Spectrolab has started production on a new type of solar cell that converts sunlight into electricity at a higher rate than previously possible. The XTJ Prime cells are made at the Sylmar facility of Spectrolab, a subsidiary of Boeing Co. that manufacturers solar cells and panels for use on satellites and other spacecraft. Spectrolab President Tony Mueller said the XTJ Prime follows the legacy of innovation that the company has been pioneering for decades. “We’ve produced more than anyone else on more spacecraft than anyone else,” said Mueller, who took on his position last year. Spectrolab employs 250 workers who develop and manufacture the photovoltaic cells, as well as high-intensity searchlights, in a 180,000-square-foot plant on 6 acres in the east San Fernando Valley. The company has made more than 4 million multi-junction solar cells that have been used on 600 spacecraft. It has also made 3,000 searchlights used by police departments and military around the world. It holds more than 100 active patents. Efficiency gains Spectrolab is part of the defense, space and security unit of Chicago-based Boeing, an aerospace and defense giant that generates more than $30 billion in revenue. Spectrolab sales are not broken out separately. While much of the work Spectrolab does is for Boeing projects, it can make its solar panels for any customer, including competing aerospace companies. Dave Messner, an aerospace engineer with Orbital ATK Inc., in Dulles, Va., said the two companies have worked together three decades since Orbital got into solar arrays. “Our company would not be where it is today without the innovation that comes from there,” Messner said. The solar cells convert sunlight into electricity used to power a satellite or another spacecraft. The best cells have a 29 percent efficiency, so the 30.7 percent efficiency of the XTJ Prime gives more than a 1 percent gain that helps drive the value of the cells in the marketplace, Mueller at Spectrolab said. Technological advances allow the company to make the cells at a lower cost than previous cells, he added, “We’ve been able to make it larger as well,” Mueller said. “What was 70 square centimeters can now maybe go up to 80 square centimeters.” Spectrolab also makes ground-based solar panels that have achieved an even higher efficiency rate. In 2013, the company set a record of 38.8 percent efficiency, beating by more than 1 percent the previous record, also set by Spectrolab, earlier that year. Brad Clevenger, chief executive of SolAero Technologies Corp., an Albuquerque, N.M.-based competitor of Spectrolab, estimated the worldwide market for supplying solar panels to satellites at about $200 million. The combination of cells that weigh less, have higher efficiency and can last longer in the harsh space environment has resulted in more powerful and capable satellites being launched, Clevenger wrote in an email to the Business Journal. “Many satellites launched today could not have been launched 20 years ago because they would have been too massive or physically too large to fit into or be lifted by launch vehicles,” he explained. Mann’s beginnings Announcement of XTJ Prime coincided with the 60th anniversary of Spectrolab. The company was the first to be founded by the late serial entrepreneur Alfred Mann and quickly found its niche with the burgeoning U.S. space program, starting with Pioneer I in 1958, the Explorer 6 satellite the following year and Syncom in 1963, the first geosynchronous satellite. When Apollo 11 landed on the moon it brought along solar cells made by Spectrolab. The company has powered the Mars rovers Spirit and Opportunity and made the 275,000 solar cells powering the International Space Station. And last month the Juno spacecraft with three 30-foot-long Spectrolab solar arrays went into orbit around Jupiter nearly 500 million miles from earth – the longest distance a solar powered vehicle has ever traveled in space. “People said there was no way to use solar power (for Juno),” said Mark Spiwak, president of the Satellite Systems International business at Boeing. “NASA decided to take a chance and include Spectrolab in their plans. Look what we got.” Mann sold Spectrolab to Textron Inc. in 1960 and then it was sold in to Hughes Aircraft Co. in 1975. Boeing acquired the division when it bought Hughes in 2000. Making the solar panels starts with a combination of materials and gases put in pressure vessels that grow a crystal used in making semiconductors for the cells. The semiconductors convert sunlight into electricity, Mueller said. How efficient the cells are with that conversion depends on the cell’s design to capture much sunlight as possible, he added. “What we are talking about are slight changes as technology has progressed in terms of material science, production techniques and other attributes to grow the solar cells better and better to become more efficient,” Mueller said. It takes about an hour to grow the crystal used in making the solar cells. Following that is post-processing that includes putting on cover glass 75 microns thick that protects the cell from the cosmic radiation in space. Workers attach connections that link the cells together into something like an electrical grid, Mueller said, adding that that process takes about a month. An additional four months is needed to lay down all the solar cells onto the panels, correctly position them and affix them. “We are talking thousands of cells at that point being laid down on a panel,” Mueller said. Spectrolab so far has one customer for the XTJ Prime cells and will begin delivery of them later this year. While the XTJ Prime has pushed the limits of photovoltaic efficiency, Spectrolab continues to manufacture older, legacy cells and panels for many different satellite programs. Mueller said he envisions that work continuing indefinitely. Engineers, meanwhile will continue to make improvements in increasing efficiency and reducing the cost to make the cell, he added. “That may entail automation, that may entail streamlining operations,” Mueller said.” It may entail revising requirements with customers to make the most efficient solar cell grid on a panel.”
SPECIAL REPORT: Solar Frontier
