Battery electric vehicles (BEVs) run off one power source only - the electric battery. There is no combustion engine present which means they are the cleanest option and never produce tailpipe emissions and hence the most sustainable.

They do however have range anxiety, if you run out of electricity that’s it, just like if you ran out of petrol or diesel; hence there are some additional things you need to consider before purchasing a pure electric vehicle.

Range-extended electric vehicles (E-REVs) essentially bridge the gap between plug-in hybrids and pure electric cars. The vehicles run on electricity only, but unlike pure electric vehicles they also have a generator on board to recharge the battery when it is depleted. This eliminates range anxiety as the vehicle will run as long as it is refuelled with petrol. The vehicle is never directly powered by the petrol engine like other hybrids and is always driven by the electric motor. This provides fuel consumption and emission benefits over a plug-in hybrid electric vehicle (PHEV).

Plug-in hybrid electric vehicles (PHEVs) use the same technology as a full hybrid, but they have a larger battery capacity and can therefore travel for extended distances in pure electric mode - typically between 10 and 30 miles. Unlike conventional hybrids, plug-in hybrids can be recharged, and if used for short, frequent journeys will achieve the same zero emissions as a pure electric vehicle.

Only once the battery is depleted will the combustion engine kick in and power the car like a conventional petrol/diesel vehicle. Plug-in Hybrids are most efficient when regularly charged and cover a high percentage of driving in electric only mode.

A hybrid vehicle makes use of both a conventional combustion engine and an electric motor, either working independently or in conjunction with one another. It uses an electric motor to assist in providing more power to the vehicle when needed, and can also run on pure electric alone for a mile or so when driving at very low speeds. The full hybrid system works at its best when the vehicle is regularly accelerating and braking, as regenerative braking is used to recharge the battery.