur every day. It can take long before you use the generator. This can lead to possible problems when starting the machine in future.

Generac IQ2000 Generator – A Powerful Beast to Charge Your Car

One of the most highly recommended generators for charging electric cars is the Generac IQ2000 generator. Apart from being one of the quietest in the market, it has   good gas consumption rating and powerful capacity. It has a rating of 3.3 amps at 120 volts. It has a maximum AC output of 2000w starting and a fuel capacity of 1.06 gallon.  It can run for 9 continuous hours on this fuel, carrying a load of 500w. Using it, you are able to power multiple devices beside the exciting ability to successfully charge your electric car when necessary.

Portable Generators with the Right Sine Wave Output

The following generator models are guaranteed to offer a pure sine wave output:

Note that it is important to ground the generator while charging your car or vehicle. In most cases, the generator frame usually provides adequate grounding for the machine. The inbuilt charging system for some cars like the Tesla are capable of sensing that the generator is not properly grounded. Again, in such cases, it simply refuses to charge.

You will find most Honda generators behaving similarly. You can solve such issues by using an adapter plug to bridge the ground and the neutral with resister. For certain generators, you may have to literally ground the generator before commencing the charging. You can easily do this using a metal rod driven into the earth and connected appropriately. Use a generator with fair wattage amount. This means about 1500 watts at the least. Do not use a small generator since it is less powerful and will likely not charge the car successfully.

Final Thoughts

All factors considered, a portable generator can offer a cheap and reliable means of backup power supply during times of need. It can help to power your electric vehicle when necessary. For this reason, it is advisable to carry a generator and a little gas whenever you go out on a road trip or some far away camping expedition.

While at home, keep a generator and some gas handy in preparation for the inevitable power outage at some point or the other. Definitely, if you make sure to use an inverter generator with a pure sine wave and appropriate means of grounding, you will be able to charge your electric vehicle successfully, without hassle.

The most highly recommended generator for this activity is the Generac iQ2000. This is because it offers great pure sine wave, contains a built-in bridge for ground neutralization purposes and is relatively affordable when compared to most of its peers.

Alexey P. , Qualified Electrician and Website Founder

Alexey P. , Qualified Electrician and Website Founder

My name is Alexey P. I was born in Poland but later moved to the USA in 1998. As a well-qualified and fairly experienced electrician, I love working with generators. After my family, the generator could easily be my next love in life! No wonder, I am constantly working with this widely used and very fascinating machine. As a result of my professional training in the field of electrical engineering, I am well versed with the key elements of the trade. I am generally knowledgeable with all inspecting codes and important regulations governing electrical components and repair. I presently live in Monticello, Minnesota, USA. Want to know a little about my life outside work? It is no wonder. If you encounter any challenges with your portable generator while on that camping expedition, you can count on me to help deal with that decisively. I love life. I love people. And yes, I love generators, of course!


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