Trend: The most promising mechanism for large scale solar power generation is solar thermal power.
The Oil Drum provides an optimistic view of solar thermal power /concentrating solar power as a cost/effective, clean source of energy in the near future.
Link: The Oil Drum | Concentrating On The Important Things - Solar Thermal Power.
Solar thermal power is often referred to as concentrating solar power, or CSP.
Concentrating Solar Power (CSP) systems use lenses or mirrors combined with tracking systems to focus sunlight which is then used to generate electricity. The primary mechanisms for concentrating sunlight are the parabolic trough, the solar power tower (not to be confused with solar updraft towers) and the parabolic dish. The high temperatures produced by CSP systems can also be used to provide heat and steam for a variety of applications (cogeneration). CSP technologies require direct sunlight (insolation) to function and are of limited use in locations with significant cloud cover.
Solar thermal power plants have been in commercial use in southern California since 1985. An area of desert around 250 km by 250 km covered with CSP power generation could supply all the world's current electricity demand.
Solar thermal plants can be built in their entirety within a few years - much faster than many conventional power projects. Solar thermal plants are built almost entirely with modular, commodity materials (and thus have short development and construction times) and do not encounter the sort of opposition on environmental grounds that traditional forms of power generation like coal and nuclear face.
Operational plants include :
* US (California) - 354 MW FPL's Solar Energy Generating Systems (SEGS) plant, using parabolic troughs
* US (Arizona) - 1 MW Acciona Energy's Saguaro Solar Generating Station using parabolic troughs
* Spain (Seville) - 11 MW Abengoa's PS10 solar tower
* Australia (NSW) - 35 MW Liddell Power Station using fresnel reflectors
* US (Nevada) - 64 MW Acciona Energy's Nevada Solar One plant (not to be confused with the Solar One / Solar Two experimental plants) using parabolic troughs
Plants currently under construction :
* Spain (Seville) - 20 MW Abengoa's PS20 solar tower
* Spain (Seville) - 20 MW (each) Abengoa's PS20 and AZ20 solar towers
* Spain (Seville) - 50 MW (each) Abengoa's Solnova 1 and 3 using parabolic troughs (5 plants planned in all)
* Spain (Andalusia) - 17 MW Sener's Solar Tres solar tower (molten salt energy storage)
* Spain (Andalusia) - 50 MW (each) Sener's Andasol I, II and III plants (molten salt energy storage)There has been a spate of new announcements regarding solar thermal power over the past year - there are over 5,800 MW of solar thermal plants in the planning stages worldwide.
The company receiving the most attention seems to be Ausra, a company set up by Dr David Mills (who pioneered the CSP plant at the Liddell power plant in New South Wales using compact linear Fresnel-reflector technology) with backing from Vinod Khosla and Kleiner, Perkins, Caulfield & Byers (see here for a brief demo of how their technology works). Mills estimates that solar thermal plants could provide more than 90 percent of current U.S. power demand at prices competitive with coal and natural gas.
Ausra is initially planning a 177 MW plant in California, and has committed to supply 1,500 MW of power to Californian utilities PG&E and FPL. They are also rumoured to be moving in to Texas as well.
PG&E have also signed a 25-year deal with Ausra competitor Solel Solar Systems of Israel to buy power from a 553 MW solar thermal plant that Solel is developing in California's Mojave Desert. FPL has also hired Solel to upgrade the SEGS solar-thermal plants it operates in the Mojave.
Another PG&E contract is with BrightSource to supply between 500 MW and 900 MW of power per year from solar tower plants in California, beginning in 2011, with the first of a number of 100 MW facilities being built in Ivanpah.
Other companies active in the US include eSolar (linked to Google's energy initiatives), RocketDyne and SkyFuel.
Abu Dhabi's Masdar Initiative and Spain's Sener are have formed a joint venture to build and operate concentrating solar power plants across the world's sunbelt regions called Torresol Energy.
Algeria and Germany have signed a a joint research agreement for the development of a new generation of large-scale, low-cost solar thermal power plants (which could contribute to the Desert-TREC vision of large scale CSP in North Africa powering Europe, which I once dubbed "Deserts Of Gold").
More new plants are being planned in :
* Algeria - 20 MW Abengoa's plant in Hassi-R'Mel
* Australia - 10 MW Queensland State Government facility in Cloncurry
* Australia - 154 MW Solar Systems and TRUEnergy's plant in Mildura
* Egypt - 70 MW plant in Kuraymat
* Iran - 17 MW plant in Yazd
* Israel - 250 MW plant in Ashalim
* Morocco - 20 MW Abengoa's plant in Ain-Ben-Mathar
* US (Arizona) - 280 MW Abengoa and Arizona Public Service's plant in Gila Bend
* US (California) - 50 MW Inland Energy's plant in Victorville
* US (California) - 250 MW FPL Energy's Beacon Solar Energy ProjectFeasibility studies are also being done in Oman, China and Mexico.
Most of the plants in the middle east are combined gas / solar thermal plants, with the numbers above representing the solar component only.
Energy Storage
One of the key differentiating factors between solar thermal power and solar PV is that heat energy is more easily (and efficiently) stored than electricity, with solar thermal plants often combining energy storage into the design to enable around-the-clock, dispatchable electricity generation.
Most solar thermal plants are looking to use molten salt for storing energy - other alternatives being developed are graphite (in the Cloncurry development), heated water / steam (for the Ausra plants) and heat-transfer oil such as therminol (for the Abengoa plant in Arizona).
Cost
The existing plants prove that concentrated solar power is practical, but costs must decrease. Electricity from solar thermal plants currently costs between US$0.13 per kilowatt hour (kWh) and US$0.17 per kWh, depending on the location of the plant and the amount of sunshine it receives. Conventional power plants generate electricity for between US$0.05 and US$0.15 per kilowatt hour (not including any carbon taxes or cap and trade related costs) but in most places it's below US$0.10 (wind power generally costs around US$0.08 per kWh).
Heat is hot! But the best news of the century is free fuel, dude! solar trough collectors are the new tech, it seems, but dish sun catchers, of 100 kw ea., and 5 to the acre or 3200 per sq. mile equals 320 mega watts per section of land, at a peak power price of .105 cents per kwh, we are talking about $126 thousand bucks revenue per acre per year, or $80 million per sq mile per year. Not to shabby for catching sun shine. These sun catchers are high {our sun catchers} tech in the electro-mechanical operators and cpu controllers,- and the boilers & related plumbing, 90 percent of our units consist of of the shelf mechanical and inovative materials applications.You ain't seen it, bro, till you have seen a 20 meter dia. dish catching over a million btu's of heat energy and solar flux boiler that can vaporize 350 lbs. of fluid per hour @ 135 hp. Now that is not renewable enery--, no bro, that is new energy production!USING FREE FUEL!!. You wan't on this team ? email me.
reis.bob7@gmail.com.,
Posted by: reis,bob7 | August 09, 2008 at 06:51 PM
PS.,Bro.,forgot to mention in my earlier post that the boiler that receives 500 kw[1.7 million Btu']of heat energy {converts it into electric power @ 32% efficiency} uses linear alternators to generate power at the CENTRAL DISH!
Posted by: reis.bob | August 09, 2008 at 07:04 PM