That's the sound of the men working on the solar line.

Spire Corp. (NSDQ: SPIR) announced Monday that it will get $55 million to supply solar cells to a solar module factory it has installed at a federal prison.

The Bedford, Mass.-based company also announced last week that it faces the possibility of being delisted from the Nasdaq stock exchange if its market valuation does not rise above $50 million between now and the end of the year.

Whether Spire's $55 million deal with Federal Prison Industries Inc., also known as Unicor, will help it avoid that delisting remains to be seen. The deal calls for Spire to supply solar cells for its turnkey solar module manufacturing line to be staffed by inmates at the Federal Correctional Institution in Otisville, N.Y.

Unicor, a government-owned corporation that runs businesses in federal prisons, plans to staff the Otisville module factory with inmates and sell the modules produced for government installations, Spire reported. The idea is that inmates will get training.

Still, using prison labor has often backfired. Dell experimented once with Unicor using inmates for some minor PC recycling projects, but pulled back after adverse publicity and complaints from workers rights and environmental groups.

Spire will likely receive the same complaints and may even get complaints from homeowners associations. This sort of training, ultimately, could lead to ex-convicts getting jobs that require them to visit people's homes.  

The $55 million contract included only the supply of solar cells, not the cost of the solar module manufacturing line Spire provided to Unicor, said Mark Willingham, vice president of sales and marketing. He did not disclose the price Unicor paid for that line.    

Spire makes crystalline silicon solar module manufacturing lines and has announced deals to provide them to companies including China's ET Solar Group, India's PLG Power Ltd. and Alpex Exports Pvt. Ltd., Russia's Bogoroditsk Plant of Techno-Chemical Products and Martifer Solar in Portugal, according to the company's Website. It also makes solar cell manufacturing lines and has announced deals to sell them to companies including Korea's Hanwha Chemical Corp., according to Spire's Website.

Spire also says it develops and manufactures gallium arsenide (GaAs) solar cells for companies seeking to make concentrating photovoltaic systems, which concentrate sunlight on solar cells in hopes of boosting their efficiency. And the company has announced plans for a thin-film solar panel manufacturing line.

Last month, Spire reported a net loss of $347,000, or 4 cents per share, in the first nine months of 2008 on revenues of $49 million. For the same period in 2007, Spire reported a loss of $856,000, or 10 cents per share, for on revenues of $25.4 million.

On Dec. 1, Spire received a letter from Nasdaq warning that the company could be de-listed from the stock exchange if its market valuation did not rise above $50 million for 10 consecutive days by the end of the year. Spire may appeal that decision to a Nasdaq panel and request a stay of the delisting pending a hearing.

"The Company plans to exercise diligent efforts to maintain the listing of its common stock on The Nasdaq Global Market, but there can be no assurance that it will be successful in doing so," Spire stated in a Dec. 5 press release.