The rise of electric vehicles (EVs) has led to increased demand for reliable charging solutions. While home and public charging stations are the most common methods, some situations call for alternative power sources. One question that often arises is whether a diesel generator can charge an electric car. The answer isn’t a simple yes or no—it depends on several factors, including the type of generator, the car’s charging requirements, and efficiency considerations.
Can I Charge an Electric Vehicle with a Generator?
Yes, you can use a generator to charge an electric car, but there are some important things to consider:
- Generator Type – Not all generators are suitable for EV charging. You need one with a stable output to avoid voltage fluctuations that could damage the vehicle’s charging system.
- Power Output – The generator must provide enough power for the EV charger. Most Level 1 chargers (standard 3-pin plug) require a generator output of at least 2.5kVA-4kVA, while Level 2 chargers need significantly more—often 9kVA or higher.
- Fuel Efficiency and Cost – Running a diesel or petrol generator over long periods can be costly and inefficient compared to grid charging.
- Emissions and Regulations – Generators produce emissions, which may contradict the environmental benefits of driving an electric vehicle.
- Safety Considerations – Charging with a generator should always be done in a well-ventilated area, away from enclosed spaces to prevent carbon monoxide build-up.
What Size Generator Do You Need?
The size of the generator depends on the EV model and charging speed required:
- For Level 1 Charging (120V, ~1.5kW-3kW) – A 4-6kVA generator should be sufficient.
- For Level 2 Charging (240V, ~7kW-22kW) – A much larger generator, typically 12-30kVA, is needed.
- Fast Charging (DC Rapid Charging) – Most portable generators are not powerful enough to support rapid charging stations.
- Standby/Backup Generators – Larger standby diesel generators located at home or work can provide reliable power for EV charging during grid outages.
Pros and Cons of Charging an EV with a Generator
Pros:
One of the biggest advantages of using a generator to charge an electric vehicle is its ability to provide off-grid charging. This is particularly useful for those traveling in remote areas where traditional charging infrastructure is unavailable. Having a generator ensures that your EV remains powered, even in locations without a charging station nearby.
Another key benefit is backup power. During power outages, a generator can keep your EV running, making it a useful emergency solution. Whether due to extreme weather or grid failures, having a generator can prevent your vehicle from being left without charge when you need it most.
Flexibility is another major advantage. A generator is not limited to charging an EV—it can be used to power various other electrical devices and appliances. This makes it a versatile solution, particularly for those who rely on portable power sources for work, travel, or outdoor activities.
Cons:
Despite the benefits, there are also notable downsides to using a generator for EV charging. One of the biggest drawbacks is inefficiency. Generators consume fuel to generate electricity, and energy is lost during the conversion process. This makes them far less efficient compared to grid-based charging options.
Another significant concern is the environmental impact. Running a diesel generator produces emissions, which can offset the eco-friendly benefits of driving an electric vehicle. Those looking to minimise their carbon footprint may find that generator-based charging contradicts their sustainability goals.
Additionally, generators come with issues related to noise and maintenance. Many diesel generators are loud, which can be disruptive, especially in residential or quiet environments. They also require regular servicing and fuel refills, adding to the overall cost and effort of using one for EV charging.
When Would a Generator Be Useful for EV Charging?
There are specific situations where using a generator makes sense:
- During Emergencies – If power outages occur, a generator can keep your EV running.
- In Remote Locations – Those traveling in areas without EV infrastructure may need a backup charging option.
- For Off-Grid Living – People living off-grid with solar or wind power may use a generator as a secondary source.
- For Event Support – Temporary setups such as festivals or film sets might use generators to charge EVs.
Are There Better Alternatives?
Using a generator is not the most efficient way to charge an EV, but there are alternatives:
- Solar Generators – Some high-capacity solar power stations can charge EVs over time.
- Battery Storage Systems – Large battery banks can store electricity from renewable sources.
- Hybrid Charging Solutions – A mix of renewables and backup generators can be more sustainable.
Is It Worth It?
While it is possible to charge an electric car with a generator, it is not always practical. For occasional or emergency use, a generator can be a useful backup option. However, due to inefficiency, fuel costs, and environmental impact, it is not a long-term charging solution. If you rely on off-grid charging frequently, investing in renewable energy systems or battery storage may be a more sustainable choice.
At Generators For Export, we specialise in high-quality used diesel generators that can serve as reliable backup power sources for a range of applications, including EV charging. If you’re looking for a generator solution tailored to your needs, get in touch today!
Call: +44(0)1386 553344 | Email: sales@gfe.uk.com