How efficient are electric cars? Car News

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In contrast, the electric motor of an EV converts over 90% of the electrical energy it consumes into useful work, so its efficiency is over 90%. Add to that the fact that the electric motor can recover some of the energy it puts into moving the car forward by generating electricity as it slows down, and efficiency improves even further.

The Gasoline Gallon Equivalent (GGE) formula devised by the US National Institute of Standards and Technology in 1994 was designed to compare the energy of gasoline with alternative fuels, and it is a useful way to illustrate the huge efficiency gap between combustion engines and electric drives.

According to GGE, one imperial gallon of gasoline contains the energy equivalent of just over 40 kWh of electricity. This means that a typical average electric vehicle with a 64 kWh battery (usable charge) carries about the same amount of energy as 1.6 gallons of gasoline. A 1.5-liter gas car about the same size as this EV will hopefully manage 55 mpg, so 1.6 gallons of gas will get it 88 miles. At a realistic speed of 3.7 miles/kWh, the 64 kWh electric vehicle will travel almost 235 miles. The 148-mile difference is due to the efficiency of the electric powertrain and the energy recovered through regenerative braking.

Hybrid and plug-in hybrid powertrains improve efficiency in various ways, such as recovering energy through regenerative braking under the right conditions and improving the efficiency of the combustion engine by allowing it to operate in cycles more efficient operation that consumes less fuel. Ultimately, the “main engine” of a hybrid remains a combustion engine, which is still inefficient compared to an electric powertrain.