The stars of BMW’s future have finally arrived. These are the first official pictures of the founding members of the eco-friendly ‘i’ sub-brand – the family hatch all-electric i3 and the hybrid supercar i8.
Both models are built using BMW's LifeDrive construction. This essentially splits the car into two separate parts – an aluminium Drive section which houses the battery, suspension, and crash structures and a Life passenger section made from CFRP – a material at least as strong as steel but 50 per cent lighter.
Video: watch our video of the BMW i3 at Frankfurt
By using LifeDrive BMW claims to have cancelled out the weight penalty associated with the heavy battery packs electric cars must carry and the evidence suggests they're right. The i3 is taller and wider than a VW Golf, albeit around 30cm shorter, but it weighs just 1250kgs – that’s around 50kgs less than the lightest Golf.
Video: watch our video of the BMW i8 at Frankfurt
The ‘i’ cars come with a few subtle styling updates to mark them out as eco-specials.
A blue ring now circles the badge, and the kidney grilles now have a matching blue background. BMW’s double circle headlights are replaced by U-shaped LEDs and both models take on a more curvaceous design than the firm's conventionally powered models.
The tall hatchback i3 gets a 168bhp electric motor mounted above the rear axle and delivers power to the rear wheels. Acceleration from 0-62mph takes 7.9 seconds and the i3 is electronically limited to 93mph.
Power is drawn from a lithium-ion battery mounted underneath the floor which is fitted with an integrated liquid cooling system to keep the battery at the optimal temperature. In winter, the battery can also be heated by the same method. A full recharge from a standard socket takes six hours, and a quick charge can fill the battery to 80 per cent in just one hour.
On a full battery the i3 manages a 140-mile range according to the US economy drive-cycle and BMW claims that translates to an everyday range of 80-100 miles. Customers who are looking for more flexibility can specify an optional range-extending engine called REx that will be mounted alongside the electric motor over the rear axle.
Unlike this system – which is only ever used to top up the batteries – the engine in the i8 actually provides drive to the rear wheels directly. In the case of the hybrid supercar it’s a 3-cylinder 1.5-litre turbocharged unit with 217bhp which works in tandem with the same electric motor from the i3 to power the rears – though in this instance it produces just 128bhp for a total of 345bhp.
With both units working together, the i8 can accelerate from 0-62mph in 4.6 seconds and on to an electronically limited top speed of 155mph. Alternatively, the i8 can run on electric power alone for up to 20 miles. Official fuel consumption stands at around 104mpg and CO2 emissions are just 66g/km. BMW admits that an everyday figure of around 50mpg is more likely though.
BMW is still referring to both these cars as concepts but what you see here is essentially what you get when they arrive on the roads in 2013. The i3 will carry a price-tag of around £26,000 after the £5,000 government grant for electric vehicles is applied, while the i8 is likely to cost nearer to £150,000.