The U.S. Energy Department on Tuesday launched an online tool to promote electric vehicles by comparing the costs of fueling an EV vs. driving on gasoline.
How much does it cost to commute to work or drive across town? The price of gasoline is posted at every corner gas station, but what about the cost of driving on electricity?
How much does it cost to commute to work or drive across town? The price of gasoline is posted at every corner gas station, but what about the cost of driving on electricity?
The U.S.. Department of Energy’s eGallon provides a quick and simple answer to this question and allows electric vehicle (EV) drivers to see how much they can save on fuel by using electricity instead of gasoline.
The price of an eGallon tells consumers how much it costs to drive an EV the same distance you could go on a gallon of unleaded gasoline in a similar car. It’s that simple. We take the average distance that a gasoline-powered vehicle can drive on a gallon of gas (28.2 miles for comparable 2012 model year cars), and then calculate how much it would cost to drive the average EV that same distance. Because electricity prices are a little different state to state, our eGallon tool shows how much an eGallon costs in your state, and compares it to the cost of gasoline.
As you can see, on average, fueling your car with gasoline costs roughly 3 times more than fueling with electricity.
If you chart the price of gasoline and the eGallon price over time, you’ll notice something else. Gasoline prices often spike up and down erratically because they’re linked to international oil markets. Events half a world away can drive up the price we pay at the pump. High prices and uncertainty are a heavy burden for American consumers. On the other hand, the cost of electricity is regional and much more stable, so you generally don’t have to worry about the wild gyrations seen in gas prices.
The eGallon price arms consumers with a little bit more information to compare the costs of driving an electric car to the cost of gasoline, but it doesn’t measure some of the other benefits of driving on electricity. There are significant environmental benefits -- particularly as the share of electricity that comes from clean and renewable energy increases -- as well as benefits for America’s energy security. Instead of spending $1 billion a day on foreign oil, with electric vehicles and other technologies we can power our cars, homes and businesses with American energy.
As electric vehicle technology continues to improve and the cost of the vehicles continues to fall, more and more Americans are making the switch to electric. If you’re curious about how much you could save, be sure to check out energy.gov/eGallon for the latest eGallon price in your state.
For most drivers, a trip to the fuel pump is an easy reminder of the day-to-day cost of gasoline or diesel. But for electric vehicle (EV) drivers, who typically charge their car at home, there isn’t a similar measurement to determine the cost of driving on electricity. To help both current and potential EV drivers better understand the cost of driving an EV, the Energy Department created the eGallon.
What is the eGallon?
The eGallon represents the cost of fueling a vehicle with electricity compared to a similar vehicle that runs on gasoline. For example, if gasoline costs $3.60 a gallon in your state and the eGallon price for your state is $1.20, that means that for $1.20 worth of electricity you can drive the same distance as you would for $3.60 worth of gasoline.
How is eGallon calculated?
To determine the eGallon price for each state, the Department of Energy calculates how much electricity the most popular electric vehicles would require to travel the same distance as similar models of gasoline-fueled vehicles would travel on a gallon of gasoline. That amount of electricity is then multiplied by the average cost of electricity for the state. This gives consumers a clear comparison of the cost of driving on electricity vs. a similar sized car that uses gasoline.
For more on how eGallon is calculated, download the eGallon methodology.
Why do gasoline prices swing so wildly? Does the same thing happen with eGallon prices?
Gasoline prices are tied to the global oil market, which is driven by international events that are difficult to predict, control or prepare for. Unrest in an oil producing country on the other side of the world can drive up the price of gasoline in your neighborhood, seemingly overnight.
In contrast, the price of electricity is determined by local markets or state utility commissions. This means that electricity prices tend to be very stable over time -- creating a lot less uncertainty about fuel costs for an electric vehicle. The chart below shows how the prices of gasoline (the green line) and electricity (the blue line) have fluctuated over the past 10 years.
Why does the price of an eGallon vary by state?
Just like the price of gasoline, the average electricity price is different for each state. Electricity is generally produced close to its customer base, and different regions have different regulations and resources (e.g. coal, natural gas, wind, etc.) that affect the cost of electricity production. Traditionally, the cheapest way to produce electricity is through “mass production” -- at a large scale. So each region may have only one electricity company. Local governments work with this company to set a price for electricity that is reasonable for consumers. In many places across the U.S., electricity prices are set by regulators, not the market.
How does “off-peak” charging affect the eGallon price?
In some places consumers are charged “off-peak” rates for fueling their electric vehicles at night when electricity demand is low. This “off-peak” electricity rate leads to even bigger cost savings for driving on electricity. The eGallon is based on the average cost of electricity for residential consumers.
Why do we need eGallon?
The cost of driving an EV depends on the cost of electricity, which is measured in kilowatt hours. Yet, when consumers think of the cost of driving, it is usually determined by the price of a gallon of fuel. The eGallon provides a metric that is easily comparable to the traditional gallon of unleaded fuel -- the dominant fuel choice for vehicles in the U.S.
How is eGallon related to the EPA’s MPGe rating?
eGallon and MPGe are not related. eGallon is a measurement of the cost to drive a comparable vehicle the same distance you could go on a gallon of gasoline. MPGe is a measurement of how efficiently a vehicle uses energy based on the number of British Thermal Units (BTUs) in the fuel.
How often is the eGallon price updated? What about the gasoline prices listed with eGallon?
Energy.gov will release the state and national averages for eGallon in coordination with the Energy Information Administration’s (EIA) monthly reports on electricity prices. The eGallon price is calculated using the most recently available state-by-state residential electricity prices. The state gasoline price above is either the statewide average retail price or a multi-state regional average price reported by EIA. The latest gasoline pricing data is available on EIA’s webpage.