The Agua Caliente concentrating solar power plant is already under construction on private land near Dateland, while Arizona Public Service Co. recently announced plans for a solar thermal plant near Hyder.

Yuma County’s sunny weather is attracting more than winter visitors — it’s also a lure for solar energy projects with a potential for at least five concentrating solar power plants being developed in the next few years.

The Agua Caliente concentrating solar power plant is already under construction on private land near Dateland, while Arizona Public Service Co. recently announced plans for a solar thermal plant near Hyder to be built next year.

Three additional solar concentrating solar power projects have been proposed to be located on federal land in Yuma County, with a fourth pending in nearby Hyder Valley just across the county line, according to the U.S. Bureau of Land Management. Together, they would generate thousands of megawatts of power.

The use of solar energy can be found today all over Arizona on private land. Small commercial facilities and self-supporting structures such as streetlights and weather stations are everywhere.

In 2008, BLM Arizona experienced a “gold rush” of right-of-way applications for concentrated solar energy facilities across the state. Solar development companies or “prospectors” are looking at portions of the 12.2 million acres of public land administered by the BLM in Arizona as potential areas for concentrated solar energy generators.

Friday, Secretary of the Interior Ken Salazar and Secretary of Energy Steven Chu announced a comprehensive environmental analysis that has identified proposed “solar energy zones” on public lands in Arizona, California, Colorado, Nevada, New Mexico and Utah most suitable for environmentally sound, utility-scale solar energy production.

The detailed study, known as the Draft Solar Programmatic Environmental Impact Statement (PEIS), was compiled over the past two years as part of the Obama administration’s efforts to create a framework for developing renewable energy in the right way and in the right places, stated a news release.

Arizona has three proposed solar energy zones, with a total of 16, 492 acres. They include the large-scale Sonoran project south of Buckeye, the Quartzsite project in La Paz County north of Interstate 10 and the Hyder Valley project east of Hyder.

Criteria for selection as a solar energy zone included relatively flat land, access to power transmission lines, no significant cultural sites and no established endangered species, said David Godfrey, public affairs specialist for the BLM office in Arizona.

While Yuma County was not selected as a solar energy zone, it still is busy as a site for proposed solar projects on both private and public lands, Godfrey noted.

Pending solar projects for which applications have been made for rights of way on federal land in Yuma County include:

• Palomas, a 500-megawatt solar plant to be located in the Hyder area. The applicant is First Solar.

• Agua Caliente, a solar project that is independent of the Agua Caliente that now is under construction in eastern Yuma County. This project is proposed by Solar Reserve on federal land to be located on the Yuma-Maricopa County line north of Interstate 8. It would generate 600 megawatts of power.

• Wildcat Quartzsite to be located south of Quartzsite along U.S. 95 would generate 800 megawatts of power. The applicant is Bright Source Energy.

These projects are all in the very early stages and still have to work through the environmental review process, Godfrey said. “They’ve filed the paperwork but not a lot is going on.”

The Hyder Valley solar project would generate 325 megawatts of power. It is further along than the other projects pending for federal land in southwestern Arizona, Godfrey said. Construction could start in 2013.

In contrast, the Agua Caliente plant now being developed by First Solar would generate 290 megawatts of power slated for Southern California. It is scheduled for completion in 2013.

The APS plant in Hyder would provide 17 megawatts of power, enough for 4,250 homes, that is slated for APS customers in Arizona. Construction is expected to begin in June and be completed by late 2011. The plant is being developed by SunEdison for APS.

Godfrey said CSP (concentrating solar power) technology is being proposed for the solar plants on the federal land, versus photovoltaic technology in the Agua Caliente and APS Hyder plants.

CSP technology concentrates solar power, converting it to high-temperature heat that is channeled through conventional generators, according to a website on the technology. It tends to use more water for cooling than photovoltaic systems. But it has some advantages, such as a potential for storing the solar power.

California approves more Big Solar projects

The California Energy Commission on Wednesday approved two more big solar thermal power plants, ending the year having green-lighted a total of nine projects that would generate 4,142.5 megawatts if all were built.

That’s enough carbon-free electricity to power more than three million homes. The question now is, how many of those massive solar farms will actually break ground?

Hours after the energy commission vote, a federal judge temporarily blocked construction of Tessera Solar’s 709-megawatt Imperial Valley power plant in the Southern California desert in response to a suit by the Quechan Native American tribe.

The Quechan sued the United States Interior Department in October over its approval of the project, arguing that the government failed to adequately consult with the tribe over the impact of installing 28,360, 40-foot-tall solar dishes on its ancestral lands.

The Quechan argued the project would harm the flat-tailed horned lizard, an animal proposed for endangered species protection that is part of the tribe’s creation story.

"Tessera Solar is deeply disappointed with the federal court’s ruling last night," Robert Lukefahr, Tessera’s chief executive, said in a statement on Thursday. "This ruling sets back our ability to provide clean, renewable power to Southern California and delays our ability to bring jobs and economic development to a region with the highest unemployment rate in America."

Lukefahr pointed out that El Centro, a city 14 miles from the Imperial Valley project, suffers an unemployment rate of 29.3 percent.

However, a Reuters story last night reported that Tessera had put on hold the Imperial Valley power plant as well as its 663.5-megawatt Calico project in the Mojave Desert due to difficulties in raising financing to build the solar farms. But on Thursday, Tessera spokesperson Janette Coates told me that the projects had not been abandoned.

"We are actively seeking equity for our Imperial Valley Solar and Calico Solar projects and the actual start of construction will depend on project financing and compliance work which is ongoing," Coates wrote in an email. There was some good news on Wednesday for the developers seeking to finance such multibillion-dollar renewable energy projects.

The U.S. Senate passed a one-year extension of a crucial cash grant program that was set to expire at year’s end. The program allows developers to receive a cash payment to cover 30 percent of a renewable energy project’s cost in lieu of receiving an investment tax credit. The House of Representatives was set to take up the extension of the cash grant program on Thursday.

The Draft Solar Energy PEIS document is available online at http://solareis.anl.gov. Maps are available at http://blm.gov/td5c.

The public is encouraged to provide comment on the draft plan during the next 90 days. Written comments can be submitted at http://solareis.anl.gov or mailed to: Solar Energy Draft Programmatic EIS, Argonne National Laboratory, 9700 S. Cass Ave. – EVS/240, Argonne, IL 60439.