Sector: Luxury Price: £65,550 Fuel: 44.1mpg CO2: 149g/km

Never one to shy away from filling a market niche with a new model, Audi has modified its flagship A8 saloon for the hybrid luxury market.

The result is the A8 Hybrid – a curious car which combines all the luxury and presence of Audi’s biggest car with the supposed economic and ecological benefits of a petrol/electric hybrid drivetrain.

On paper it sounds great – a 2.0-litre TFSI petrol engine and electric motor working in harmony to create a 245bhp business express with moderate fuel economy of 44.1mpg on the combined cycle and CO2 emissions to rival a small family hatchback at 149g/km.

The problem that the Hybrid has is that its diesel-engined stablemates do the same job much better, and for less money.

A 3.0 TDI A8 L in SE specification and with the same front-wheel drive set-up undercuts the Hybrid by nearly £8,000, offers better fuel economy (46.3mpg) and is much better to drive thanks to its lower weight, more accessible power band and better handling.

Drive the Hybrid in isolation and you will struggle to notice that it’s a four-cylinder 2.0-litre engine under the bonnet thanks to the excellent soundproofing job Audi has done. But then you want to build speed quickly and the engine’s whiney note becomes more intrusive in the cabin. In the diesel you build speed effortlessly thanks to the block of torque at the bottom of the rev range; in the Hybrid it’s all a bit of a commotion as the engine and electric motor furiously spin up to compensate for the lack of cubic inches and torque. It’s not really in keeping with the A8’s relaxed gait.

You can, in theory, drive the A8 Hybrid in EV mode, offering about a mile of zero-emission motoring, which may be handy for the odd trip in congested London, but on the freer flowing roads of the rest of the country it’s fairly pointless. It also drains the battery pack very quickly, as the on-board power meter will tell you.

Everything else about the A8 Hybrid is pure class, though. While the exterior styling may be a bit muted for a flagship model, inside it is a beautifully crafted car with bags of luxury, comfort, equipment and space (although the boot loses 175 litres to accommodate the battery pack).

It is also much cheaper than its luxury hybrid rivals, undercutting the BMW ActiveHybrid 7 by around £4,000 and the Lexus LS600h L Premier by a fairly ridiculous £34,000 (yes, £34,000!), but it will be interesting to see how Mercedes-Benz positions itself with the unique diesel-electric hybrid S-Class due for an imminent launch.

Verdict:

The A8 Hybrid makes a strong case for itself on paper as being the best petrol/electric hybrid in the luxury sector; it’s just not the best Audi A8.

Spec:

Segment: Luxury

Type: Petrol-electric hybrid

Price: £65,550

Fuel: 44.1mpg

Electric range: 1.8 miles

CO2 emissions (tailpipe): 149g/km

Charging Port: N/A