Jaques d'Alltrades wrote:

The message
from The Natural Philosopher contains these words:


And just how do you think electricity to charge the batteries is
produced? With a loss approaching 30% at every stage: thermal value of
fuel for power station to power delivered at charger (taking in power
loss in transmission lines), charging the accumulator, discharging the
accumulator all taken into account, the net result is a great deal more
pollution to propel your so-called clean electric vehicle.


Well first of all, because it isn't 30% at every stage.


Thermal efficiency of a modern power station is up to 65% - more if you
can use the waste heat to e.g. heat water for the neighborhood.


Elecricity generators and motors can achieve over 90%, and transformers
etc are typically around the 95% plus mark.


At optimum levels, and only the very best and most expensive - and how
many manufacturers use that sort of quality of component?



Its not that hard. Efficiency is mostly about using bigger dimensions of
wire and iron for a given power: Wire and iron is not expensive, and in
power generation it is sensible to spend a few extra quid to save a few
thousand a year on fuel costs.

The tackiest electric motors I have are no worse than 50% efficient -
better than an IC engine.



I am not sure on distribution losses. Theortecically those can be as low
as you like, by use of fatter or supercinducting cables.


Superconducting cables can be as low as zero (for 99,99% pure niobium at
liquid nitrogen temperatures), but the environmental cost of keeping
them in the superconductor range would far outweigh the gain.


My extensive experience of charge/dishcarge of secondary cells suggests
that 90% convesrion or better ins not uncommon.


The big things in favour of all electric cars tho are


(i) the initial electricity generation can be done by many different
things - from windmills to nuclear power stations, as well as burning
non fossil fuels (biomass)


But burning hydrogen, or even a hydrocarbon in an internal combustion
engine will still be less polluting.



Well no it isn't, because it produces water vapour at the least in the
car, secondly the hydrogen has to be produced - from electricity.

If you look at the overall energy equations, you use more to generate
hydrogen from electricity than to generate the electricty.

Also, as I said, distributing hyrogen requires a whole new
infrastructure, Its not safe to do it in a simple tanker. Nor can it
simply be stored in underground tanks.




(ii) its a lot easier to scrub atmospheric pollutants from a power
station flue than from a car exhaust. That doesn';t affect the hydrigen
versus electric car argment tho.


Then what happens to the scrubbed-out pollutants, I wonder?


Well, one of the ways of getting rid of Co2 from burining e.g. oil that
has nbeen proposed, is to put it back underground.

Atomically, pollution is a zero sum game. We had all that carbon in teh
ground, and no one worried. Now its in the air and we do. Its used up
atmospheric oxyhgen (and hydrogen does that to make water) and so
depending on wthere the lower oxygen or higher CO2 is the problem, you
can e.g. make carbonates and bury em.

Essentially scruvbbing power stations flues makes thungs like sulphuric
acid - useful in luquid form, bad in teh air - and nitric acid.

This is BETTER than buring in a car where all teh issues raised make it
innecicient and expensive to remove, but not ideal.

I think we need to look at this iin a sensible perespective.

There is nothing wrouong witha hydrogen car, if hydrogen were just lying
around waiting to be burned, except that eventual;ly you would use up
all teh ocygen in teh air. At least with burning carbomn, we know rthat
plants eat teh stuff and release oxygen...


Hydrogen and electric produce on teh one hand just water, and on the
other hand nothing, as waste products, used as fuel, at the point of usage.

BUT when it comes to teh energy analysis of producing electricity and
hydrogen, and distributing them, as far as I know the only way to mass
produce hydrogen is by electrolysis.


So the hydrogen has electricity as its starting point anyway, and cannot
be 100% efficient in generation.

And te storage of hydrogen is non trivial.

The only reason hydrogen is being considered is because it can be burned
in not-too-different- cars. The car industry is amongst the stupidest
and most conservative there is. They are only thinkning of teh least
investment to produce the next lump of tin that will 'meet regulations'.

WE I hope, are talking about saving energy, and lowering global pollution.

When you look at it, actually the tidiest thing is nuclear. Produces no
pollution at all, apart from warm water, apart from that niggling litle
problem of radioactive spent fuel and things what got near it. Crack
that one and you are away...it may be that in the end we have to acept
it as the lesser of many evils.


And
incedentally, scrubbing pollutants from that volume of exhaust gas
requires a gigantic investment in plant and running power, and it's my
belief that that investment will never 'repay' the amount of
energy/pollution required for its construction.


Well, that depends on legislation doesn't it? In the micro scale. On the
macro scale saving the planet might be worth it?

If for example you calculted that teh loss of property and erosion of
coastlines diue to gl;obal warming was costing the inusrance industry
say 50 nubillion a year, then teh insurance companies might decide to
fund the costs themselves...out of sheer self interest. Or the
givernments decide that the taxpayer should bear the cost, and get it
back in reduced insurance premiunms. Etc.






(iii) we already have an electrical distribution system that has huge
off peak energy availability. And that is precsiely when we would be
charging our cars up. Essentally tow electrckettles overnight is all it
takes power wise, to get a full days motoring (unless you intend to
drive to scoitland, in which case the electric car uis stll not able to
cut teh mustard, although it is feasible to fully rechage current cells
in about one hour at e.g. a specially equipped 'service station'


I've said it before in another forum: if you bothered to use a
spellchecker, your posts would be readable. It takes too long to reply
yo one of your posts point-by-point.



That is the neatest way of ducking out of a losing argument I have ever
seen.


/rest of it snipped. Life is too short/

And thread killed.