If Chevrolet's Volt and Vauxhall's Ampera look very similar, that's because they are. Strip away the badges, grilles and bumpers and you're left with the same underlying vehicle. Indeed, the pair are built by the same workers on the same production line, at General Motors' Detroit-Hamtramck plant in the United States.
But how similar are these two petrol-electric vehicles when it comes to buying and running one? We've done the necessary delving to find out.
Both the Volt and Ampera are classed as plug-in electric vehicles by the government, so they benefit equally from a £5,000 grant towards their basic on-the-road price. After this helpful handout, the Chevy costs from £29,995 and the Vauxhall from £32,250. That's a big £2,255 hike (or about 7.5 per cent extra) for choosing the Ampera over the Volt.
Premium brand kudos is as absent from the Vauxhall griffin as it is from Chevrolet's gold bow tie, so you might expect some obvious improvement in kit to account for the extra cash. And you'd be wrong. There's only one Volt trim level, and it's very closely matched to the Ampera's base Positiv specification when it comes to counting buttons on the dashboard.
Best for price: Volt
We've known that the Volt and Ampera would compete head to head in the UK for some time, and General Motors spokespeople have mumbled vaguely about the Ampera being a more European vehicle customised for local tastes. It's easy to see that the Volt's bright, ;toothy grin has been replaced with an Ampera's streaked mascara, but the nose job is limited to a few cheap plastic parts – even the headlamps are identical.
Vauxhall says its car has a firmer, more sporty suspension setup, although the difference is more of a tweak than a rebuild. The same suspension components are common to both cars.
When it comes to clever gadgets, it's déjà vu all over again. Put the Volt and Ampera spec sheets side by side and you'll receive an object lesson in how to disguise the fact that two cars have all the same stuff. Would you like electronic climate control or automatic air conditioning? Automatic lighting control or dusk-sensing lamps? StabiliTrak or ESP-Plus? Unscramble the code and it's clear both cars have the same premium specification including keyless entry, leather upholstery, a reversing camera, tyre pressure monitor, Bluetooth and a DAB radio.
For Europe, there is a new “Hold” mode that lets the driver start the engine on demand, creating fresh electricity for driving and reserving on-board battery power for later. This is ideal if you know there will be some city driving at the end of a long motorway stint. American-market Volts don't have Hold mode, but the Ampera does. And interestingly the UK spec Volt has Hold mode too. So it's a dead heat here.
Best for spec: Draw
The Volt comes in just one well-equipped trim level, and the significant options list is modestly brief. You can choose nicer paint, shinier wheels, a better navigation and entertainment system, and that's about it. The no-cost paint options are white or black, beyond which a range of pale metallic finishes cost £495, three-layer "premium" paint is £995, polished alloys are £490 and the stereo upgrade is £1,745.
Browse a Vauxhall brochure and you'll stumble across some familiar numbers. There are two Ampera trim editions, Positiv and Electron, at £32,250 and £33,995. The difference is an improved navigation and entertainment system, and the gap in price happens to be exactly £1,745.
Beyond that, the only real Ampera options are metallic paint at £495 or three-coat colours for £995. There's no shiny wheels option, just the standard aero alloys. Oh, and while black paint costs no extra, "Brilliant" white costs £100. That doesn't sound very brilliant to us.
Best for options: Volt
The white-coated boffins who work out insurance groupings must have found some differences in the cost of spare parts, because they've given the two brands different ratings. The Chevrolet goes into group 22E, while the Ampera slots into the slightly lower-risk group 20E in Positiv trim and 21E in Electron trim.
When it comes time to arrange a policy, however, the more expensive list price of the Ampera trades off against its lower grouping. We asked a meerkat to find us fully-comp prices from household-names like Admiral and Aviva, and saw less than 5 per cent difference between the two cars. With both insurers it was the higher-grouped Volt that was marginally cheaper to insure for the same named driver.
Best for insurance: A narrow victory for the Volt
Awkwardly, Vauxhall hasn't yet announced how much its fixed-price servicing plan will cost, whereas Chevrolet offers a three-year fixed-priced option for £349.
Vauxhall does, however, intend to offer a red-carpet collection and delivery service. When Ampera owners book a service, a replacement car will be driven to their door and the Ampera will be whisked away, to be returned later all shiny and clean. Vauxhall says this unusual level of courtesy won't cost extra, and that servicing will cost less than keeping a diesel Insignia fully stamped.
When it comes to finding a garage qualified to fiddle with a petrol-electric powerplant, Ampera drivers will also have it easier. If you live in Wimbledon or Cambridge you're in luck, as that's where the UK's only two Chevy Volt dealers are based. A more healthy 24 outlets scattered across the UK are certified to safely lift the bonnet of an Ampera.
Interestingly, a Vauxhall spokesperson said you can service a Chevrolet at a Vauxhall dealer and vice versa, without voiding the warranty, which is a big plus if you run a Chevy. The Volt driver won't get the white-glove, door-to-door treatment, of course.
Talking of warranty, both brands offer a robust eight-year, 100,000 mile warranty on the entire drivetrain, relieving many worries about off-the-chart repair bills.
The remaining imponderable is how much value the two cars will retain after a few years of running them around. According to motor industry specialist CAP, the Ampera should retain 35 per cent of its list price after three years and 40,000 miles. Unfortunately CAP hasn't yet made up its mind about the Volt, but a figure dramatically adrift from the Vauxhall seems unlikely.
Best for running costs: Ampera
All things considered and confirmed costs totted up, it's hard to see why you'd want to spend a couple of grand extra to have a Vauxhall badge glued to your extended-range electric car. On paper at least, the Volt looks like a much better financial bet.