When you’re shopping around for a new hybrid or electric car, you’ll likely come across the acronym “MPGe”. An abbreviation for “miles per gallon of gasoline-equivalent”, MPGe is an energy efficiency metric introduced in 2010 by the Environmental Protection Agency to compare the amount of energy consumed by vehicles powered by alternative fuel to gas-powered cars.
All vehicles that use nonliquid fuels and get their power from compressed natural gas or electricity, such as hybrid and electric models, are rated in MPGe.
Even though MPGe doesn’t necessarily result in an apples-to-apples comparison between the operating costs of the different types of vehicles, they can give you an idea of the gasoline energy equivalent of hybrid and electric cars.
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How is MPGe calculated?
MPGe is calculated by assessing the amount of heat and power a source can produce. MPGe is expressed in BTUs, with one BTU representing the amount of heat required to raise the temperature of 1 pound of water by 1 degree Fahrenheit.
According to the US Energy Information Administration, one gallon of gasoline is the equivalent of 120,333 BTUs. It takes approximately 33.5 kWh to generate the same amount of heat with electricity.
The MPGe value is essential when it comes to determining the amount of energy the owner of the vehicle will most likely pay to use. However, the number isn’t really helpful when determining how much you will pay for the fuel cost of the vehicle because the energy typically comes from an electric meter. In other words, the actual cost depends on the price of electric power in the places you charge your vehicle.
Examples of MPGe values for popular electric vehicles
If you’re interested in finding out what you can expect from an electric vehicle in terms of MPGe, here are the ratings for some of the most popular electric vehicles on the market:
| Car Model | Efficiency (MPGe) |
| Audi e-tron | 78 MPGe |
| Chevrolet Bolt | 118 MPGe |
| Nissan Leaf | 111 MPGe |
| Porsche Taycan | 79 MPGe |
| Tesla Model 3 | 134 MPGe |
| Tesla Model S | 109 MPGe |
| Tesla Model X | 101 MPGe |
| Tesla Model Y | 121 MPGe |
A high-efficiency rating is equivalent to lower electricity costs per mile. For example, the Tesla Model 3 has the highest efficiency rating of the vehicles included. This means that if you take into account just MPGe, making abstractions of horsepower, range, and other metrics, you will pay less per mile to drive the Model 3 than any of the other cars listed.
Electric vehicles offer significant cost savings over traditional gas-powered cars because it’s cheaper to recharge your car than fill the tank with gas. When shopping for a new car, MPGe is a metric that can provide you with an estimate of the vehicle’s fuel efficiency not just for electric cars but also for hybrids.