Whorled View

Probably one of the best layman articles on the subject from a contemporary perspective except for one major problem. Nevertheless it’s worth a good read. Check it out: http://www.sciam.com/article.cfm?id=a-solar-grand-plan

The problem: Once again it places more emphasis on Solar PV than Solar thermal. It pretends to justify this by throwing around some magical numbers that at this point are pure theory and highly unlikely. Compare that to Solar thermal where the numbers are even better and are proven.

Solar Thermal is cheaper and always will be.

Case in point: It says Cadmium Telluride (nanosolar film) will be able to produce electricity for $0.05/kWh by 2020. This is based on the theory that they can get efficiencies up to 14%. I’m sorry, but I’m quite convinced that in order to do that they’ll have to enable some technologies that will up the price of the manufacturing enough to blow that number out of the water. They think they can improve the efficiency by 40%, based on what? Silicon solar efficiencies have improved maybe 10% in the last 20 years? Sure Cadmium Telluride went from 8% to 9% in the last year, but they’re approaching a ceiling that will get extremely hard to raise. My guess is that it will top out at 12%, which leaves solar PV maxing out at $0.06/kWh assuming all other costs stay the same, which they won’t. Add to that $0.04 /kWh for storage and you get 0.10/kWh, AND YOU HAVE TO WAIT UNTIL 2020 TO SEE THAT RESULT.

Compare that to Ausra’s Solar thermal technology which by 2013 should produce electricity, including storage, at $0.07 /kWh.

HELLO!? Am I the only one running these numbers? Solar Thermal is so superior. Nothing, I repeat: NOTHING should go toward the development of something that will cost more near term and long term than Solar Thermal will.

Two more reasons Solar thermal is better:

TIME TO MARKET: Solar Thermal can scale up to supply all our needs at coal prices by 2015 if we wanted to. Unlike any kind of Solar PV solar thermal uses no fancy technology. It uses no special materials that require special processing. The materials and the parts and pieces that make solar thermal plants are found all throughout existing industrial parks across America -and at bargain prices. All you need is the money to buy the supplies (tons cheaper than what Solar PV factories cost), and people to build them (requires no special training or science). All these things are in stark contrast to the supply problems that have plagued the Solar PV industry. Solar PV, whether it’s thin film or otherwise, will never be able to scale up at the rate that the Scientific American author suggests. The materials and processing equipment demands are just too great even if the money was there … can’t be done.

LIFETIME: A solar thermal plant lasts almost forever if cared for correctly, with few replacement parts, and reasonable maintenance. Sure parts of the turbine needs replacing as with any turbine including the ones used by SolarPV to reconvert pressurized gas to electricity, but thats about it. No solar cells to replace. The mirrors last forever. The dewar tubes containing the molten salt or H2O (Ausra’s technology) should last a very long time if maintained right. Compare that to SolarPV where the life of the Solar Cells is 20-30 years at the most. Also you’ll have to replace the compressors as well as the turbines parts in the Solar PV plant (incidentally solar thermal needs no compressors - another bonys). Can you imagine that? With a Solar PV plant you’re replacing practically the whole plant every 20-30 years. Not so with Solar Thermal.

In short, media bias favoring Solar PV once again garners unworthy support, thereby siphoning off the funds from Solar Thermal, possibly in order to fatten the wallets of those who invest in Solar PV (Al Gore) or work for the industry. Solar PV, even in Cadmium Telluride thin films will forever be inferior, less efficient, and a more expensive technology than Solar thermal. Articles like this that have some fantastic information and promote the use of the Sun’s rays almost do more bad than good by obfuscating the issue and guaranteeing that our hard earned tax dollars will be taken away from Solar Thermal and reinvested in Solar PV assuming that Solar PV will someday meet the magic numbers that it was supposed to achieve 20-30 years ago, and neither will we solve our energy problems as quickly as we could if all the funds went to something like what Ausra does (www.ausra.com ).

1. Electricity produced by CSP can be as cheap as 8 cents per kWh. That’s about 20% cheaper than most people are paying in the united states right now for electricity. That’s 1/4 the cost of electricity produced by the ever so much more popular Solar PV panels.
2. A 92 x 92 square mile CSP farm placed in the empty barren desert in the SW United States could produce all the energy needed by the whole United States.
3. It could easily solve the desalinated water shortage crisis - which for many countries is a much bigger problem than any kind of oil shortage crisis.
4. Only 0.3% of the Sahara desert is needed to power most of Europe and upper Africa, resulting in a 70% carbon reduction for the region. It will save astonishing amounts of money too as cities must otherwise relocate costing of 100’s billions of dollars, whereas it could all be averted with a CSP plant in the $10 billions of dollar range.
5. Since 90% of the world lives relatively close to desert or to substantial power grids connected to such areas then 90% of the world’s population can be served by this breathtakingly economical and clear resource.

The Polywell Fusion Reactor

That said, don’t confuse a fusion (fuse atoms together) reactor with a fission (tears atoms apart) reactor. Dangerous and dirty fission is what all contemporary nuclear reactors use. If it helps you, think “fusion = fuse together, or build up”, “fission = tear apart, destroy”. Fusion is usually good because it produces safe byproducts, fission is bad because it usually produces dangerous byproducts and requires radioactive fuel.

Above: a small section of a giant array of parabolic reflective fabric mirrors.

2) Innumerable additional 7 sq.mile mirrors can be simply added, each requiring only one additional structural point, 7 more square miles of reflective fabric, and optics at the focal point of each mirror to send the concentrated solar power to a receiving solar plant on earth.

3) The incoming solar power would be distributed among receiving solar plants strategically placed on earth, so each plant would receive the maximum amount of suns possible without damaging the energy conversion facilities. Maintenance could be performed on these earth-based solar plants at night.

Solar Two facility in California