By combining an internal combustion engine with an electrical motor and battery pack, most hybrids today achieve improvements in fuel efficiency by using the electric motor to supplement engine power.
Some hybrids can also operate exclusively using the electric motor at low speeds. Batteries do not require plugging in and are recharged by harnessing the energy from coasting, braking and from the engine.
Ask your favourite rental agency if they rent hybrids and give one a try. (NC)