Understanding Electric Vehicle Fuel Economy Ratings
New electric vehicles from Honda are state-of-the-art money savers. Benefiting from the latest fuel-efficient vehicles is awesome, but understanding how it all works can be kind of intimidating. Apple Tree Honda is here to help. To understand just how much money they can save you at the pump, you have to understand how to read those complicated stickers from the Environmental Protection Agency (EPA), the US government’s watchdog on vehicle fuel economy ratings.
MPG
For decades, consumers could compare a car’s fuel economy with a single simple metric: Miles per Gallon, or MPG. Simply put, MPG refers to the number of miles a vehicle can travel on a single gallon of regular unleaded gasoline. Of course, the accuracy of this rate can vary depending on the type of driving, whether it’s stop-and-go city driving or high-speed highway driving. Other factors, such as cargo and passenger weight, driving up or down steep hills, and even tire pressure, can affect the accuracy of an MPG estimate, which is why a vehicle’s MPG rating should always be considered just that—an estimate. That’s why they always include the famous fine print at the bottom: “actual mileage may vary.”
MPGe
So, how do you compare an electric vehicle’s Miles per Gallon rating if an electric vehicle uses no gallons at all? The EPA uses a Miles per Gallon equivalent (MPGe) which involves another unit of energy: BTUs (or British thermal units). A single gallon of regular unleaded gasoline, if ignited, creates 115,000 BTUs. Therefore, the EPA determines the amount of electricity that equals 115,000 BTUs and then estimates how many miles an electric vehicle can travel using that same amount of electricity. If a lightweight all-electric vehicle can travel 100 miles using the amount of electricity generated by 115,000 BTUs, then that vehicle can travel 100 MPGe, which is pretty darn impressive compared to most gas-powered vehicles.
kW-hrs per 100 miles
Okay, so what about that other rating? You’ll notice in the EPA “Fuel Economy and Environment” sticker (pictured above) there are a lot more ratings than just MPGe. Another important metric for electric vehicles is kilowatt-hours per 100 miles, which you may see written as “kW-hrs per 100 miles” or “kWh/100m.” This figure is very similar to MPGe, but some consider it to be a more accurate rating. kWh/100m is, put simply, the amount of electricity a specific vehicle uses to travel exactly 100 miles.
This may be a more helpful rating because it uses the actual units of measurement you might see on the monthly bill from your home’s electric power utility company: kilowatt-hours. If you plan to charge your new electric vehicle at home, this rating can also help you understand how much it will increase your monthly electric bill.
Let’s Do the Math
Figuring out your bill is pretty easy to determine; figure out how many miles you typically drive in a single year (US average: 13,476 miles driven per person per month), divide that number by 100, and then multiply that number by the kWh/100m rating for the electric vehicle you are considering (28 in the example above). Then consider the amount your power company charges per kWh (US average: $0.125 per kWh) and how much that might increase your bill.
13,476 miles ÷ 100 = 134.76 x 28 kWh/100m = 3773.28 x $0.125 per kWh = $471.66 per year ($39.31 per month)
In this example, you would spend just under $40 per month more on your electric bill to charge an electric vehicle. Of course, when compared to the amount of money you will not need to spend on gasoline at the pump, that figure probably looks pretty good. Another thing to consider—many communities and employers throughout the US have begun offering free EV charging stations, with each one of them providing you with more opportunities to save with an electric vehicle.
It’s important to remember that every vehicle has a different efficiency rating due to varying sizes and engines, and that these ratings are always estimates dependent on other factors as mentioned above. For a better idea of how going all-electric can help you save money (not to mention save the planet), visit us in person or contact us to see what fuel-efficient new vehicles we have available from the Honda lineup.
Image Credit: EPA