Sandia Lab News, October 29, 2004

Vol. 56, No. 22 October 29, 2004

Albuquerque, New Mexico 87185-0165 || Livermore, California 94550-0969
Tonopah, Nevada; Nevada Test Site; Amarillo, Texas

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Sandia joins forces with Stirling Energy Systems to build, test mini power plant of six solar dish systems		Presidential Science Advisor John Marburger receives Sandia science overview

Sandia joins forces with Stirling Energy Systems to build, test mini power plant of six solar dish systems

By Chris Burroughs

Sandia is joining forces with Stirling Energy Systems, Inc. (SES) of Phoenix to test six new solar dish-engine systems for electricity generation that will provide enough grid-ready electricity to power more than 40 homes.

Five new systems will be installed between now and January at Sandia’s National Solar Thermal Test Facility. They will join a prototype dish-Stirling system erected earlier this year, making a six-dish mini power plant producing 150kW of grid-ready electrical power.

“This will be the largest array of solar dish-Stirling systems in the world,” says Chuck Andraka (6218), the Sandia project leader. “Ultimately SES envisions 20,000 systems to be placed in one or more solar dish farms and providing electricity to southwest US utility companies.”

Sandia and SES staff will work together over the next couple of months to assemble the five new state-of-the-art systems.

Each unit, which consists of 82 mirrors formed in the shape of a dish, will be nearly identical to the system installed earlier this year with some modifications to improve the design. The frame is steel made by Schuff Steel, also of Phoenix, while the mirrors, provided by Paneltec of Lafayette, Colo., are laminated onto a honeycomb aluminum structure invented and patented in the late 1990s by Sandia researcher Rich Diver (6218). The engine will be assembled at Sandia’s test facility using parts that were contracted out by SES.

Once the units are installed, Sandia and SES researchers will experiment with the systems to determine how best they can be integrated in a field, as well as improving reliability and performance.

“It’s one thing to have one system that we can operate but a whole other thing to have six that must work in unison,” Chuck says.

Each unit operates automatically. Without operator intervention or even on-site presence, it starts up each morning at dawn, operates throughout the day, responding to clouds and wind as needed. Finally it shuts itself down at sunset. The system can be monitored and controlled over the Internet. Researchers want to make the six systems work together with the same level of automation. The controls and software that perform this integration will be scalable to much larger facilities.

The solar dish generates electricity by focusing the sun’s rays onto a receiver, which transmits the heat energy to an engine. The engine is a sealed system filled with hydrogen, and as the gas heats and cools, its pressure rises and falls. The change in pressure drives the pistons inside the engine, producing mechanical power. The mechanical power in turn drives a generator and makes electricity.

The cost for each prototype unit is about $150,000. Once in production SES estimates that the cost could be reduced to less than $50,000 each, which would make the cost of electricity competitive with conventional fuel technologies.

Bob Liden, SES executive vice president and general manager, says solar electric generation dish arrays are an option for power in parts of the country that are sunny like New Mexico, Arizona, California, and Nevada. They could be linked together to provide utility-scale power. A solar dish farm covering 11 square miles could produce as much electricity per year as Hoover Dam, and a farm 100 miles by 100 miles in the southwestern US could provide as much energy as is needed to power the entire country.

“Another application could be to operate as stand-alone units in remote areas off the grid, such as the Navajo reservation, and supply power to one or several homes,” Liden says. Stand-alone units have already been demonstrated as an effective means of pumping water in rural areas.
He notes the dish-Stirling system works at higher efficiencies than any other current solar technologies, with a net solar-to-electric conversion efficiency reaching 30 percent. Each unit can produce up to 25 kilowatts of power.

“This is the perfect type of electricity generation for the Southwest,” Liden says. “It’s a renewable resource, pollution free, and the maintenance of a solar farm is minimal.”

One of the system’s advantages is that it is “somewhat modular,” and size of the facility can be ramped up over a period of time, Chuck says. That is compared to a traditional power plant or other large-scale solar technologies that have to be completely built before they are operational.

The cooperation between SES and Sandia is seen as critical to the success of this technology. This on-site teaming is a new way of doing business in the energy field and is being watched with interest at DOE headquarters. Chuck says, “There is no more effective way of providing technology transfer.”

Of the aggressive schedule SES is pursuing in moving from this prototype power plant to large-scale production, Chuck says, “It’s a big step to go from one to six dishes and ramp them up the way they want. But we have such a good relationship with SES, and we work together so well that we should be able to meet this challenge.” -- Chris Burroughs

Presidential Science Advisor John Marburger receives Sandia science overview

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By Michael Padilla

Responding to a wide spectrum of national issues is a major strength of Sandia, said John Marburger, science advisor to President Bush and director of Office of Science and Technology Policy, during a recent visit to Sandia.

“Sandia is a broad-spectrum lab,” Marburger said after receiving a comprehensive tour and overview of Sandia. “Sandia’s responsiveness to the nation is outstanding.”

He said he was impressed with the quality and enthusiasm of the employees at Sandia and commended the mission and goals of the Laboratories.

Marburger said Sandia’s work is a perfect fit for the three areas set forth by the current administration. The areas include winning the war on terrorism, protecting the homeland, and contributing to economic stability. He said he realizes that science plays a major role in contributing to these areas.

Marburger toured the Microelectronics Development Laboratory, Integrated Materials Research Lab, and the Z machine. Hosted by VP for Science & Technology and Partnerships 1000 Pace VanDevender, Marburger was briefed on the progress of the Microsystems and Engineering Sciences Applications (MESA) project, the Biotechnology Program, and Global Nuclear Futures.

Marburger said making things smaller and faster is key in meeting the challenges of the new century

“The smaller the scale, the more robust technology can be,” he said. “The use of information and image technology all lead to useful products.”
He said Sandia’s MESA project will play an important role in the area of nanotechnology.

Nanoscale structures, he said, will lead to opportunities for new devices as small as molecules, and machines as small as human cells.

Work in the area of biotechnology helps pave the way toward better diagnostics, therapies, treatments, and possible cures that affect the lives of all Americans, he said.

Moving new technology from the lab to products is a difficult task, he said, adding that certain technologies can transfer more rapidly than others.

“The key to successful technology transfer is to encourage flexibility within the process,” he said. “We need to make sure the transformation is safe and feasible, but we need to do this quickly.”

Prior to his appointment to the Executive Office of the President, he served as director of Brookhaven National Laboratory from 1998, and as the third president of the State University of New York at Stony Brook from 1980-1994.

“Sandia is well-run and has a strong vision and a good vision,” he said. “I am leaving with a very favorable impression of the Labs.”

-- Michael Padilla