From: Eugene Leitl (eugene@liposome.genebee.msu.su)
Date: Thu Dec 11 1997 - 04:50:18 MST
On Thu, 11 Dec 1997, Michael Lorrey wrote:
> > Statistics do not lie -- liers do statistics. I would be very interested
> > indeed to learn which exhausts a PV array emits during operation. It would
> ^^^^^^^^^
> PV pollution is a matter of the waste products of production. It takes
> quite a bit of pretty nasty stuff to make a solar cell.
I don't think thin-film PV arrays need to generate significantly more
waste than production of an equivalent floatglass surface. Silicon is
anyway not a good substrate for them. (There _is_ a reason for Silicon
Valley's massive environmental load).
If people refer to monocrystalline GaAs or Si arrays, that's their
problem. (One can also make diamond wafer PVs. Of course one could also
drive an ICU with diamond dust).
> Electric vehicles are, in total, around 45% efficient on average, while
There are motors exceeding 95%, controllers in >90% and fuel cells in >60%
range (theoretically, efficiency could also lie in >90% range). Regen
braking quantitatively reuses braking energy. No transmission is required
for a motor-in-wheel concept. Spike cache allows to reduce peak motor
performance significantly. Design synergies allows elimination of a large
number of dead weight, which allows drastical reduction of peak motor
performance. (Of course I am talking composite frames here. Why bothering
sticking modern tech into a rusting Packard hulk?)
> Internal Combustion vehicles are 18% efficient, on average. This is a
Fuel cell's exhaust is just carbon dioxide and water. It is physically
impossible to optimize ICUs into a clean burn.
> comparison of only the engine, power source, power train, and rolling
> and aerodynamic friction. When Power plant efficiencies are figured in,
> it comes out that EVs are on average 3 times more energy efficient, and,
> including power plant emissions, 33% cleaner than current IC technology.
> (of course, this fails to measure emissions of oil refineries, hint
> hint)
All this does not include a high-performance carbon-frame lithium-ion EV
charged of an PV array. Novel designs involve supercapacitors both for
main and spike storage.
> Once this is determined, one then evaluates the economic value of these
> benefits, and weighs them against the drawbacks, like decreased range,
> speed, safety, and user time wasted waiting for charging, and the higher
Due to synergistic effects the range is higher (at least twice range),
travelling speed is equivalent or higher, peak performance significantly
higher, safety significantly higher (there's a reason Formula I cars have
composite frames), recharging of a battery-swap EV (most EVs recharge
overnight or at work since used for commuting) or a fuel-cell vehicle
equal.
> cost to purchase a vehicle.
Costs are significantly higher. Should be somewhat cheaper, if mass
produced.
> Personally, I think that if all a driver needs a car for is to commute
> 50 miles or less each day (as is the case with 80% of American workers),
> then an EV makes sense. If one hopes to use a car for any recreational
> purposes, however, an EV is not a good idea. An EV may be a good choice
> for one vehicle in a two vehicle household for weekday carpooling.
Currently, yes. If their potential is properly developed, EV significantly
outperform modern ICEs in all respects. And if you really want hovercars,
you can always use microturbine arrays.
The reason why we don't have (fuelcell)EVs today are past and current
marketing decisions.
ciao,
'gene
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