MPGe is the U.S. EPA efficiency rating for electric cars. It converts the electricity an EV uses into a petrol-style miles-per-gallon figure, so you can compare efficiency in the way you already understand from mpg. The EPA counts one gallon of petrol as equal to 33.7 kWh of electricity, so a higher MPGe means the car travels further on the same amount of energy.
Key Takeaways
- MPGe converts an EV’s electricity use into a petrol-style figure: 33.7 kWh counts as one gallon.
- Higher MPGe is better; lower kWh per 100 miles is better. They are the same fact read two ways.
- Compare ratings within a size class, and check the figure for the exact version you are buying.
- A more efficient car costs less per mile and needs less charging time at home.
How the Number Is Worked Out
The EPA tests the car and measures how much electricity it takes from the wall to drive a set distance, then converts that electricity into a gallon equivalent using the fixed 33.7 kWh figure. The window sticker shows a combined MPGe plus separate city and highway ratings, because efficiency changes with speed and driving pattern — and it also shows consumption the direct way, as kWh per 100 miles. FuelEconomy.gov lists the ratings for every model on sale.
What MPGe Means in Money
Because the conversion is fixed, you can turn any MPGe figure back into energy and cost. The examples below use the U.S. average residential electricity price of 18.31 cents per kWh (EIA). They are worked examples with rounded figures, not promises — your tariff and your car will differ.
| Rating (example) | Electricity per 100 miles | Energy cost per 100 miles at home |
|---|---|---|
| 90 MPGe | About 37 kWh | About $6.85 |
| 110 MPGe | About 31 kWh | About $5.60 |
| 130 MPGe | About 26 kWh | About $4.74 |
The pattern is simple: the more efficient car needs less electricity for the same trip, so it costs less to run and spends less time charging. For the wider comparison with petrol, see our article on whether charging an electric car is cheaper than gas.
MPGe Runs the Opposite Way to Consumption
MPGe and kWh per 100 miles describe the same thing from opposite directions. With MPGe, higher is better. With consumption, lower is better. Shoppers trip over this more than any other part of the sticker. If you prefer the direct measure, our guide to how many kWh it takes to charge an EV works through the consumption side — battery sizes, charging losses and what a full charge actually uses.
How to Use MPGe When You Compare Cars
- Compare like with like. A large SUV will post a lower MPGe than a small hatchback, just as it would a lower mpg. Efficiency only ranks fairly inside a size class.
- Check the exact version. Ratings change between versions of the same model — motor count and wheel size both move the figure — so read the sticker for the version you are actually buying.
- Remember what it does not measure. MPGe rates the car, not your tariff or your climate. Cold weather, high speeds and a full load all push real consumption above the label figure.
- Use it to size your charging. A more efficient car adds the same miles from fewer kWh, so it needs shorter or less frequent sessions at home.
An Efficient Car Asks Less of Your Charger
Whatever the rating, home charging covers the miles while you sleep. The U.S. DOT puts Level 2 charging at 7 to 19 kW, adding about 10 to 20 miles of range per hour. A portable unit such as the EV-ACS3210T 32A NACS portable charger (about 7.7 kW, NEMA 14-50P, IP66) suits most homes, while the EV-ACT5006T 48A Level 2 wall charger (hard-wired or NEMA 14-50P, 25 ft cable) refills a larger battery faster. How the levels divide the work is set out in our comparison of Level 1, Level 2 and DC fast charging.
Frequently Asked Questions
Is MPGe the same as mpg?
It is the same style of comparison, not the same fuel. Mpg measures petrol burned; MPGe measures electricity used, converted at 33.7 kWh to the gallon. A car rated at 110 MPGe uses the energy equivalent of one gallon to travel 110 miles.
Do plug-in hybrids have an MPGe rating?
Yes. A plug-in hybrid carries two ratings: MPGe for its electric driving and a conventional mpg figure for running on petrol. Both appear on the window sticker, because the car uses energy both ways.
Why is my real efficiency worse than the label?
The rating comes from a standard test cycle. Highway speeds, cold weather, heating and air conditioning, heavy loads and brisk acceleration all use more energy in real driving — the same reasons a petrol car misses its official mpg.
Related Reading
- How Many kWh Does It Take to Charge an EV?
- Is Charging an Electric Car Cheaper Than Gas?
- Does Level 1 Charging Use More Electricity Than Level 2?
- Level 1 vs Level 2 vs DC Fast Charging: A Practical Comparison
