On 18/10/2012 14:08, Doctor Drivel wrote:
John Rumm wrote:
On 18/10/2012 10:59, Doctor Drivel wrote:

"John Rumm" wrote in message
...

Couple that with a 60% CCGT power statin and you have around 50%
gas-to-wheel which is better than any IC engine will achieve.

Indeed - but given the lack of energy density of the best batteries,
still well short of liquid fuels.

You obviously have not heard of supercapacitors.

You obviously have a short memory. I mentioned that they have even
lower energy densities than batteries.

That can clawback ALL the kinetic braking energy and give it back out in
acceleration.

They will store pretty much all of the electrical charge presented to
them and hand it back later. That does not mean that all the kinetic
energy is actually captured in the first place.

However, its not really relevant to the bigger question of storing that
energy in the first place, for which caps are not well suited since
their capacity is low.

They claw back most of
the kinetic energy and give it off to accelerate.

That they are well suited to. But not the bulk storage of energy in
the first place.

But they improve the efficiency greatly in city driving

Indeed, not disputing it.

which most car drive in.

Some do, don't know about most.

Shanghai is using
them now to run EV buses.

Which is irrelevant unless you want a car than needs a charge every
120 seconds.

It is not irrelevant It shows they work, even enough to propel a bus.

No one is disputing they work, but don't try to fool anyone that they
are a solution to the feeble energy density of batteries.

There is good argument to use them augment the performance of batteries
(especially where you have kinetic recovery), but it does not help
increase their capacity by any meaningful amount.

They can also be used for trains, charge at each station with kinetic
reclaim as well, and save the cost of expensive 3rd rail or overhead
wires. Full electric commuter trains are viable without full line
electrification. Overhead wires are ugly.

Trains are already better suited to electric propulsion anyway. You can
even afford to devote a whole carriage to motors and storage if you like.



--
Cheers,

John.

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