Compare efficiency, then calculate your own energy costs

Shopping for a used Tesla or comparing an electric vehicle with a gasoline car? MPG and MPGe answer an efficiency question—not how much your Southern California commute will cost. Use the rating for the exact model year and configuration, then add your own mileage and energy prices.

What MPG and MPGe mean

MPG means miles per gallon. MPGe means miles per gallon of gasoline-equivalent: it compares distance traveled using an equivalent amount of energy. EPA uses 33.7 kilowatt-hours of electricity as the energy equivalent of one gallon of gasoline.

MPGe is not a dollar conversion. A car rated at 100 MPGe does not necessarily cost one quarter as much to fuel as a 25-MPG car. Electricity and gasoline have different prices.

EPA MPGe values include charging losses under its Level 2 AC charging assumptions. They are not simply the energy shown leaving a battery. See EPA’s explanation of fuel economy and EV testing.

A simple comparison worksheet

For a gasoline car, divide the miles you plan to drive by MPG, then multiply by the price per gallon. For an EV, multiply miles divided by 100 by the label’s kWh per 100 miles and your electricity price per kWh. These are planning estimates, not a quote or a promise of savings.

Gas example: 1,000 miles ÷ 30 MPG × $4 per gallon = about $133 in fuel.
EV example: 1,000 miles ÷ 100 × 30 kWh per 100 miles × $0.30 per kWh = $90 in electricity.
Different charging price: At an illustrative $0.50 per kWh, the same EV calculation becomes $150.

All prices and efficiency values above are hypothetical. They are not current California rates or ratings for a particular vehicle. Replace them with your own figures. Add applicable session, parking, idle or other charging fees separately, and do not treat energy cost alone as total ownership cost.

Read the label without confusing efficiency and range

Higher MPGe indicates greater energy efficiency; lower kWh per 100 miles means lower electricity consumption over the same distance. Range is a separate estimate. The label’s annual-cost figure also uses assumptions that may not match your driving or electricity price. See the official electric-vehicle label guide.

A used vehicle’s original label is a comparison starting point, not a measurement of its present battery condition. Ask about the exact car’s condition and available records. Do not use a high MPGe rating as proof of battery health.

Make the comparison fit your Southern California routine

Write down your usual weekly mileage, including errands rather than only the commute.
If charging at home, use the applicable price and time period from your own electricity plan—not a statewide average.
If relying on public charging, check the stations you actually expect to use and their current pricing and access terms.
Keep charging convenience separate from cost. A cheaper session is not automatically practical if it adds a long detour.
Compare insurance, purchase price and other ownership expenses separately before choosing a vehicle.

Questions to bring when comparing used cars

Record the model year, trim and configuration for each candidate. Ask which efficiency rating applies to that car and whether its equipment has changed. For a plug-in hybrid, compare both its electric-use information and gasoline MPG rather than treating one MPGe figure as the whole story.

Browse used Tesla inventory or all used vehicles at Premium Autos. Confirm availability and whether the specific vehicle is at Norco or South El Monte before traveling.