MALLORCA, Spain – If you really want a new car to stand out, make sure to include a pair of butterfly doors. This is exactly what BMW did with the i8 back in 2014 ... but the design team didn't stop there. No, a beautifully crafted body was added to complement those intricate portals, as was a complex plug-in hybrid powertrain comprising a petrol engine, battery pack and electric motor. Now the Munich-based brand has taken the concept a step further by developing an electric soft-top to add to the driving enjoyment: meet the new BMW i8 Roadster.

This, however, was not simply a case of lopping off the roof. No, the conversion was a lot more complex than that, particularly since the entire body is formed from-carbon fibre (which doesn't make the crash-testing, roll-over testing and wind buffeting challenges usually faced by a soft-top any easier to solve). That said, due to the inherent stiffness of the shell, very little strengthening was required and the final weight gain was kept to a minimal 60 kg. The fabric roof section is split into two and stored vertically behind the seats, reducing the amount of space taken up (the claimed luggage capacity for the i8 Roadster is 88 litres, as opposed to the 154 litres of the coupé).

As with the coupé, a 1,5-litre, three-cylinder turbocharged petrol engine is mounted at the rear to work with the 96 kW front-mounted electric motor. An additional 11 kW motor is used as a starter motor and to reduce the effects of turbo-lag.

The i8 Roadster's lithium-ion batteries (along with those of the facelifted coupé) have increased in capacity from 7,1 kWh to 11,6 kWh, while power of the motor is upped by 9 kW to 105 kW (plus 250 N.m of torque). The output of the petrol engine remains at 170 kW. The fuel tank holds just 30 litres, which should give a range of more than 400 km. Sensibly, an optional 42-litre tank can be installed, hiking the theoretical range to 600 km.

The Roadster is nearly as exciting to drive as it looks. You see, although it is styled like a supercar, it is not intended to compete with such machines. Instead, it's supposed to be an ecologically advanced, efficient car for the future that just happens to have a decent turn of speed. And this is where it shines, because it provides an almost perfect blend of power and frugality. We have tested this ourselves with the coupé, achieving an impressive 5,52 L/100 km on our fuel route (the official manufacturer’s figure is 2,10 L/100 km).

On the road, the topless car is huge fun to drive. Due to the less-than-impressive sound generated by just about all turbocharged petrol engines, BMW has cheated a bit by adding a feel-good growl that reaches your ears via the sound system. Faux or not, it works very well. This, of course, is coupled to a whistling sound from the electrical side of the powertrain (it's actually more aurally pleasing than you might expect, and could perhaps be compared with the mechanical sounds of some race cars ... at least, it seemed that way to my mechanically appreciative mind).

The steering isn't quite perfect, but comes close thanks to a quick turn-in combined with a sure-footed feel (the i8 Roadster benefits from model-specific tuning for the springs, damping and dynamic stability control system). The car is quite wide, which posed a serious challenge when the sat-nav instructed me to negotiate some ridiculously narrow, car-lined streets in order to avoid a section of road-works.

On the open road, however, acceleration is impressive and flicking through the six-speed automatic gearbox using the paddle shifters is the way to go. The zero to 100 km/h sprint is dispatched in a claimed 4,4 seconds while the top speed is limited to 250 km/h. One surprising displeasure was that the seats, while looking great, caused some discomfort in the legs after a couple of hours of driving.

The roof can be lowered while you're pottering around in traffic at speeds up to 50 km/h, which would be quite handy if it started to rain or the sunshine was pounding you with too many UV rays. A glass screen at the rear can be adjusted to alter wind flow, but I found no problems with the window up or down. In fact, there was minimal wind buffeting at any speed.

My choice of paintwork for the test drive was the new "E-Copper" metallic hue, with copper and brass being some of my favourites from youth when these metals were used quite extensively for a variety of things. The standard wheel size is 20 inches, and you have a choice of turbine, propeller or rail track designs, all of which sound exotic but are actually quite accurate when you see the shapes.

The i8 Roadster is set to arrive in South Africa in June 2018. Should you be interested? Well, if the i8 coupé tickled your fancy, this new topless version should, too. You see, it offers the same sort of driving experience (and potential frugality) as its hard-top sibling, but with yet more flair and wind-in-your-hair thrills. And, perhaps most importantly, all without any significant compromise over the coupé...