MPG vs MPGe
MPG measures miles driven per gallon of gasoline. MPGe (miles per gallon equivalent) converts electricity to its energy equivalent in gasoline (33.7 kWh = 1 gallon). A 110 MPGe EV uses roughly one-third the energy of a 36 mpg gas car for the same distance.
EPA city, highway, combined
City is stop-and-go testing; highway is steady cruising; combined weights them 55/45. Hybrids excel in city (regen braking, engine-off at lights). Pure-gas cars usually do best on highway. EVs are the opposite of gas — city is more efficient than highway because of regen.
Why your MPG never matches the sticker
EPA tests use a controlled dyno cycle with mild acceleration. Real-world driving adds AC use, cold weather (10–30% range loss in EVs), wind resistance over 70 mph, hills, and aggressive driving. Most owners see 10–20% below the EPA combined number.
What actually saves fuel
Slowing down (75→65 mph saves ~15% on most cars), proper tire pressure (5 psi low = ~2% worse mpg), removing roof boxes (drag), accelerating gently, and combining trips to keep the engine warm. Driving habits affect economy 20–30% — more than any car-shopping decision.
Premium vs regular fuel
Cars that require premium (Audi, BMW, Porsche, AMG, most turbo engines) will lose power and risk damage on regular. Cars that recommend premium will run on regular with slightly less power and economy — usually a wash on cost. Cars designed for regular gain nothing from premium.