Being a really really old person..I often wonder about what happened to something I actually saw on BBC TV many years ago.
A guy named Ferguson (he owned the Massey Ferguson tractor company) was showing off a car he had invented. The vehicle was powered by oil or similar fluid under pressure in a tank under the hood. Two hoses led to each wheel and the fluid was forced against an enclosed fan on each wheel. Then it was returned to the holding tank..when under braking the fluid reversed the jets and stopped the car.
There was a minimum of oil loss to the tank and it was just topped up every few months.
I was just a slip of a lad at the time..but I can still see the driver aiming for a brick wall and stopping easily.
You might think that this system would have had massive publicity..but I never heard anything else about it after that news flash. I would be interested to know if anyone else has ever heard of this?
What a tremendous thing if it worked!! No more engines or gas to worry about..oil companies going tits up all over the place!!
You can't return the depressurized oil which has been used to drive the wheels to the pressurized tank without some mechanical pumping and therefore an outside energy source. Think of blowing up a balloon and using the pressurized air to do some work. The air you've used can't just return to the inside of the balloon because all of the air inside would push it back out. You could use the energy from braking to pressurize some of the oil and put it back into the tank, but you still have some permanent losses from friction and air resistance.
If you had a destination pressurized resevoir after each or all the wheels, the main resevoir could work until the secondaries reached the same pressure as the primary when you hit an equilibrium with no more power transfer - think of one ballon blowing up a second one while you took some of the energy from the transfer.
That’s called a hydraulic drive system, and yes, for specialized equipment (exotic tractors and such) they do exist today. However, one must have a pump to pump the fluid to the hydraulic motors at the wheels.
The mechanical advantage of hydraulics is that there is very little efficiency loss, between the pump and the hydraulic motors, like there is with a traditional engine. I believe the hydraulic tractors that I’ve seen use a traditional diesel engine to drive the hydraulic pump. Much more of that horsepower will go to the wheels than is normally possible.
I think high speed operations are difficult for hydraulic drive vehicals though, and, they simply aren’t practical for a modern automobile.
Personally, I think the high efficiency diesels coming out of Germany, Sweden and Japan are the way to go. I rented one in Germany in ‘06, and that VW Golf performed as well or better than a gasoline powered version. They don’t stink, soot or accelerate slow like the old diesel cars we all remember from the ‘70s and ‘80s—apparently due primarily to advanced electronic controls.