The latest data from the Society of Motor Manufacturers and Traders shows that plug-in hybrid registrations were up by 33.5% in July, compared with 17.5% for conventional hybrids, and just 2.4% for pure electric vehicles. 

However, the fleet industry is awash with cautionary tales regarding plug-in hybrids. 

The fact is that many drivers choosing these vehicles because of their cheap benefit-in-kind (BIK) tax implications are neglecting to plug them in on a regular basis and consequently end up accruing huge fuel bills. 

It's easy to see the technology's  attraction, when you consider leviathans like the Audi Q7 and Porsche Cayenne, which are available with plug-in hybrid powertrains, sit in the same tax band as little city cars.  

Not to be outshone, Range Rover has now added plug-in hybrids to its bells-and -whistles line up, including the recently facelifted Sport version tested here. 

Plug-in powerhouse

From a driving perspective, drivers shouldn't worry that opting for the PHEV will leave them down on performance. The powertrain pairs a 2.0-litre, 300hp petrol engine with an 85kW electric motor to produce a total of 404hp and 640Nm of torque. That's enough to accelerate 2.4t of Solihull's finest 0-62mph in 6.7 seconds - faster than any other powertrain in the range, except for the fire-breathing petrol V8s. 

Drive in a more relaxed style and you'll find the hybrid system switching seamlessly between pure electric power - a 31-mile range is claimed on the battery alone - and petrol-assisted running. Adopt a smooth enough accelerator technique and the transitions are so seamless that at one point we found it necessary to open a window just to check that the engine wasn't running. There is quite an increase in noise from the engine if you get more aggressive with your right foot, however, and in those situations the powertrain can feel a little slow to react to throttle inputs. 

The chassis has little trouble handling the power. Inevitably with such a tall car, there is a little body roll, but it's surprisingly well controlled, and there's lots of grip and traction thanks to four-wheel drive and a huge set of tyres. The only downside is weight. The addition of the battery makes the PHEV around 300kg heavier than the non-V8 petrol and diesel models in the range - which goes some way to explaining those high fuel bills - and this impacts on the Sport's agility in corners. Thankfully, things are a lot better back on the straight stuff and, although the ride is a bit jiggly at times, it's never harsh. Larger bumps are dealt with dismissively, while the brakes are impressively capable.