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.

Bob Hobden wrote:



Wrong. The hydrogen has to be made. An innefficent process that burns as
much, if not more, fossil fuel than any other form of transport.


Not quite true, fuel cells don't burn anything and Hydrogen can be obtained
from the usual sources, LPG, Petrol, Natural Gas, methane, methanol etc by
the use of a reformer which is significantly more efficient and less
polluting than when the same fuel is burnt.


Fuel cells do chemically transform fuels into waste products. The fact
that its at a temperature where no flame is produced doesn't inviolate
the chemistry. Perhaps I should have placed "burn" in inverted commas...

LPG, Natural Gas, Methane - these are all fossil fuels that require the
bound carbon to be tirned into usually CO2 to release stored energy. It
makes no odds how its done.


Al you are gaining is a slight improvement in efficiency.



Electricity produced by/from Fuel Cells (probably the Molten Carbonate type)
which will significantly improve the efficiency of fossil fuel Power
Stations. Some cells are already in use for small scale static power
stations.



That is a sound idea. I have no argument against fuel cells used in
static power generation as a more efficient way of making electricity. I
just think that hydrogen, and mobile fuel cells, is in teh first case
too expensive, and in te second place not a long term solution.

We need to concentrate on

(i) efficient and low pollution electrity generatin

and

(ii) electric cars to use it using existing (enhanced) infrastructure and

(iii) not using cars at all.




I understand it would take a battery of solar cells the size of 25% of the
UK to power the whole world from sunlight, especially in a desert area with
high sunlight levels. Such electricity could be used directly in vehicles
with normal batteries or to produce Hydrogen from water to power fuel cells
( which are batteries too).


Excellent idea if it were feasible. Solar cells are alarmingly
inefficient and expensive though. I think you will find that pounbd for
pound, its ceaper to e.g. grow and coppice willow, and burn it or turn
it into methanol, than cover the same acreage of ground with solar
cells, AND get more energy out of it too.





Much more efficient to burn the hydrogen in a reciprocating (or rotary)
engine than to convert it through a fuel cell to run an electric motor,
though electrically propelled vehicles do have the potential to convert
the slowing down process back into usable power.


ever heard of regenerative braking, had it on coaches for
years and there are other more recent developments in this area relating to
normal cars too.


That is what I was describing? Not sure why you appearded to contradict
whilst actually saying the same thing..:-)




However the real simple answer that dare not speak its name, is 'why the
**** do we need to go anywhere at all' and the answer is, mostly we

don't.

Lets face it most of what we do could be done in front of a console from
home, if we had to.


Unlike you I don't want to spend my life in a prison, even a very nice one.


No one said you had to. I merely questin teh need to :-

(i) take the car out to run teh klids 2 miles to school
(ii) take th car out to get to the staion to got to work
e(iii) take the car out again to do teh shopping
(iv) take the car out to pick teh kids up from school again.
(v) take the car out at teh weekend to drive round 14 different sheds
only to find that the thing you wanted could be got from Screwfix online
without using teh car at all.

Knock out all thise unneccesary journeys, and taking the car out to
actually enjoy your friends company, go down the pub, go out to a show -
well the roads are now clearer, speeds aare higher, stress and power use
is lower, and the world is not so polluted.






And I suppose the goods we need will be delivered through the telephone
wires too? When I go shopping I visit a number of outlets. I can see
what I want to buy, and reject what had interested me from its
description. I generally share a car with a friend's family anyway,
doubling the efficiency of a trip. Well, since he has a family, more
than doubling it.

Sorry, your dream will never catch on.


That's not a dream it's a nightmare.



Its not. Its how it will be. We spend a huge amount of our lives driving
to no real benefit and for no real reason iher than thats the way its
done. No one says we stop doing it entirely, just stop doing 75% of it.

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.

Bob Hobden wrote:



Wrong. The hydrogen has to be made. An innefficent process that burns as
much, if not more, fossil fuel than any other form of transport.


Not quite true, fuel cells don't burn anything and Hydrogen can be obtained
from the usual sources, LPG, Petrol, Natural Gas, methane, methanol etc by
the use of a reformer which is significantly more efficient and less
polluting than when the same fuel is burnt.


Fuel cells do chemically transform fuels into waste products. The fact
that its at a temperature where no flame is produced doesn't inviolate
the chemistry. Perhaps I should have placed "burn" in inverted commas...

LPG, Natural Gas, Methane - these are all fossil fuels that require the
bound carbon to be tirned into usually CO2 to release stored energy. It
makes no odds how its done.


Al you are gaining is a slight improvement in efficiency.



Electricity produced by/from Fuel Cells (probably the Molten Carbonate type)
which will significantly improve the efficiency of fossil fuel Power
Stations. Some cells are already in use for small scale static power
stations.



That is a sound idea. I have no argument against fuel cells used in
static power generation as a more efficient way of making electricity. I
just think that hydrogen, and mobile fuel cells, is in teh first case
too expensive, and in te second place not a long term solution.

We need to concentrate on

(i) efficient and low pollution electrity generatin

and

(ii) electric cars to use it using existing (enhanced) infrastructure and

(iii) not using cars at all.




I understand it would take a battery of solar cells the size of 25% of the
UK to power the whole world from sunlight, especially in a desert area with
high sunlight levels. Such electricity could be used directly in vehicles
with normal batteries or to produce Hydrogen from water to power fuel cells
( which are batteries too).


Excellent idea if it were feasible. Solar cells are alarmingly
inefficient and expensive though. I think you will find that pounbd for
pound, its ceaper to e.g. grow and coppice willow, and burn it or turn
it into methanol, than cover the same acreage of ground with solar
cells, AND get more energy out of it too.





Much more efficient to burn the hydrogen in a reciprocating (or rotary)
engine than to convert it through a fuel cell to run an electric motor,
though electrically propelled vehicles do have the potential to convert
the slowing down process back into usable power.


ever heard of regenerative braking, had it on coaches for
years and there are other more recent developments in this area relating to
normal cars too.


That is what I was describing? Not sure why you appearded to contradict
whilst actually saying the same thing..:-)




However the real simple answer that dare not speak its name, is 'why the
**** do we need to go anywhere at all' and the answer is, mostly we

don't.

Lets face it most of what we do could be done in front of a console from
home, if we had to.


Unlike you I don't want to spend my life in a prison, even a very nice one.


No one said you had to. I merely questin teh need to :-

(i) take the car out to run teh klids 2 miles to school
(ii) take th car out to get to the staion to got to work
e(iii) take the car out again to do teh shopping
(iv) take the car out to pick teh kids up from school again.
(v) take the car out at teh weekend to drive round 14 different sheds
only to find that the thing you wanted could be got from Screwfix online
without using teh car at all.

Knock out all thise unneccesary journeys, and taking the car out to
actually enjoy your friends company, go down the pub, go out to a show -
well the roads are now clearer, speeds aare higher, stress and power use
is lower, and the world is not so polluted.






And I suppose the goods we need will be delivered through the telephone
wires too? When I go shopping I visit a number of outlets. I can see
what I want to buy, and reject what had interested me from its
description. I generally share a car with a friend's family anyway,
doubling the efficiency of a trip. Well, since he has a family, more
than doubling it.

Sorry, your dream will never catch on.


That's not a dream it's a nightmare.



Its not. Its how it will be. We spend a huge amount of our lives driving
to no real benefit and for no real reason iher than thats the way its
done. No one says we stop doing it entirely, just stop doing 75% of it.

Bob Hobden wrote:


No it's not! everything I've written above is true. Ignoring the data, if
you simply look at the petrol consumption of ,say, a 1600cc car 30 years ago
( about 26mpg)


My 30 year old triumph spitfire in stock form at leagal speeds would do
better than 40mpg. It didnt after I had tuned it up to 110bhp,
admittedly :-) BMC A and B series engines were also capable of well in
excess of 40mpg.

Ford 1600 engines were alwasy carp its true, but at least you coudl
tweak em up to ridiculous power easily. Fuel injection has been the
greatest benefit.


and compare it with a modern engine ( about 40+mpg) you will
find significant improvements in efficiency which also does relate to the
pollution produced, even without catalists in the exhaust system. The fact
that these modern cars also have much more inside them consuming power
proves my point further.


And elecric fans, to redice power loss on cooling fans.

However, we now use fatter tyres (more rolling resistance) and travel
fatser, and in general spend so much time in congestion that average
fuel consumption is in fact worse.




Probably due to the significant rise in the use of Diesel engines (in cars)
which produce lots of small particules (soot) which get into our lungs and
clog them up. Particle Traps are on their way to cure this problem, I think
it's one of the French manufacturers that is already installing them. I too
have developed Asthma in the last 10 years.


I totally agree on that one. Catalytic convertors work extremely well in
places like califirnia, where temperatures are higher and the big
problem was unburnt hydrocarbons producing smog.

They arer wuite good in countries where average jorneys are long enough
for them to get up to temp as well.

Not so here, and the stuff in fuel now to repalce lead, is highly toxic
and carcinogenic ...diesels are disgusting. They nee filters and
catalysts too.




Nobody has pointed out a flaw at all, to me they just show they don't know
about Fuel Cells, their possibilities, uses and how fast the technology is
advancing so there is little chance of agreement on this topic.



No, ther are more issues at stake than lung irritation. On the global
warming front, you are still using fossil fuels with fuel cells.

I attended a 'clean energy' conference some years back attended by
represntatives from teh finacial, oil, and automotive industries.

The oil men want fuel cells, because it menas they still get to sell oil.

The automotive men wanted hydrigen, because it meant they could still
sell cars.

The financial lot, shook their heads and walked out early. "If its sll
tio be enfirced by legistlation, the government will ensure its barely
profitable"

I asked the one question - "what is the most energy efficient way of
transporting a ton overland" "Railways" muttered someone from the
back...and that was it.

Not one preson in that room was actually interested in what was the
ultimately sanest transport policy. "Not my problem".

All these latrenatives are being touted by groupps with vested interests
in preserving their installed base of manufacturing capability.

Ther IS no installed base of electric ras manufactures: Up till a couple
of years ago there wasn't a suitable battery. There is now.







Oh, and with power stations also going over to the use of Fuel Cells
pollution from them will reduce too. :-)



No argument there.
And windmills, and tide power and hydroelectric and burning biomass and
burning rubbish - especially paper, and CHP and and and...a million ways
to make power that cannot be put in a car.

As you may know, I have a little hobby. Flying electric model aircraft.
Up to tow years ago there was no way to even approach the power and
energy densities of a tank of fuel. There is now. And its tipped the
balance so that applied to cars, it comes out damn near equal overall in
terms of power and range to weight of a tank of petrol and what is
needed to make it turn the wheels..

I can buy all I need to use this technology NOW.

I can't buy a fuel cell.

I am sure that I weill be able to buy both in a few years time, BUT with
fuel cells still using FUEL I am convinced teh electric will win ot,
because you can generate electricity inso many more ways than "burning"
FUEL.

IMM wrote:


Because there have been minor improvements in a flawed highly inefficient
piston engine design over the past 30 years, you appear to think this
exonerates the internal combustion engine, or it is efficient or clean or
something. It is NOT.

The engine it at the end of its lifespan, it should have gone 50 years ago.

snip



As I mentioned in another post, according to MIT the fuel cell is not viable
yet for vehicles, which are the world's worst polluters.

Far more efficient Rotary and Stirling diesel and petrol units appear the
best options to fill the gap. The Stirling is external combustion, which is
much a clean on the burn. Even the Rev Tec Aussie engine, a piston engine,
improves thermal efficiency from 25% to over 50%.


What you have failed to realise, is that even these are only stopgaps too.

At the very best, a fuel BURNING engine delivers only 60%

efficiency - maybe a little more. The rest is waste heat.


If you had goine to a snotty uni, where the theory is taught, you would
understand that any heat engine - and all the above are heat engines -
has its efficiency dictated by the ratio of the temperature of burn to
the echaust temperature. Especially as that is why a 'condensing boiler'
is built the way it is.

The big picture is about energy conservation, especially in terms of
waste heat, and the irreversible (in the short to medium term) problem
if taking fossilised carbon out of the ground and pumping it into the air.

To solve that you need to

- use less.
- burn plants you grew last year.
- generate power by means that don't generate waste heat OR
- use waste heat to replace the use of fuel elsewhere (CHP)

Use of the engines described does not solve any of these apart from, in
a minor way, the first.

Fuel cells can solve many of the above, but in the end. electricity is
bets because it generates very little waste heat when used to generate
mechanial motion.

The issues then become how to generate electricity without using fossil
fuel and/or heat engines. Feul cells are not heat engines, but usually
use fossil fuel. Nuclear power doesn't use fossil fuel, but does use a
heat engine. windmills do neither, but are ugly, of variable power, and
woefully inefficient in terms of space used. Water and wave power does
neither, but is localised as to its applicability. solar cells are even
ore woefully inneficient, but there mat be better technology coming..
burning domestc rubbish and biomass is good as it doesn't use (much)
fossil fuel - i.,e. it's more or less carbon neutral, but it does tend
to need treatement to reduce pollution of toxic flue gasses.

There is no easy answer. But simply slightly better heat engines
burining fossil fuils are almost the worst of all possible answers.

IMM wrote:


Because there have been minor improvements in a flawed highly inefficient
piston engine design over the past 30 years, you appear to think this
exonerates the internal combustion engine, or it is efficient or clean or
something. It is NOT.

The engine it at the end of its lifespan, it should have gone 50 years ago.

snip



As I mentioned in another post, according to MIT the fuel cell is not viable
yet for vehicles, which are the world's worst polluters.

Far more efficient Rotary and Stirling diesel and petrol units appear the
best options to fill the gap. The Stirling is external combustion, which is
much a clean on the burn. Even the Rev Tec Aussie engine, a piston engine,
improves thermal efficiency from 25% to over 50%.


What you have failed to realise, is that even these are only stopgaps too.

At the very best, a fuel BURNING engine delivers only 60%

efficiency - maybe a little more. The rest is waste heat.


If you had goine to a snotty uni, where the theory is taught, you would
understand that any heat engine - and all the above are heat engines -
has its efficiency dictated by the ratio of the temperature of burn to
the echaust temperature. Especially as that is why a 'condensing boiler'
is built the way it is.

The big picture is about energy conservation, especially in terms of
waste heat, and the irreversible (in the short to medium term) problem
if taking fossilised carbon out of the ground and pumping it into the air.

To solve that you need to

- use less.
- burn plants you grew last year.
- generate power by means that don't generate waste heat OR
- use waste heat to replace the use of fuel elsewhere (CHP)

Use of the engines described does not solve any of these apart from, in
a minor way, the first.

Fuel cells can solve many of the above, but in the end. electricity is
bets because it generates very little waste heat when used to generate
mechanial motion.

The issues then become how to generate electricity without using fossil
fuel and/or heat engines. Feul cells are not heat engines, but usually
use fossil fuel. Nuclear power doesn't use fossil fuel, but does use a
heat engine. windmills do neither, but are ugly, of variable power, and
woefully inefficient in terms of space used. Water and wave power does
neither, but is localised as to its applicability. solar cells are even
ore woefully inneficient, but there mat be better technology coming..
burning domestc rubbish and biomass is good as it doesn't use (much)
fossil fuel - i.,e. it's more or less carbon neutral, but it does tend
to need treatement to reduce pollution of toxic flue gasses.

There is no easy answer. But simply slightly better heat engines
burining fossil fuils are almost the worst of all possible answers.

Jaques d'Alltrades wrote:

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.
^^

Bwahahaha! Ha!!

--
Grunff

In article ,
Nick Maclaren wrote:
Worse, they work only after
the engine has warmed up (about 5 miles) and the average trip in the
UK is about 3 miles.

This may have been true when they were first introduced, but modern types
work much more quickly. FWIW, a cat doesn't rely on the engine
temperature, but that of the exhaust gasses which are largely independent
of this.

--
*Ham and Eggs: Just a day's work for a chicken, but a lifetime commitment

Dave Plowman London SW 12
RIP Acorn

"Bob Hobden" wrote in message
...

"Nick wrote in message after me .
.
The laws on vehicle pollution continue to get tougher and tougher and
the
manufacturers have had to comply to continue to sell vehicles. There
has
been massive strides in reducing pollution from cars, per mile
travelled.
Catalytic Converters, Electronic Engine Control, lean burn engines, two
stage ignition, direct petrol injection, particle traps etc with more
to
come. We are significantly reducing overall pollution figures despite a
massive increase in vehicles, now all we need to do is get rid of all
those
old polluting buses.

I suggest that you take the effort to find out the facts behind the
government and motor lobby propaganda. That is completely untrue.

No it's not! everything I've written above is true. Ignoring the data, if
you simply look at the petrol consumption of ,say, a 1600cc car 30 years
ago
( about 26mpg) and compare it with a modern engine ( about 40+mpg) you
will
find significant improvements in efficiency which also does relate to the
pollution produced, even without catalists in the exhaust system. The fact
that these modern cars also have much more inside them consuming power
proves my point further.
.

2) Catalytic converters virtually eliminate carbon monoxide, but
increase the amount of nitrogen oxides. Worse, they work only after
the engine has warmed up (about 5 miles) and the average trip in the
UK is about 3 miles. Also, they don't work at all well when the engine
is idling (see (1). The reason that they "reduce pollution" is the
the government is very careful to measure only what they do reduce.

I will give you that an INCIDENTAL effect has been the removal of lead
and sulphur but, as someone with breathing problems, I can witness that
pollution for a given amount of traffic is getting worse.

Probably due to the significant rise in the use of Diesel engines (in
cars)
which produce lots of small particules (soot) which get into our lungs and
clog them up. Particle Traps are on their way to cure this problem, I
think
it's one of the French manufacturers that is already installing them. I
too
have developed Asthma in the last 10 years.


3) The various regulations have the effect of increasing the weight
of vehicles, discouraging more economical two-wheeled transport (both
motorcycles and bicycles, ridden on the road). I believe that it would
now be cheaper for me to get a HGV licence than a motorcycle one, and I
am a very "low risk" person. And cycling is now finished, as a form of
medium-distance commuting (3-10 miles), and that is DIRECTLY due to the
changes in regulations and attitudes of the "powers that be."

Other people have pointed out the errors in your "pollution-free" car
theory. All it does is move the pollution from the suburbs to the
power station, though I agree that doing so COULD be used to reduce
pollution. I know of no plans that any government has, and definitely
not the UK, to do so.


Nobody has pointed out a flaw at all, to me they just show they don't know
about Fuel Cells, their possibilities, uses and how fast the technology is
advancing so there is little chance of agreement on this topic.

I have been reading about the immense progress being made in fuel cell
technology for more than twenty years now. Why are they not yet in daily
use in every household?

Oh, and with power stations also going over to the use of Fuel Cells
pollution from them will reduce too. :-)

I have read a report one experimental fuel cell unit installed in Holland,
where it was mentioned that "At the point of shutdown, the unit was also
sustaining a power generating efficiency of more than 46 percent, well above
a conventional combustion-based power plant that typically generates
electricity at efficiencies of 33 to 35 percent".

That does not sit well with whoever it was who recently said something about
conventional power stations operating at 60%.

Franz

"Bob Hobden" wrote in message
...

[snip]

Much more efficient to burn the hydrogen in a reciprocating (or rotary)
engine than to convert it through a fuel cell to run an electric motor,
though electrically propelled vehicles do have the potential to convert
the slowing down process back into usable power.

Totally wrong, and ever heard of regenerative braking,

Evidently he had, as evinced in the paragraph you described as "totally
wrong".

[snip]

Franz

Dave Plowman wrote:

In article ,
Nick Maclaren wrote:

Worse, they work only after
the engine has warmed up (about 5 miles) and the average trip in the
UK is about 3 miles.


This may have been true when they were first introduced, but modern types
work much more quickly. FWIW, a cat doesn't rely on the engine
temperature, but that of the exhaust gasses which are largely independent
of this.



Cat still takes a mile or two to get hot tho.
Engine may take longer.

During that time the engine will be running very rich, and the cat will
allow huge amounts of unburnt fuel to spew out.

When I reverse the car out first thing, the exhaust STINKS of benzene
and other aromatics.

Dave Plowman wrote:

In article ,
Nick Maclaren wrote:

Worse, they work only after
the engine has warmed up (about 5 miles) and the average trip in the
UK is about 3 miles.


This may have been true when they were first introduced, but modern types
work much more quickly. FWIW, a cat doesn't rely on the engine
temperature, but that of the exhaust gasses which are largely independent
of this.



Cat still takes a mile or two to get hot tho.
Engine may take longer.

During that time the engine will be running very rich, and the cat will
allow huge amounts of unburnt fuel to spew out.

When I reverse the car out first thing, the exhaust STINKS of benzene
and other aromatics.

Dave Plowman wrote:

In article ,
Nick Maclaren wrote:

Worse, they work only after
the engine has warmed up (about 5 miles) and the average trip in the
UK is about 3 miles.


This may have been true when they were first introduced, but modern types
work much more quickly. FWIW, a cat doesn't rely on the engine
temperature, but that of the exhaust gasses which are largely independent
of this.



Cat still takes a mile or two to get hot tho.
Engine may take longer.

During that time the engine will be running very rich, and the cat will
allow huge amounts of unburnt fuel to spew out.

When I reverse the car out first thing, the exhaust STINKS of benzene
and other aromatics.

Franz Heymann wrote:



I have read a report one experimental fuel cell unit installed in Holland,
where it was mentioned that "At the point of shutdown, the unit was also
sustaining a power generating efficiency of more than 46 percent, well above
a conventional combustion-based power plant that typically generates
electricity at efficiencies of 33 to 35 percent".


That is typical of an old station running coal or gas, built to 60's
standards. Noit a modern set.



That does not sit well with whoever it was who recently said something about
conventional power stations operating at 60%.



Depends on what you mean by conventional.

The key to efficiency is getting your working fluids temperature and
pressure way up, and the final exhaust way down.

Steam turbines with ultra superheated steam going through multistage
turbines with condensors on the back end to get the back end temp way
down will do better than 50%. Gas turbines with extremely high
combustion temperatures, whose exhaust then heats water to drive a steam
turbine, do even better. If the coolant water at around 40-60C is then
fed to housing next door for heating purposes...you are getting up
towards 75-80% usage of thermal energy released.

And the last little bit goes to help you farm fish in the cooling tanks :-)

So, two points

- in an overall energy and fuel conservation analysis, efficiency is not
the primary problem. If you can use waste heat to save heating oil being
burnt - example, build a bakery next door and use the heat to run the
proving process, and bake bread at the edge of the furnace, or use waste
heat to heat greenhouses to grow vegetables, or to farm fish or whatever
- then you have an *ovearall* more efficient system anyway.

- in an overall carbon neutral scenario, you want to reduce the
conversion BY ANY MEANS of fossil fuel to carbon dioxide. I am not sure
what fuel cells produce, but the carbon has to end up somewhere. If they
are running on fossil fuels they don't really solve the problem. Whereas
burning waste paper in a combined heat/power set can be extremely
inefficient, as long as the heat ends up reducing fossil fuel usage and
generateing SOME power. Because paper comes from carbon that has been
taken OUT of the air by trees.

The trouble is that neither the governments nor the power industry has
any real incentive to either do the OVERALL analsysis, nor to embark on
co-operative projects to utilise e.g. waste heat.


If someone could only come up with a plant that I simply stuffed full of
junk-mail and which heated my house, generated most of my electricity,
and allowed me to run a few pipes rund the garden to grow vegetables in
winter from....at similar cost to an oil boiler...





Franz