Mygreenwheels

Any boy racers out there should be asking this question. Why are major manufacturers not putting more emphasis on in-wheel electric drive systems?

So often EVs are dismissed by drivers as glorified golf carts, but if you look at the performance claims of the electric cars that have in-wheel motors, they promise a satisfyingly white-knuckled experience for the most ardent petrolhead. Take the ZAP-X that I wrote about last week - its in-hub electric motors deliver 644 horsepower in all wheel drive mode and a top speed of 155mph.

Then there's the PML Mini QED that was show-cased last summer. With four 160 horsepower electric motors it can reach 150mph and does 0-60 in 4.5 seconds. I'm not remotely technical, but even I can see that there's something going on here.

And it gets even better. Apart from performance, there are many more advantages to having your motors tucked away inside the wheels.

For a start, in-wheel technology is adaptable to other vehicle chassis, so there's no need to design from scratch and you can benefit from all the work that's gone into low cost component sourcing for a production vehicle.

These motors also save masses of space and weight and use energy more efficiently by allowing for a four wheel drive system without need of transmission, driveshafts, differential gears or other complex mechanical components. The resulting extra space facilitates the storage of batteries, giving the option of allowing for extra modules to be fitted to improve power and range - or just making more space for passengers and their clobber. There's loads more, so if you want the full science bit, here it is. Dazzling stuff.

The reason that PML originally chose the MINI to demonstrate their technology was because of its broad appeal and iconic styling. It's also heavy for its size and doesn't offer much space to integrate the component set required for a top performance electric car, so they took the view that if they could successfully convert this vehicle, anything else should be a dawdle by comparison.

Starting with a standard BMW Mini One, PML discarded the engine, the disc brakes, the wheels, and the gearbox. These components were replaced by four electric wheels, a lithium polymer battery, a large ultra capacitor, a very small ICE with generator (so small it almost fits alongside the spare wheel), an energy management system and a 'sexy' in-car display module. It's worth having a look at the specification just to begin to understand what fabulous technology has gone into this car.

PML proudly claims on its website that "(This) is truly an outstanding example of British innovation at its best!" I'm totally with them on that one and I'm just wondering what it takes for them to be discovered by more EV manufacturers. And just imagine what they could do for multi-wheeled truck and bus manufacturers. 

The whole auto world seems to be battery-obsessed at the moment, but I'm starting to think that in-wheel motor technology is much more of a silver bullet when it comes to creating an electric car that ordinary drivers will actually desire.