Op-ed intro: Solar cells are probably NOT going to be the real future of
cost-effective solar energy, sorry to say. But there is still light at
the end of the tunnel, so to speak.
Despite Michel's mention of the always "glowing" press releases from a
particular company, there are still cynics in Silicon valley who contend
that Nanosolar could end up being closer to scam than to major player.
Caveat emptor (for the tech stock investor).
OTOH - there is solid good news and a brighter side to solar, so to
speak. This is a hybrid process for the grid level. Such a hybrid system
will allow cheap fuel like coal to be burned, but with far less
environmental impact, since solar will be used as both a remedial fix,
and for added energy. There is even the possibility of CO2 serving as an
"energy carrier" of sorts, for solar conversion.
Yes, this is not the ideal solution, as it might be implemented to only
reduce, and not eliminate CO2 -- and yes, it could be more of a stopgap
measure; but as a practical matter, that is precisely what is most
needed in today's real-world - i.e. a cost effective alternative to
unabated global warming due to coal burning (especially in China)... in
order to at least "buy time" for permanent solutions.
The idea is that the exhaust from a coal plant would be "filtered" by a
selective membrane (the Branson membrane) in order to concentrate the
larger molecule CO2 - and to immediately return the nitrogen to the
atmosphere.
At this stage, two of the three possible alternatives are grim. The CO2
could either be pumped into the ground (brain-dead), or the into oceans
(logistic problem with toxic side effects) or into algae ponds (fabulous
solution if you have enough flat land and water).
Given that many grid power plants burning coal or methane do not have
good siting for algae-culture, there is a fourth and newer alternative,
which involves getting the sun involved, as with algae -- but requiring
a much smaller footprint - a mirrored solar collector array which can
actually be sited above or close to the coal-fired plant.
At least that's the theory. A group at Sandia National Labs has carried
out proof of principle demonstrations of a device which uses solar to
convert CO2 into CO. Since CO is itself an excellent fuel, especially
for turbines, this sounds rather obvious in retrospect ... except for
the small fact that almost no one believed, prior to this, that the
bottom-line economics were worthwhile.
In addition to a (potential) continuous cycle of reburning (i.e. total
carbon neutrality) - carbon monoxide could also be used to make hydrogen
(using a water-shift process) or serve as a building block to synthesize
a liquid fuel, even gasoline or plastics. The Sandia team is building a
prototype reactor which will be ready for testing by summer 2008. "It's
95 percent built".
Here is how the process is contemplated:
http://www.sandia.gov/news/resources/releases/2007/sunshine.html
This is good news because, in theory, CO can be used as fuel - over and
over again - if and only if- the economics of using solar to reduce the
dioxide is better than alternatives: solar cells, for instance. It will
be interesting to see how the numbers compare to the cheapest printed
solar panels. In general, mirrors or Fresnel lens offer a gigantic cost
advantage to solar cells.
Although many casual observers seem to be enamored with the newer
concepts (ink printing) in solar panels, even the cheapest will be
terribly expensive, when actually installed, compared to other potential
solutions - and as mentioned by Michael, there are raw-materials
shortages which may never be solved.
Not to mention the level of fraud - and pump-and-dump stock scams in the
solar cell industry is becoming alarming... very reminiscent of the
situation with fuel-cells a few years ago.
In the once-bitten, twice shy department: look at the Fuel Cell industry
today... It is still with us, with some niche market potential such as
to power laptops - but constantly spewing out misleading press releases
as if it were still vibrant. But they cannot deny the reality that as
much as $250 million in stockholder equity has been lost. After millions
was pumped into (mostly Canadian) fuel cells companies between 2000 and
2006 most investors now have little to show for it. Ballard, the world's
best-known developer of fuel-cell technology has sold off its automotive
FC business at a loss. Hydrogenics Corp. - perhaps the second best known
company, is "streamlining" and one step away from bankruptcy, which is
where other lower tier but (once) high-flyers have ended up. Yet there
is still lots of hype, press releases, and poorly attended conventions
but with a few glimmers of hope.
This may not be the same fate as the solar panel industry, since unlike
fuel cells, at least they do have a distribution network and real
products which can be purchased and used today (at ridiculously high cost).
Jones
