This is fun to see; fuels and engine talk. Right up my alley from my BP Oil days when fuel specification was my job [along with market strategy].
<this is one reason for the interest in 'fuel cells' - possible to get about 85-90 % of the energy content of fuel as electricty. That's 3 to 3.5 times an IC engine.>
Don't forget the energy efficiency has to be measured from the beginning. Meaning the original source of the energy, be it photovoltaic cells, or production wells, or planting the agrifuel crop needs to be considered and all costs and energy losses added on.
The capital cost matters. An efficient fuel cell is not much use if it costs $200,000 due to platinum prices or something.
The electricity has to be converted to wheel rotation where the rubber meets the road and that process loses some energy too.
As you said, the high compression ratio for diesel engines improves energy efficiency. Same for petrol engines [gasoline in American].
As you also said, engines haven't improved much in the basic designs since early in the 20th century. It fascinated me how much Mr Ricardo and others had done by 1920 or thereabouts. In the late 1980s, BP used Ricardo as consultants and Ricardo did research on engines. It was very much into tweaking by then.
But there were still good gains being made in control technology such as engine management systems, individual cylinder knock control and other electronic trickery. Stopping the engine helps efficiency. Regenerative braking adds surprisingly little, but is cool to do. I doubt that it's economic at present, but people like it, like recycling rubbish which should just be chucked on a heap.
When vehicles are designed with motors on each wheel, making regenerative braking really easy and improving braking control, then regenerative braking would be worthwhile.
I like the idea of a vehicle with 5 moving parts = the vehicle itself in relation to the road and each wheel rotating and turning. Okay, there would need to be an air-conditioner too and that would have moving parts and radio knobs would rotate.
Maybe there would be a joystick too, to control the vehicle, but I expect the idea of having humans control a vehicle moving at 200 kph in close proximity to other vehicles being similarly controlled by something like a monkey will seem insane. Vehicles will be electronically controlled, travelling very fast and very close together. Human reaction times are something like half a second [if they are paying attention] whereas electronic/photonic reaction times are microsecond times.
With gpsOne and other position location systems, vehicles would know where they are within centimetres.
Mqurice |
