MPGe is the abbreviation for Miles Per Gallon of gasoline-equivalent. MPGe measures the fuel efficiency of vehicles that operate on fuels like compressed natural gas and electricity, including hybrids and all-electric cars. Gas-powered vehicles use the term MPG (Miles per gallon).
What is MPGe?
As the world transitions away from gasoline-powered cars towards a world of fuel-efficient and environmentally-friendly electric vehicles, there are some new terms you will hear (if you haven't already).
One of those terms is the abbreviation "MPGe," which stands for "Miles Per Gallon of gasoline-Equivalent."
If your next car is an electric car, then the MPGe is something you need to know and understand to help you decide which vehicle is right for you. Let's explore this innovative rating system in more detail.
Their fuel economy can be calculated by using a simple formula to determine how many miles to the gallon of gas the car can get through city and highway driving. However, the exact figures are not obtainable when a battery from a hybrid, plug-in hybrid (PHEV), or all-electric vehicle only uses electricity as its fuel source instead of liquid fuel, so a miles per gallon equivalent was needed for EVs.
The Environmental Protection Agency (EPA) thus came up with MPGe as a unit of measurement for the electric vehicle's energy consumption, making it comparable with gas-powered cars. However, it is important to note that MPGe doesn't necessarily equate to a solid comparison between the operating costs of gasoline engines and electric motors because a wide variation in costs exists between the two types of vehicles. Therefore, the EPA assumes prices represent the national averages.
Using MPGe Ratings to Buy an EV
Research is a must when you are car shopping, and shoppers who want an energy-efficient vehicle with excellent EPA ratings will pay close attention to the MPG or MPGe ratings seen on the window sticker or online dealership ads. When it comes to hybrid and electric cars, however, is that the right way to determine their overall efficiency and what cost savings you may have?
Let's look at the pros and cons of using MPGe ratings when determining which vehicle is right for you.
On the upside, a car's MPGe rating is an excellent way of comparing its energy consumption to that of a gas-powered vehicle. According to U.S. News, if an EV earns an estimated 136 MPGe compared to a gasoline car's 32 mpg, that is a clear indication that the EV is far more efficient. MPGe ratings are also excellent when comparing similar vehicles against each other, especially if you find yourself torn between rival EV models.
On the downside, the MPGe number isn't completely helpful in determining exactly how much you need to budget for your car's electric rates since that energy will most likely come straight from your home's electric meter. MPGe can be challenging to rely on solely because the cost of electricity varies by location. To help car shoppers estimate the cost, all new electric cars show an estimated annual cost for electricity on the window sticker.
Another problem is the miles per driving range; the MPGe may indicate the vehicle's efficiency for comparison sake, but what about your all-electric driving range and how efficiently an EV turns electricity into the distance.
When comparison shopping for hybrid or electric cars, always consider the MPGe ratings together with the driving range. A more efficient electric vehicle costs less to recharge, but how far will it get you on a full charge?
Fortunately, the EPA answers this question with another metric: the range. The Monroney label also indicates a car's kilowatt-hours-per-100-miles rating. The figure tells you how much energy the vehicle needs to travel 100 miles in kWh. Just remember, the numbers are flipped. Unlike MPGe ratings, where a higher number is better, a lower number of kilowatt-hours is better.
Vehicles with the Best MPGe
With more electric vehicles entering the automotive market, the list below of battery-powered cars with their MPGe ratings will change rapidly over the next few years as electric vehicles increase in popularity, become more energy-efficient, and technology advances.
Here’s a list of the most energy-efficient all-electric vehicles for 2022:
- Tesla Model 3 RWD: Combined efficiency of 132 mpg-e, $500/yr estimated fuel costs
- Lucid Air Grand Touring w/19-inch wheels: Combined efficiency of 131 mpg-e, $500/yr estimated fuel costs
- Tesla Model Y Long Range: Combined efficiency of 129 mpg-e, $500/yr estimated fuel costs
- Chevrolet Bolt EV: Combined efficiency of 120 mpg-e, $550/yr estimated fuel costs
- Hyundai Kona EV: Combined efficiency of 120 mpg-e, $550/yr estimated fuel costs
- Tesla Model S: Combined efficiency of 120 mpg-e, $550/yr estimated fuel costs
- Kia EV6 RWD: Combined efficiency of 117 mpg-e, $550/yr estimated fuel costs
- Chevrolet Bolt EUV: Combined efficiency of 115 mpg-e, $550/yr estimated fuel cost
- Hyundai Ioniq 5 RWD: Combined efficiency of 114 mpg-e, $600/yr estimated fuel costs
- Kia Niro EV: Combined efficiency of 112 mpg-e, $600/yr estimated fuel costs
- Nissan Leaf: Combined efficiency of 111 mpg-e, $600/yr estimated fuel costs
- Mini Cooper SE: Combined efficiency of 110 mpg-e, $600/yr estimated fuel costs
- BMW i4: Combined efficiency of 109 mpg-e, $600/yr estimated fuel costs
- Polestar 2: Combined efficiency of 107 mpg-e, $600/yr estimated fuel costs
- Ford Mustang Mach-E: Combined efficiency of 103 mpg-e, $650/yr estimated fuel costs
- Tesla Model X: Combined efficiency of 102 mpg-e, $650/yr estimated fuel costs
- Volkswagen ID 4: Combined efficiency of 99 mpg-e, $650/yr estimated fuel costs
- Mercedes-Benz EQS: Combined efficiency of 97 mpg-e, $700/yr estimated fuel costs
- Audi Q4 E-Tron: Combined efficiency of 95 mpg-e, $700/yr estimated fuel costs
- Mazda MX-30: Combined efficiency of 92 mpg-e, $700/yr estimated fuel costs
Here’s a list of the most energy efficient plug-in hybrid vehicles for 2022:
- Toyota Prius Prime: 133 mpge; $750/yr
- Hyundai Ioniq Plug-In Hybrid: 119 mpge; $750/yr
- Ford Escape PHEV: 105 mpge; $850/yr
- Kia Niro Plug-In Hybrid: 105 mpge; $850/yr
- Toyota RAV4 Prime: 94 mpge; $900/yr
- Lexus NX 450h Plus: 84 mpge; $1,150/yr
- Chrysler Pacifica Hybrid: 82 mpge; $1,200/yr
- Hyundai Tucson Plug-In Hybrid: 80 mpge; $1,100/yr
- Kia Sorento Plug-In Hybrid: 79 mpge; $1,150/yr
- Lincoln Corsair Grand Touring: 78 mpge; $1,200/yr
- Hyundai Santa Fe Plug-In Hybrid: 76 mpge; $1,200/yr
- BMW 330e: 75 mpge; $1600/yr
- Mitsubishi Outlander PHEV: 74 mpge; $1,450/yr
- Mini Cooper SE Countryman: 73 mpge; $1,750/yr
- Audi A7 e: 70 mpge; $1,500/yr
- Volvo S60 Recharge: 69 mpge; $1,550/yr
- Volvo V60 Recharge: 69 mpge; $1,550/yr
- BMW 530e: 64 mpge; $1,750/yr
- Volvo S90 Recharge: 63 mpge; $1,650/yr
- Volvo XC60 Recharge: 57 mpge; $1,950/yr
If you want to check the energy efficiency and MPGe rating for an EV, visit https://www.fueleconomy.gov.
How is MPGe Determined?
The EPA uses the precise amount of electric energy equivalent to the energy in one gallon of gas to determine MPGe ratings. By determining a vehicle's consumption per given distance, the organization can calculate the EV's MPGe. This can be done using advanced computer modeling or an actual driving cycle to convert native units into a gasoline energy equivalent metric.
The amount of energy an electric car owner will most likely pay to use is measured by considering the liquid fuel's tank-to-wheel and an electric vehicle's well-to-wheel consumption. For a battery-powered vehicle, the distance it travels per measure of energy used to travel that distance determines its MPGe rating.
How is MPGe Calculated?
When the EPA devised MPGe in the early 2000s, the government agency calculated that one gallon of gas is comparable to 33.7 kilowatt-hours of electricity in terms of its energy content. For example, a vehicle that uses 33.7 kWh of electricity to travel a distance of 100 miles has an MPGe rating of 100.
Let's use the Tesla Model 3 as an example of how MPGe is calculated:
According to Tesla, the Model 3 Standard Range Plus RWD has a good efficiency rating of 142 MPG-e combined. This means the Tesla Model 3 SR can go 142 miles with the combined highway (hwy) /city driving using 33.7 kWh of energy.
To figure out mpg-e, you take the miles traveled (output) and then divide it by the energy consumed, as it relates to the energy in a gallon of gas (input).
The equation for that is as follows:
- MPG-e = total miles driven ÷ (total kWh of energy consumed ÷ 33.7 kWh/gasoline gallon)
The above calculation is simple enough for full-electric cars without an internal combustion engine; however, it becomes more involved and tricky for a PHEV, such as a Toyota Prius Prime or Chrysler Pacifica Hybrid. Plug-in hybrid vehicles use an MPGe rating when driven solely on electric power and conventional MPG ratings when the gasoline engine kicks in once the battery pack no longer has electric energy.
MPGe vs MPG
The MPGe ratings for electric cars and MPG ratings for gasoline-powered cars may seem similar, but there is a large difference between these two ratings.
As mentioned earlier, the formula for MPGe is 33.7 kWh of electricity = 1 gallon of gas. Bear in mind that while some cars get 100 MPGe, this figure can actually mislead car buyers if you look at it as how much money you will pay for fuel. The most accurate number and calculation is the vehicle's five-year cost of ownership.
MPG is the gasoline equivalent to electric power and is the metric used for traditional gasoline engine vehicles. MPG ratings are significantly lower than MPGe ratings. For example, a gas-powered car with 35 miles per gallon is an excellent rating, while EVs boast 100 MPGe with ease.
The MPG formula is as follows:
- Miles driven ÷ by gallons used = MPG
The History Behind MPGe Ratings
Before 2007, the efficiency of hybrid and electric cars was determined by how many kilowatt-hours (kWh) were used by the vehicle for every 100 miles driven. However, during this time, the government groups found that many people in focus groups didn't actually understand kWh of electricity as a measurement for electric cars or how the EPA calculated EV energy efficiency. Different measurement of efficiency was needed to make it easier for people to understand how far an electric car could go.
The EPA established MPGe as an energy efficiency metric for hybrid and electric vehicles. The metric better relates the amount of energy expended by alternative fuel vehicles compared to traditional gasoline-powered vehicles. Several focus group studies preferred the miles per gallon equivalent, hence the use of MPGe today.
The Monroney Sticker
The U.S. requires a window sticker or Monroney sticker on all new vehicles. The label must be clearly visible to all car shoppers and affixed to the vehicle's window. The window sticker originally got its name from Oklahoma Senator Almer Monroney and should include a listing of all the car's official information.
According to U.S. mandates, there can be a fine of up to $1,000 per vehicle per offense for selling a new car without a visible Monroney sticker. Illegally altered stickers incur additional legal penalties, including jail time and monetary fines.
Alternative fuel vehicle information, such as MPGe ratings, must be included in the Monroney label (window sticker) of new cars and light-duty trucks sold in the U.S. Information about air pollutants and greenhouse gas emissions that environmentally conscious car buyers want to know should also be included.
The EPA and the National Highway Traffic Safety Administration (NHTSA) administered several studies to develop the best way to redesign the Monroney label while still providing car buyers with easy-to-understand and straightforward comparisons across the automotive industry. With the 2012 model year, the new changes became mandatory.
The following information must legally appear on a Monroney sticker on a new car:
— Manufacturer's Suggested Retail Price (MSRP)
— Make and model of the vehicle, as well as its unique vehicle identification number (VIN). This section should also include the car's model year, trim level, and interior and exterior color.
— Safety ratings and crash test scores: This section provides details about the car's National Highway and Traffic Safety Administration (NHTSA) crash test scores.
— Fuel economy and environmental impact: Also known as the EPA sticker, this section includes the car's results in tests for fuel economy, greenhouse gas emissions, and air pollutants. The EPA numbers indicate the vehicle's estimated city, highway, and combined miles per gallon for gasoline-powered vehicles (MPG rating) and the estimated annual fuel costs, and how that rating compares to other similar vehicles. Hybrids, PHEVs, and electric vehicles will have an MPGe rating as the miles per gallon equivalent.
— Engine and transmission details.
— Standard equipment listing. This section lists all the vehicle's standard mechanical, performance, safety, technology, and interior features.
— Pricing of vehicle options.
— Warranty information.