Say ‘horsepower’ and most people will ask ‘how many’. In the case of the Naturmobil the shell shocking answer is 1. That’s right, 1 horsepower. Makes sense given that there is just one horse powering this transparent vehicle. The horse stands on a battery powered treadmill – it recharges from the horse’s movement – which gets the four legged beast galloping which subsequently converts the energy to the vehicle’s wheels. So far they’ve maxed out the Naturmobil to a top speed of 28mph, which is darn impressive given the engine. Some sort of “water jacket” keeps the horse cool, while an extra-large colostomy bag captures its “emissions”. Unfortunately, the driver’s seat and horse sit in the same ‘cab’, and that means anyone driving this beast is gonna be sucking down some serious fumes. The likelihood of the Naturmobil ever hitting production is slim to none, but it sure does make a great ‘green’ example.