A typical car engine has four cylinders, the graph of torque output verses revolution is virtually a saw-tooth occupying less than half a revolution. This intermittent output means that it cannot run slowly and certainly cannot re-start itself without an electric motor. Why not ditch the poor old petrol or diesel engine and stick with an electric motor in the first place?
An electric motor suitable for powering a car needs to be no bigger than a biscuit tin and has just two bearings. The electronics needed to drive it is the size of a suit case. Just compare that with the poor old combustion engine. The huge block is almost hidden by the rats nest of pipes required to allow it to comply with emissions regulations.
If the combustion engine was invented today, I doubt that any manufacturer would consider developing the poor old thing, such is its complexity.
I was invited to test drive an electric BMW 1 series today at Vines, Guildford. This mule was produced to demonstrate the practicality of electric propulsion. I had to undertake some tight manoeuvres but being a I series owner I felt comfortable behind the wheel – unlike my passenger responsible for this expensive prototype. My first impressions was the smoothness of the transmission. No shunting or gear noise was evident. Progress could not have been smoother in the rush hour traffic. It was a strange but satisfying experience being in a silent car in crawling traffic. The engine braking was a little strange at first and I found myself leaving too much space behind the car in front. Later in the drive I experienced the silent acceleration which certainly matched the 123D version – at the relatively low speeds possible on those roads. It was then that I experienced how effective the regenerative brakes could be. It could not be simpler to drive. Although this was a mule, it was seemed very nice car in its own right. What will go into production is this –
O.K. BMW do not have the reputation of building pretty cars and this is no exception. It is not as ugly as the 1 series but It is bigger. You climb up into it which is a little off putting to me. I do not associate tall cars as proper drivers cars – but that’s just my prejudice. However the cabin is a comfortable place to be and it seems well kitted out. I will speak more of this vehicle when I have had a test drive.