VAUXHALL is to market its range-extender electric Ampera via a catchy new classification: EREV.

Extended Range Electric Vehicle, that is. I reckon it’s going to become as common parlance as SUV, MPV and, indeed, EV itself. ‘Eeee-rev’… sounds kinda cool, no?

Question is, what it is. Here, I hope, is a simple crib sheet explaining it.

What is it not?
A Hybrid.

In a Hybrid, like a Toyota Prius, you have an electric motor and a petrol engine. The electric motor drives the wheels, until the batteries run out. Then, the engine drives the wheels, with electric assist.

What is an EREV, then?
In an EREV, you have an electric motor, that drives the wheels. When the batteries run out, the electric motor still drives the wheels. Only this time, a petrol engine starts running, producing electricity to feed the depleted batteries.

Sounds similar… what’s the key difference between Hybrid and EREV?
EREVs are SOLELY driven by an electric motor, fed by batteries. In a Hybrid, wheels are turned by BOTH electric and petrol motor. That’s the key difference.

To explain… there are two modes of powering EREV batteries: by plugging them into the wall, or producing electricity on the go from an onboard generator.

Which, here, just so happens to be that petrol motor. But really, it could be anything. Fuel cell? Hydrogen IC? Nuclear reactor? Anything will do, so long as it can make enough electricity. That’s how immaterial the engine is.

In a Hybrid, when the batteries run down, the engine barges the electric motor out of the way and takes over running the show. It becomes a first-line of drive, rather than the supporting role it plays in an EREV.

This means you can view the Vauxhall Ampera as an EV with a 350-mile range. 40 of those electric miles will come from power fed from a 3-hour recharge, stored onboard in the 16kW battery pack.

310 extra miles will then come from power produced in the generator by combusting the fuel in the tank.

After that? You ‘recharge’ – either by plugging it into the wall… or refilling the fuel tank. Or, both.

A little bit of genius? Lord, yes. It’s brilliant. Until battery capacity really rockets, it makes the EV viable. It’s an absolute masterpiece that will make EVs sell to real buyers.

It’s also a potential goldmine for GM. The most significant leg-up the electric car has yet got? I really do think so…

+ Are you as excited about the EREV concept as I am?
+ What do you see as the downsides?
+ Do you think it is better or worse than a pure EV – and why?