MHEV (mild hybrid electric vehicle)

A mild hybrid (MHEV) is a gasoline or diesel combustion-engine car with a small electric assist: a battery and electric motor that help power the vehicle and can let the engine shut off when it stops. The U.S. Department of Energy states that mild hybrid systems cannot power the vehicle using electricity alone. Fueleconomy.gov adds that they use stop-start technology and regenerative braking.

That is why CarPairly classifies mild hybrids by their engine rather than as a separate hybrid powertrain: a gasoline mild hybrid is listed as ICE, and a diesel mild hybrid as Diesel. Unlike a full hybrid (HEV), an MHEV has no electric-only driving mode, so from a shopper's point of view it is compared like a conventional combustion-engine car: same fueling, same units, same comparisons. You will therefore find mild-hybrid models in our Gas branch under the ICE or Diesel powertrain, with the mild-hybrid hardware treated as an engine feature rather than a different category of car.