FIRSTLY, the maths, which are simple but vital when considering whether a plug-in hybrid is the right choice for you.

For starters, the Range Rover Sport PHEV 400e commands a £5,000 premium on the price for a conventionally fuelled version.

Next comes the amount of miles you might travel regularly, because the Sport PHEV will carry you for 31 miles using electric power only. In other words, if that is the limit of your motoring, you will never need to visit a fuel station again.

The conclusion is that if you are driving at least half your mileage in electric mode, then this car will make sense. And if you add to the figures the lack of a congestion charge and company tax benefits that come with a CO2 emissions figure of 64g/km it will become even more attractive to some drivers.

The PHEV combines the redoubtable 300hp four-cylinder Land Rover Ingenium petrol engine with a 85kw electric motor and 13kw lithium-ion battery to produce a total output of 404hp from the permanent four-wheel system.

That’s a serious amount of power in anyone’s book, and enables this strapping but indeed sporty beast to shift from 0 to 62mph in 6.3 seconds and climb to a top speed of 137mph.

On the downside, the storage area for the battery under the boot floor causes a slight lip in the usually flat Range Rover Sport luggage area and that battery has ousted the spare wheel, although you can opt for a bagged spare wheel. That does, of necessity, mean a compromise on space, however.

On the road, the PHEV delivers what Range Rover describes as “the best of both worlds” in that it uses electrical energy reserves to provide the power and capability required by the driver.

You get the same luxurious interior, of course, and the unrivalled off-road ability, and the technology on offer at your fingertips is a big bonus. There are two touchscreens, which enable functions normally housed together on a single screen to be accessed without, for example, having to choose satellite navigation over media information.

On longer journeys, drivers can use a save function to deploy the EV-only range for a specific part of their journey, for instance when entering a congested area.

The EV mode is manually selected using a button on the console and gives the PHEV a top speed of 85mph.

Charging the PHEV is a straightforward affair. There’s a charging point behind a panel on the grille to which the charging cable is attached. Three types of cable are available, with the home charging lead – which connects to domestic power supplies – coming as standard.

For faster recharging, a multi-function cable for use at higher power charging locations and suitably equipped homes ia available, and this can reduce the charge time to as little as two-and-three-quarter hours. Similar performance is available with the public charging cable, which is compatible with service stations and the like.

Charging status can be monitored via two illuminated strips that sit either side of the charging socket behind the grille. You can even monitor the charge status through an app that will also warn of any charging error or if the cable has been removed forcibly.

At first it seems a little odd to hear the faint whine coming from under the bonnet rather than the tell-tale noise of a diesel or petrol engine, but there can be no doubt that this is the path that in part all manufacturers will be heading down sooner or later.

The Range Rover Sport PHEV does it with aplomb and with an underlying capability to thrill to thrill and amaze, depending on whether you are off-road or need to get somewhere in a hurry.

AT A GLANCE

Rane Rover Sport PHEV

Price: £73,800

Engine: Four-cylinder 2.0-litre Ingenium petrol engine combined with electric motor to produce 404hp

Transmission: Automatic eight-speed

Performance: 0 to 62mph in 6.3 seconds; top speed 137mph

Economy: 100.9mpg combined

CO2 emissions: 64g/km

RATINGS

Performance: *****

Economy: ****

Ride/Handling: *****

Space/Practicality: ****

Equipment: *****

Security/Safety: *****

Value For Money: ****

OVERALL: ****