"The Trucker"
verizon.net> wrote in message
news:pan.2008.08.22.08.09.34.756850@verizon.net...> On Thu, 21 Aug 2008 23:23:44 -0700, Rob Dekker wrote:
>
>>
>> "The Trucker"
verizon.net> wrote in message>>> 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.
Well, as long as night time electric rate is lower than daytime, there would
be no use to 'storing' electricity for the night. The other way around would
be smarter (you can actually make money with a grid storage system that
charges at low night rates and discharges during peak daytim rate).
Also, solar thermal electricity (daytime) will be mostly used for the
daytime peak. Peak electric use of air-conditioners typically coincides with
top-power of solar thermal plants.
Finally, with increase use of wind and solar, some grid-storage will likely
be needed any way, regardless of when cars are going to be charged exactly.
There is actually an interesting idea called V2G (Vehicle to Grid) which
allows (unused, plugged-in) vehicles to serve as part of a 'distributed grid
storage system'. Vehicle owners get paid to fill in peak demand with power
from their vehicle, and the utility gets a low-cost peak-demand leveling and
load balancing method. Software takes care of the details. Pretty cool !
http://en.wikipedia.org/wiki/V2G
> And I don't know if I
> believe the 95%% efficiency of the battery. That seems pretty high.
I think it's accurate for modern batteries (Li-ion and Zebra's and such),
but it may be 90%% too.
>
> 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.
>
Most numbers are rough estimates, so you even if grid-storage is better than
this, or not needed for night time (see above) then a +/- 20%% error in the
estimate (of 16X) seems fair. So let's say that algae oil is between 10 and
20X less efficient than solar thermal. That puts enormous cost constraints
on the algae plant, unless price of liquid fuel (oil) goes up another factor
of 10 or so. That, or the cost of algae plants needs to be 10-20X lower than
cost of solar thermal plants.
Incidentally (I hate to bring this up, since I know you hate the guts of his
findings, but) Dimitrov found exactly this : He estimated that algae oil
would be commercially viable (with current algae bioreactor designs) if oil
reaches $900/barrel or so.
I still hope that somebody would build a few algae pilot plants that are
indeed dirt-cheap. Plastic foil tubes or closed ponds or so.
>
.....
>> 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?
I don't know Trucker. I really don't see any short-term relief other than
conservation.
The only 'good' thing is that oil won't run out tomorrow.
Peak Oil was reached slowly (we creeped up 1-2%% annually, to current
85million barrels/day), will probably be stable for a couple of years and
then slowly decline. Maybe 1-2%% annually first, then faster later.
If we can 'conserve' our way through the first 10-15 years, then maybe
ultra-efficient series-hybrids, PHEVs and EVs can start to truely make a
difference in our consumption of oil. Maybe just enough to compensate for
the annual decline of oil supplies.
> 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.
I agree. These are probably going to be optimizing the ICE more and more and
move to series-hybrid, and move to batteries later. But city-busses and
school busses (diesels) will move to batteries very quickly, very soon
(within the next few years). Mark my words.
Airplanes will definitely not change to batteries any time soon, so there is
plenty market for biofuels for a long time to come.
>
> 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.
My daytime job is to make complex electronic systems easier to design, and
build.
I hope this will help further enhance telecommuting and tele presence.
Still, some meetings are simply better done face-to-face then
face-to-computer.
Also, am I the only one that feels that many people don't want to work at
home ?
I'm not sure if I'm out on a limb here, but maybe they simply feel more at
peace in their office rather than at home with constant interruptions from
pets and other house companions....
Either way, people will continue to travel to work and back. And here in the
US they really prefer to do that by car.
>
>>>> *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
>
http://GreaterVoice.org/extend
>
