MY REGENERATION

Current ads on TV by Toyota intimate that if you have one of their hybrids, you don’t need to charge the battery because it will simply charge itself whilst driving. Internal combustion engines are extremely inefficient machines but the conversion of the primary energy source (petrol) to another form (electricity) just adds to that inefficiency. And that is not even considering the losses in the batteries and electric motors.

I can understand how a petrol motor, running at its most efficient revs and delicately charging the battery might overcome those losses, but I can’t see how a primarily petrol car with electric augmentation can be more efficient than a petrol only car if you only rely on the engine to charge the batteries, especially when the car is 100 to 200kg heavier.

Maybe you could dedicate a technical article to explain this conundrum to lay-people like myself?

It’s true, Steve – using the engine to regenerate the battery pack is spectacularly inefficient. Using deceleration or regenerative braking, on the other hand, most certainly isn’t. – Ed