Bio is solar too, just not at all wave lengths . . .
> Most solar technologies are aimed at producing electricity,
> but a new class of solar chemical reactors aims to make liquid fuels from air, water, and sunshine.
With solar thermal - bio combinations the efficiency can be increased
by concentrating only the green light [the wavelength green] -- most
of the energy -- and using the white not falling on the collectors,
the red and maybe some blue for the bio.
. . . .
> As reported by Robert F. Service, Science magazine's resident green fuels
. . .
> the potential of solar
> thermochemical fuels. Positive benefits Include lowered carbon emissions, energy independence and
> that most elusive of qualities for alternate energy-scalability.
If it's scalable then we don't need the Mojave.
>The article describes several
> prototype projects, including on headed by Richard Diver, a solar engineer at Sandia National
> Laboratories:
>
> Inside the reactor sit 14 cobalt ferrite rings, made from a mixture of cobalt and iron oxide, or
> rust. Each ring is about 1/3 of a meter in diameter and rotates between two separate reaction
> chambers. Sunlight from the heliostat and the parabolic mirror is focused through a window in the
> reactor, heating the interior to as high as 1500°C. At that temperature, the flakes of iron oxide
> catalyst on the outside of each ring spit out oxygen molecules, which are vented to the outside
> (see figure, below). As the disks turn, they enter the second, 1100°C chamber, which is spiked with
> CO2 or water vapor from which the catalyst swipes oxygen atoms. This reaction generates the
> energetic gases (H2 or CO), which are collected, and restores the catalyst to its original
> composition, ready for another turn of the wheel.
>
> Basically, this process uses heat from the Sun and an iron oxide catalyst in the reactor to split
> either water or carbon dioxide (CO2), producing hydrogen gas or carbon monoxide. These chemicals
> can then be used as energy-rich feedstocks for making liquid fuels such as gasoline. Turning solar
> energy into liquid hydrocarbon fuels would be a great advantage, since that would reduce the need
> for imported oil while allowing the continued use of existing infrastructure-pipelines and filling
> stations.
>
> [diagram]
> Heat from concentrated sunlight converts a magnetite (Fe3O4) catalyst into wüstite (FeO) and
> oxygen. A second step swipes oxygen to restore the catalyst. Credit: Randy Montoya/Sandia.
>
> This all sounds very encouraging but there are a few problems, beginning with the fact that he
> process is not notably efficient.
> Researchers agree that a reasonable goal would be a reactor that
> converts 20% of incoming heat to fuel by 2020.
That's better than PV and almost 2/3rds of dish Stirling.
Saving energy from a generator requires a battery with high cost and
conversion inefficiencies.
It may beat dish Stirling in some stiuations.
> Better efficiency would have other payoffs as well.
> Most important, it could enable the use smaller collector mirrors, which account for roughly half
> the cost of current solar thermal systems.
Green [the wavelength] concentrators will need to be somewhat larger
than full spectrum.
> Even so, it will be a struggle to reduce fuel cost to
> less than $10 per gallon-certainly not competitive with current fossil fuel prices.
In other words, it'll be cost effective by 2012.
They need to get _moving_.
> Unfortunately, commercial plants capable of turning CO2 or water into liquid fuels are still likely
> to be 20 years away even with major funding support.
We need to get _moving_.
> A simpler version of the technology that can
> convert wood waste and other forms of biomass into syngas-a gaseous blend of carbon monoxide and
> hydrogen-is also being developed. Converting biomass to syngas requires only quickly heating the
> biomass in the presence of steam. Syngas can then be converted into gasoline using techniques that
> have been used for decades.
>
> This technology has been held back in the past because some of the biomass itself, or other fossil
> fuels, were needed to provide the heat to power the reaction. This lowered the effective yield,
> raised the price of the resulting fuel and, if fossil fuels were used, defeated the goal of
> reducing carbon emissions. Getting the heat from solar concentrators eliminates that heating cost
> and avoids generating excess CO2. How the initial cost of the solar concentrators affects the
> economics of the process remains to be seen.
There's a const. 40 - 55 mph wind in the Mojave so there is no way to
avoid a stout concentrator structure.
In other places it might not be so expensive.
. . .
> The green energy "visionaries" don't want to solve the world's energy problems in an
> ecologically responsible way, they want to destroy the entire industrialized world.
They think we can can everything and they may be right.
Bret Cahill
No Bret,
Producing 'heat' energy fuel is just some feel good goofy idea when
using virtually the same infrastructure that could generate electricity.
It is anything 'but' more efferent in any circumstance.
It makes as much sense as converting electricity to coal. Carnot would
roll in his grave...
The 20% figure came from the pro carbon article. Round trip battery
storage may lose 30% of the energy.
Dish Stirling will always be valuable simply because it's peak power
when you need it -- hot summer afternoons.
Bret Cahill
Why snip what I wrote? Either you are being purposefully obtuse or you
just don't get it.
Why did you snip what _I_ wrote about green [wavelength] thermal
collectors that transmit red for the alga?
You get maximum efficiency separating the light.
Bret Cahill
Finally we can get back to philosophy and qualia and stuff. What quale
is the light to the algae? And isn't it a bit presumptuous of us to
say "the algae is green" when the algae is rejecting the green light?
I mean, isn't the algae quale everything *but* green?
I'm just saying...
-tg
>>>>>> Researchers agree that a reasonable goal would be a reactor that
>>>>>> converts 20% of incoming heat to fuel by 2020.
>>
>>>>> That's better than PV and almost 2/3rds of dish Stirling.
I'd say clueless to start and obtuse so you don't have to admit you
don't get it.
Only idiots proffer opinions when numbers are all that matter.
Anyway you dodged the question:
Why did you snip what _I_ wrote about green [wavelength] thermal
collectors that transmit red for the alga?
Bret Cahill
And there you have it. Now apply real world numbers to your previous
claim, the one I left, the one you snipped.
>
> Anyway you dodged the question:
>
> Why did you snip what _I_ wrote about green [wavelength] thermal
> collectors that transmit red for the alga?
What does that have to do with the article and the claim you made?
Continue to obfuscate, I really don't care...
> > Why did you snip what _I_ wrote about green [wavelength] thermal
> > collectors that transmit red for the alga?
> What does that have to do with the article
The article was about combining two types of solar, bio + solar
thermal, to make liquid fuel.
Since the bio only needs red light, why not make the collector 20%
larger and use the green for the solar thermal and then use the
remaining light for the alge?
Bret Cahill
Yup. Exactly correct. Separating the PAR light from the other and using
the other to create electricity to run the pumps and such that are needed
to enhance algae growth and/or whatever is needed (motors to move the
parabolic collectors or PRISM that "tracks" the sun) makes perfect
sense. I never could find a way to convert all (or even part) of that
"other" spectrum to PAR. But I admit I am confused about the process
being described in the initial posts of this thread. It seems like a
replacement for photosynthesis, i.e. no algae needed.
--
"Senate rules don't trump the Constitution" -- http://GreaterVoice.org/60
As if this exotic infrastructure, that is not referenced in the article,
could be pulled from someone's ass.
You should both go back and read the lead article.
<http://theresilientearth.com/?q=content/solar-fuel-snake-oil-political-sabotage>
The 'biomass' is about feedstock for the process, it is _not_ produced
by the process.
And now that Bret has lead you on this tangent he further insulates
himself from acknowledging his gross error made earlier. Does that make
him look clever or you the mark?
What's so exotic about reflecting green and transmitting the rest?
You could also refract the light and _then_ reflect the components to
their targets.
Either we start pulling some stull out of our behinds or many will die
unnatural deaths.
Inventing ain't optional anymore.
> You should both go back and read the lead article.
> <http://theresilientearth.com/?q=content/solar-fuel-snake-oil-politica...>
>
> The 'biomass' is about feedstock for the process, it is _not_ produced
> by the process.
They're wasting precious desert land.
> And now that Bret has lead you on this tangent he further insulates
> himself from acknowledging his gross error made earlier.
What error?
Bret Cahill