IT can cost quite a lot of cash to save money, especially when buying a new car is concerned.

Take the latest version of Volvo's well received XC90, a big and very Swedish off-roader which is now available with a double dose of engines.

Yes, two of them. And Volvo is so proud of this double that it puts it in the name.

The first part of the Twin Engine moniker applies to the potent 2.0 turbocharged petrol engine lurking under the big, bold bonnet.

But hidden away between the rear wheels is the surprise, in the shape of an electric motor. And Volvo lets either end do all the work (with a fully charged battery good for up to 27 miles of near silent running) or combines both to provide most un-Volvo like performance, with a top speed of 140mph.

More impressive still is the scant 5.6 seconds it needs to bat the XC90 T8 Twin Engine to 62mph; that's the sort of poke a Porsche would have been proud of a decade ago.

Equally as impressive, except this time it probably won't apply to the way you might use the car, is its claimed fuel consumption.

At better than an extraordinary 134.5mpg Volvo is doing what it has to - abiding by the Euro rules that say how a car's thirst is measured, and cars that have a battery charged from a socket do spectacularly well.

In real life you will not get remotely near that quoted figure, although the smoothness associated with pure electric power ought to be some compensation.

A drive on undemanding Cotswolds' roads showed 36mpg, with 11 miles covered on pure electric via a partly charged battery (needing up to six hours to top up from a domestic socket).

Then there's the price hike required to lever the electric motor and its expensive battery (stashed along the car's centre line, between the front seats so it doesn't rob boot space) that ends up the same figure that might buy you a decent new car all by itself.

On the least expensive of the three grades offered on the XC90, the £57,955 Momentum, it adds a not inconsiderable £11,705 to the bottom line compared to the diesel version.

Yes, the hybrid comes with extra goodies like a powered glass sunroof, four zone climate control, air con for the third row of seats (big enough for a couple of passengers up to 5ft 7ins tall) and, wait for it... a gear-lever knob inset with Swedish crystal glass.

The vanishingly small CO2 tailpipe emissions (49g/km) mean the hybrid petrol/electric XC90 pays no road tax and a business user saves a small fortune in payroll deductions thanks to a BIK rate of five per cent, versus 27 per cent for an equivalent diesel.

Volvo says the XC90 is the safest car it has ever built; among the features are seat belts that tighten if it senses you've run off the road and brakes that apply themselves if you turn in front of an oncoming vehicle at a junction. Truly, the age of the self-driving car grows closer by the month.

Volvo is proud of the way the car connects to the outside world, mostly via a big touchscreen that dominates the centre of the dashboard. You can listen to Internet radio stations, check the weather forecast and open podcasts as you drive along while, optionally, there is Apple CarPlay on tap to stream music from Spotify.

The XC90 with diesel, petrol or hybrid power is a lovely place to spend time, with a beautifully crafted cabin, gorgeous seats and what an urban hipster might call 'a cool Swedish vibe.'

Add £2,150 for the air suspension option and you'll have a car that ride smoothly too - knocking off some of the patter of non-air models.

Volvo hopes to sell several hundred hybrids a year, while the diesel XC90 continues to grab the overwhelming bulk of sales. That's a sensible split in the real world.

Buyers with the sort of limited mileage lifestyle that suits this version are going to be very happy with their purchase. Everyone else will be delighted to go diesel.