To most solar installers and manufacturers, the roof on a building is generally an obstacle.

For Solyndra and its small number of installers, it has become the secret sauce.

The way the roof interacts with Solyndra's unusual tubular solar module -- and the legal and technical implications that flow from that interaction -- has created an opportunity in certain circumstances that allow the company to compete with, and even undercut, the price for standard crystalline silicon solar arrays.

That's a novel result, because money-losing Solyndra's modules cost far more than crystalline ones. Back in April, Solyndra said its average selling price was $3.24 per watt, well above the $1.75-per-watt industry norm.  And at that price, Solyndra still loses money. Analysts calculate that its production costs are closer to $6.29 per watt.

"The economics are appealing," said Jaime Hahn at Solis Partner, a solar developer. "They have developed a better mousetrap for flat roofs."

The results may also help explain in part why some large companies like Frito Lay and Anheuser-Busch have installed Solyndra systems, despite the turmoil, skepticism and controversy that surround the company. The operative theory on the street was that these companies did it as a favor to Solyndra's investors, who have sunk over $1 billion into the company. Solis has erected a 704-kilowatt, 3,870 Solyndra-based array on the roof of a manufacturing facility owned by LPS Industries in New Jersey.

Solyndra has not invested in Solis, and Solis also installs several crystalline systems, Hahn added.

The key is that the roof in a Solyndra system plays an integral part in power generation, said Hahn. Roughly 18 percent of the light that strikes Solyndra's tubular modules is reflected light from the reflective, white roof below. Solyndra's tubes are placed in patio furniture-like racks a few inches from each other. By contrast, conventional solar panels get virtually none of their light from the roof, because in most cases the panels cover the roof.

In a recent letter ruling, the Internal Revenue Service stated that the reflective properties make the roof part of the solar array. As a result, building owners can obtain a 30-percent federal investment tax credit on the cost of a new white roof.  State credits can also apply.

The roof can also be depreciated over five years versus 29 years, said Solis.

Certified public accountants may now chest bump.

White roofs, meanwhile, can reduce the cooling load inside buildings by 20 percent. Both Secretary of Energy Steve Chu and Art Rosenfeld, the godfather of energy efficiency, are staunch advocates of white roofs. Sanyo has panels that can have the same effect. While the letter ruling only applies to Solyndra, there's no reason others couldn't apply.

Other benefits can follow as well, depending on the condition and nature of the building. Conventional solar panels weigh more than Solyndra modules. Thus, a Solyndra installation can possibly mean avoiding some reinforcement costs, Hahn said.

Conventional panels also have to be tilted for maximum efficiency. "Crystalline wants to be equal to the latitude to get the best bang for the buck," Hahn said.

In New Jersey, that means installing panels at a 35-degree angle. High winds make that impractical. Therefore, the panels are installed at a less efficient 5 to 10 degree angle with ballasts. Southern orientation is also easier to obtain on some roofs with Solyndra modules, Hahn said.

Installation of Solyndra arrays takes around 40 percent less time, which reduces labor costs substantially, he added. Another potential bonus: snow doesn't accumulate on tubular modules unlike flat ones.

The circumstances, however, only fit in particular situations. Others have also noted that the reflective properties are likely overstated. The vast majority of solar installers, analysts and manufacturers can point out other flaws too. Oh, and let's add: yanked IPO, deposed CEO, auditor warning and large factory with not a lot of things coming out the door. No one claims it's morning in Fremont.

Besides that, not everyone needs a new roof.

"They (Solyndra) need to get to a point where you don't have to have a roof bundle to be competitive with silicon. They understand that," Hahn said.

Nonetheless, a perfect storm exists in some situations that give Solyndra a nod. Please insert your comments below.

By the third or fourth quarter of 2011, Solyndra modules are expected to sell for around $1.25 to $1.35 a watt, Han said. Efficiency will inch up from the current 13.5 percent. When factoring labor and other issues, this could make the company more competitive.

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