On Thu, 21 Aug 2008 23:23:44 -0700, Rob Dekker wrote:
>
> "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%%.
There are some problems with this. The sun shines in the daytime and we
charge up our cars at night. That infers that the electrical energy must
be committed to some form of battery at the power company before I ever
get it at the house so as to charge up my car. And I don't know if I
believe the 95%% efficiency of the battery. That seems pretty high.
So taking into consideration the storage of the juice at the power plant
at 80%% efficiency I get an 11.5%% total. That is still 11 times better
than the current biofuels.
> 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).
So I am saying it will be 15 years before we will see any big impact from
electric vehicles. And what they hell do we do between now and then? And
the other thing is that I can't see my diesel 18 wheeler with an electric
motor and a battery or a farmers combine or an airplane.
Why do people drive downtown and sit at a desk? We have lots of vacant
houses in the suburbs and lots of broadband capacity and most of these
people sit at a keyboard and monitor all day. It may be that the white
collar people on the top floor come to their senses and start allowing the
worker bees to stay at the house. That would be a good way to address GW
and peak oil and oil dependency and prices. But the vested interests will
not give up that economic rent.
>>> *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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