"The Trucker"
verizon.net> wrote in message news:pan.2008.08.19.05.31.04.476518@verizon.net...> On Mon, 18 Aug 2008 10:04:46 -0700, nada wrote:
.........
>> Thank you Bob, a breath of sanity in an inane discussion and upsurd
>> claims. Seems some people grab onto anything and think it's the "next
>> best thing".
>
> So you claim 20%% efficiency? IF that is true then biofuel generation at
> 5%% efficiency is a much better solution than photovoltaics and electric
> cars. Liquid fuel is a very good battery.
Yes and no.
Liquid fuel has great energy density, but is sucks in cycle efficiency.
5%% efficiency is about as good as it gets to go from sunlight to biofuel (using algae).
But the ICE that burns the fuel then has 20%% efficiency before the vehicle's wheels are turning.
That brings overall efficiency of sunlight->turning wheels to about 1%% for the biofuel path.
Solar thermal has 20%% efficiency from sunlight->grid-electricity. Grid electricity to turning wheels via a PHEV (or EV) is done with
around 80%% overall (counting the efficiencies in power transmission/distribution (~90%%), battery cycle efficiency (95%%), and
electric motor in the vehicle (95%%).
That brings overall efficiency of sunlight->turning wheels to 16%%.
That's a 16x efficiency difference between solar thermal and algae biofuels.
That's gonna be hard to make up in plant cost (algae plant must be 16X cheaper than solar thermal plant).
So I think that biofuels (like algae oil) will be great for aviation (where the superior energy density of liquid fuel is
necessary), but will not make much of an impact for ground-based transportation.
That still leaves an increadably big market for biofuels, since aviation (jet) fuel constitutes some 10%% of all oil use in the world
(or something close to that).
Incidentally, KLM signed an agreement with some algae company in Europe to check out if algae oil can be as substitute for jet fuel.
So the market is looking in the right direction.
>
>> *Solar is making SMALL inroads into electrical generation. NONE of it
>> is being marketed *at all* for transportation and all it is very
>> expensive even if 'the prices come down'.
>
> Biofuel is solar.
>
>> *Engines that get 200 miles...blah, blah. It's not the engine (really
>> a motor) but electrical storage that is the big, big, big issue and
>> only some inroads have been made here. I think they should invest 10
>> times the amount of money to develop a serious battery/storage
>> device...it could well mean the future and I hope it does.
>
> It won't make any difference how much you spend. If it ain't there then
> looking harder won't find it. It may be that biotechnology is a better
> place to spend.
>
There is plenty of possibility to make batteries better. Even the current ones will do fine for most PHEV applications (100 mile
electric range).
What is lacking is a vehicle 'platform' where these batteries can be used. Almost all current production cars have ICEs, and are
designed around ICEs.
What we need is series hybrids. Lots of them.... THEN the age of the electric-grid-charged vehicle battery will finally take off,
and start to make a difference in the world (in reduced oil consumption).
>> *I agree with Rod...nuclear is the future.
>
> The question is what to do in the next 20 years. It may be that liquid
> fuels and the ICE are good for another 50 years. That does not say
> nuclear isn't the right thing for every other energy need. I just can't
> imagine a commercial airliner with a battery. A rubber band maybe.
We probably will just use less liquid fuel.
Ride more bicycle and such.
>
> --
> "I know no safe depository of the ultimate powers
> of society but the people themselves; and
> if we think them not enlightened enough to
> exercise their control with a wholesome
> discretion, the remedy is not to take it from
> them, but to inform their discretion by
> education." - Thomas Jefferson
>
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>
