Desert solar Plants In this page I decided to address the large Desert Solar Electric Generation Plants. In California.  The US now intends to fill the Deserts with Solar Electric Generation Plants. These plants have relatively large capacity ratings and will be placed at various locations in the California desert. I suspect that some  will not get funded. Albert Gore says we have enough solar, wind, and geothermal  energy systems to supply the nations need of energy. So the solar plants offered below are a start. But a start to what? I submit,  it will be a start of the proof that solar plants will not do the job. And it will take another ten years to prove it.  The low capacity factor of these plants and the failure of many will prove it. So let's get started. Below is the table of the current status of the proposed  solar  projects in California deserts. The lead agency to review and approve each of these projects is the  California Energy Commission (CEC). It is my understanding that the CEC is not responsible for the technical viability of these projects. The CEC is  responsible only for the environmental  impact of each project. If they fail it is not the CEC's fault. And I think many will fail. As is true of the the recently failed Solar  Power Tower at Daggett . California.  We will have a lot of junk left in the Desert after this effort is over.  The total  combined capacity of these solar plants is  2,527 MWe.

Project Name and Applicant	Location	Size & Technology	Status	My Opinion
Victorville 2 Hybrid Power Project City of Victorville	Victorville	563 MW 513 NG 50 MW solar Trough	Under Review AFC filed 2/28/07	Will Work
Tvanpah Solar Partners Brightsource	San Bernardino County	400 MW Tower power	Under Review AFC filed 8/31/07	Will Fail*
Carrizo Energy Solar Farm Carrizo Energy LLC	San  Luis Obispo county	177 MW Compact Linear  Fresnel Reflectors	Under Review AFC filed 10/25/07	Will Fail**
Beacon solar Energy Project Beacon Solar LLC	Kern County	250 MW Solar Trough	AFC Filed 3/14/08	Will work
Hybrid Gas-Solar City of Palmdale	Palmdale	570 MW 520 Natural Gas 50 MW solar Trough	AFC Not Yet Filed	Will Work
Harper Lake Solar Harper lake LLC	San Bernardino County	250 MW Solar Trough	AFC not Yet Filed	Will Work
Stirling Solar Thermal One Stirling Energy Systems	San Bernardino County	850 MW 34,000  Stirling Engines	AFC Not Yet Filed	Very Doubtful***
Stirling Solar Thermal Two Stirling Energy Systems	Imperial Valley	900 MW 36,000 Stirling Engines	AFC Not Yet Filed	Very Doubtful***
OptiSolar Photovoltaic Cells	San Luis Obispo County PG&E	550 MWe	Not Yet Filed	Will Work
Sun Power Photovoltaic Cells	San Luis Obispo County PG&E	250 MWe	Not yet Filed	Will Work

 * I think that the systems marked with an asterisk will have problems because they do not use an intermediate fluid to receive  the sun's energy to heat the feedwater entering the steam generator. This provides  a very stable well known energy balance. Steam Turbines are made to accept  well known steam inlet conditions.  I do not think the systems with direct hearing from the sun's energy to water- steam can be well known or controlled.

** These system marked with two asterisks suffer the same problem as above.  The  10 MWe Tower Power system at Daggett,  California  started with  the sun's ray's directed to the water in the tower  to produce steam., and it failed.  Later they used a heat transfer  medium, but it also failed because the heat transfer medium froze in the steam generators. They could have prevent  this problem, but failed to do so.

***  These are the Stirling systems, some 1,750 MWe produced by 70,000 individual 25 kWe capacity machines.  Can they actually maintain this many machines? They need to learn how to manufacture and keep these units in top shape. These  units have no reserve energy capacity. If or when the sun goes under cloud cover they would  all drop out, requiring the utility to have an enormous amount of spinning  reserve power plants on standby.

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The California Environmental Quality Act requires special emphasis should be placed on environmental resources. I wonder how this racks up with the need for copious amounts of water to keep the panels clear?  (c) Knowledge of the regional setting is critical to the assessment of environmental impacts. Special emphasis should be placed on environmental resources that are rare or unique to that region and would be affected by the project. The EIR must demonstrate that the significant environmental impacts of the proposed project were adequately investigated and discussed and it must permit the significant effects of the project to be considered in the full environmental context

Apparently Solel has bought the parabolic Mirror system at Kramer's junction and intends to build  a giant new solar plant in the Mojave Desert.

Solel Inc. is developing the 553 MW Mojave Solar Park 1 (MSP-1), the world's largest solar thermal power plant, in California's Mojave Desert.  In July 2007, Solel Inc. concluded a 25 year Power Purchase Agreement with Pacific Gas and Electric (PG&E) to provide it with electricity from MSP-1.  Solel will build MSP-1 using Solel 6, Solel's industry leading solar thermal collector.   MSP-1 will encompass nine square miles and will provide PG&E with 1,388 gigawatts of energy annually at a price competitive with plants powered by fossil fuels.

Of all of the desert solar system, I think this one has the best chance of succeeding. The reason for this is due to the fact that the solar  panels heat a heat transfer fluid in tubes running through the parabolic reflectors. The fluid is then stored in a large tank and is pumped to a shell and tube stream generator that heats water to steam for the turbine. This intermediate heat transfer fluid allows the system to carry out a more controlled heat balance of the power plant system.

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In a  feasibility study performed by the Electric Power Research Institute  (EPRI) found that the most feasible solar technology system currently available for a large scale plant is the parabolic trough.

My comment: I agree  with the above statement. I think the reason for this is due to the use of an intermediate heat transfer  fluid.  The parabolic trough heats this fluid which  then goes into a holding tank. The thermal properties of the fluid in the holding tank are well known. This fluid is then pumped into the shell side of the steam generator to heat the feedwater coming for the Rankine cycle  of the power plant. This makes it possible to  have well known hot  fluid thermal conditions at the inlet to the steam generator. This provides good control heat balance  over the process of generating the steam conditions going to the turbine.  Generating steam is not a simple process. It requires well known conditions of the heating process and feed water inlet parameters.

The above reasons are why  I think the Tower Power and Fresnel Panel systems will not be as successful as the parabolic trough systems.

Moreover, the Parabolic Trough system is the only  a proven system in California over the last thirty years. The Tower Power system at Daggett California was a dismal failure and it was abandoned.

At  Kramer Junction, California, there is  a solar installation called SEGS (Solar Electric Generating System, built by LUZ International), of which there are nine units. SEGS uses an array of parabolic mirrors (see picture), laid out on north-south axes to concentrate reflected sunlight onto a black tube through which therminol flows. The solar-trough array at Kramer Junction, California.

The shiny surfaces focus sunlight onto the black tubes that run along the array. The therminol fluid, thus heated, is pumped to a heat exchanger where it is used to boil water for a (Rankine) steam cycle system. As the sun moves from east to west, the reflectors rotate so as to keep facing the sun. 

To operate at peak efficiency the mirrors are pressure washed every ten to twenty days. If you want a full explanation and analysis of the SEGS system go to the NREL.com site. But be careful they are, in my opinion too optimist about the future of this concept. Also they are not too free on relating the capacity factors of the system. Low capacity factors are the bane of renewable  energy systems. The capacity factor of the SEGS plant when operating on solar energy alone is only 25 percent.

It appears that the parabolic trough  system has been adopted as the favorite for concentrating solar plants. Below is a recent announcement for such a plant being built in Nevada

Assembly of the parabolic-trough system components is underway for a 64-Megawatt Nevada plant, which will generate enough electricity to power about 11,000 homes.

Here is what what the Department of Energy Thinks about the trough system.

 Trough systems are commercially available and in use today. However, because of the very low cost of today's fossil fuels, they cannot yet compete on a cost-of-electricity basis with fossil-based systems,. A favorable financing arrangement—one likely to be stimulated by green power markets—could enable parabolic troughs to begin to play a role in the marketplace, however. And as global demand for clean energy sources rises, trough systems will become more financially attractive.

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The Linear Fresnel Reflector solar System

The Carrizo Energy Company intends to construct a 177 MWe Linear Fresnel Reflector System in  San Luis Obispo County, California.  PG&E has contracted to take the energy from this system. 

It should be noted that PG&E is not putting any money in this venture. They are only taking the electric energy if any is ever produced. This is necessary due to the CPUC forcing  PG&E  to go green.

The Project design will incorporate Ausra's proprietary CLFR technology to concentrate solar energy on tubes in an elevated receiver. The concentrated solar energy boils water within a row of specially coated stainless steel tubes in an insulated cavity to produce saturated steam. The steam produced in the receivers is collected in a series of pipes, routed to steam drums, and then to the two turbine generators. Steam used by the steam turbines is condensed back to water and returned to the solar field. The advantage of this design is that lenses are cheaper than mirrors. Furthermore, if a material is chosen that has some flexibility, then a less rigid frame is required to withstand wind load

Prototypes of Fresnel lenses concentrators have been produced for the collection of thermal energy by International Automated Systems. No full-scale thermal systems using Fresnel lenses are known to be in operation.

i am surprised that some organizations will back and finance this system considering that there is no real prototype in existence.  It seem to me that the panels on the desert floor  are so close together that power washing them will be very difficult. Also stainless steel tubes are selected as the tube material to receive the sun's energy and  heat the steam-water in the over  head  Fresnel tubes arranged horizontally.  In the US we do not use stainless steel to receive heat  and transport  steam- water because stainless steel cannot withstand impurities such as caustics in the water-steam  systems.

I think they should have arranged the tubes in a vertical direction  with  the down comer tubes in the center and  the heated tubes around the out side.  This would provide a natural circulation steam steam-water system  and it does not require multiple steam drums in series..

I cannot envision what kind of heat transfer-heat balance they will get with the steam water mixture flowing horizontally  in the tubes.

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PG&E makes huge solar deal

UTILITY PROJECT WOULD PUT FIVE POWER PLANTS IN MOJAVE DESERT

By Matt Nauman
Mercury News

Article Launched: 04/01/2008 01:34:35 AM PDT

Green Energy

Pacific Gas & Electric today will announce the largest series of solar-power contracts in the utility's history. The deal, to buy as much as 900 megawatts of electricity - or enough to power 540,000 California homes each year - involves five plants to be built during the next decade.

If the solar-thermal power plants designed by Oakland's BrightSource Energy become operational, a significant amount of power for PG&E customers could come from the sun that beats down on the Mojave Desert.

"From what I know, this is the biggest commitment ever in the history of solar," said John Woolard, BrightSource Energy's chief executive officer and president. "It's a fairly significant undertaking on both sides."

Building all five plants in the Mojave will cost $2 billion to $3 billion, Woolard said. The project, which faces regulatory and financing hurdles, could mean 2,000 construction jobs, and employ about 1,000 workers to operate the plants. PG&E didn't disclose the financial details of the contracts

My comments: Matt Nauman is a fine fellow, but as is true of most newspaper reporters, he knows nothing about energy. In the first place PG&E did not buy 900 megawatt of electricity because this is only the power rating of the 900 MWe facility,  it is not electrical energy. PG&E bought nothing, and has taken no financial liability.  PG&E will pay for the energy kWh produced by the BrightSource company's solar power plant, if there ever is any. And the rate PG&W will pay has not been determined.

PG&E must commit to buying energy from solar plants as required by the State of California. If the rate is too high the State must reimburse PG&E for part of the cost of energy. This means you the tax payer will chip in.

As for a 900 MWe power plant. it probably will never get built because it requires many financial backers for such a project. Are there that many suckers out there? I think not.

Moreover, 900 MWe plant capacity will only provide enough electric energy for 160,000 homes, not 540,000. And they will have to power wash the panels every 10 days or so.

It appears that these  these plants will be the Tower power configuration. Perhaps the Brightsource Energy  Co. should visit the Tower Power Plant  at Daggett, CA. They did not work at all.

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Review Process Begins for Solar Thermal Project in Kern County

Sacramento - 5/22/08 The California Energy Commission today accepted an application to build a 250-megawatt solar thermal generating complex in Kern County. By a vote of 5-0, the Commission said it has enough information to begin the review of the Beacon Solar Energy Project proposed by a wholly owned subsidiary of Florida Power and Light Company. After finding the application for certification (AFC) from Delaware-based Beacon Solar LLC "data adequate," the Commission assigned a committee of two to lead the 12-month review of the proposed plant. Commission staff will now begin the data discovery and analysis phase of the licensing process. Commissioner Karen Douglas will head the committee that will ensure that the project meets the requirements of the California Environmental Quality Act. Commissioner Jeff Byron will serve as the Associate Member.

Beacon Solar LLC plans to develop the project on the western edge of the Mojave Desert along the California State Route 14 corridor, about four miles from California City and 15 miles from the town of Mojave. The Beacon Solar Energy Project would be situated on 2,012-acres of private land that used to be an agricultural site. The project would produce electricity using parabolic trough solar thermal technology. Thousands of parabolic mirrors assembled in rows would receive and concentrate the solar energy to produce steam for powering a steam turbine generator. If approved by the Commission the project will begin construction in the third quarter of 2009, with commercial operations targeted for the third quarter of 2011.

My Comments: They did not say what utility would get the energy from this plant. The parabolic trough is what I think will be the most successful. Perhaps we will see some day how much energy this plant will produce.

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Stirling Engines Mirror- Solar Systems 

Pictures are two views of  fields of Stirling Engines mounted on a mirror which focuses the sun's photons onto the the engines mounted on the mirror assembly. The mirrors will track the suns movement throughout the day.

On August 11, 2005, Southern California Edison announced an agreement to purchase solar powered Stirling engines from Stirling Energy Systems[5] (SES) over a twenty year period and in quantity (20,000 units) sufficient to generate 500 megawatts of electricity. These systems - to be installed on a 4,500 acre solar farm - will use mirrors to direct and concentrate sunlight onto the engines which will in turn drive generators. Each Stirling engine-mirror module assembly has a power capacity of 25 kWe (33.4 hp)

Stirling Energy Systems (SES) is a systems integration and project management company that is developing equipment for utility-scale renewable energy power plants and distributed electric generating systems ("gensets"). SES is teamed with Kockums Submarine Systems, NASA-Glenn Laboratories, the U.S. Department of Energy (DOE), and The Boeing Company for solar power plants. SES is positioned to become a premier worldwide renewable energy technology company to meet the global demand for renewable electric generating technologies through the commercialization of its own Stirling cycle engine technology for solar and genset applications.