Tech in a Flash: Extended-Range Electric Vehicles (EREV)

You’ve probably already spotted the acronym EREV in your automotive reading, including on our sites. The letters stand for “Extended-Range Electric Vehicle.” And no, it isn’t just another way of saying plug-in hybrid. In fact, it’s a distinct approach. Let’s look at it together.

• The gas engine never turns the wheels: it only works as a generator.

• The battery is bigger than in a plug-in hybrid, which boosts electric range.

• Total combined range, electric and gas, can top 1,000 kilometres.

A common mix-up

The confusion is understandable. On paper, both technologies let you drive in electric mode most of the time, with a gas engine taking over for longer trips.

What’s different is the mechanics behind it, more specifically the relationship between the gas engine and the electric motors.

A gas engine with no ties to the wheels

In a typical plug-in hybrid, the gas engine can drive the wheels directly at any time. It works alongside the electric motor or motors, depending on driving conditions and the model’s setup (two- or all-wheel drive).

In an EREV, the combustion engine has no connection to the wheels. Its only job is to spin a generator that recharges the battery. Propulsion, meanwhile, stays 100% electric no matter how far you drive.

That’s why the name puts electric vehicle first, not hybrid.

Rethinking range

Beyond the different setup, the real change is the range.

Since the gas engine has just one job, generating electricity, engineers can fit a much bigger battery than in a traditional plug-in hybrid, because the gas engine itself can be much smaller. That often translates into noticeably more all-electric freedom, typically between 150 and 250 kilometres, before the generator even kicks in.

And when combined with gas, total range can climb past 800, even 1,000 kilometres.

And since the gas engine’s whole purpose is to recharge the battery, you can rack up electric kilometres over long distances, meaning more of the trip happens in electric mode even on very long journeys.

The Chevrolet Volt: forgotten pioneer

If the concept sounds new, it isn’t. The Chevrolet Volt, launched in 2010, pioneered this approach in North America. Its Voltec architecture relied primarily on electric propulsion, with the gas engine acting as a range extender. Unlike today’s EREVs, though, the Volt could also send a portion of the combustion engine’s power directly to the wheels under certain conditions, particularly at higher speeds.

The big comeback

The technology is indeed making a strong return. Ram still plans to launch its 1500 REV, an extended-range electric pickup promising about 240 kilometres in pure electric mode and close to 1,100 kilometres total thanks to a V6 engine acting as a generator.

Scout Motors, the brand revived under Volkswagen’s wing, is also betting on this approach for its upcoming Terra and Traveler models. Jeep is preparing an EREV version of its Grand Wagoneer. And Hyundai, along with its Genesis division, has confirmed its own extended-range models are coming by 2027.

Why now

Anyone who’s owned a Chevrolet Volt will tell you an EREV offers the best of both worlds: the quiet ride and instant torque of an electric vehicle every day, without the range anxiety on a long trip.

Much like a plug-in hybrid, but with the added benefit of greater electric range.

For big vehicles, like full-size pickups and SUVs that have room for a large battery, the formula clearly has a future.

Whether it’s the one that ultimately wins out remains to be seen.