Solar company Ascent Solar Technologies Inc. will announce today that it has taken a major step toward commercial production of its thin-film modules, which eventually could be used in building materials to produce solar energy.

Ascent says the modules achieved more than 9.5 percent efficiency at its research and development center in Littleton - compared with the 8 percent common among similar products.

High-efficiency modules can generate electricity from solar rays at higher efficiencies than conventional solar panels.

The National Renewable Energy Laboratory also has independently verified that Ascent's modules measured as high as 9.64 percent in efficiency.

"That would be a breakthrough in terms of highest efficiency for a flexible module," said Bolko von Roedern, a scientist at NREL.

Roedern has worked in solar cells and modules based on copper indium gallium selenide thin films, also known as CIGS.

Ascent is developing what's called "flexible CIGC monolithically integrated modules" at the Littleton facility and plans to begin commercial production at a Thornton plant in two years.

"We began the process earlier this year and now this is a step closer to our goal of commercial production by 2010," said Ascent spokesman Brian Blackman.

Ascent bought the 120,000- square-foot Thornton facility for $5.5 million in February to house its world headquarters and commercial manufacturing operations. It plans to spend an additional $4 million to modernize and retrofit it to the company's specifications.

Norsk Hydro ASA, a Norwegian company and Fortune Global 500 supplier of aluminum and aluminum products, owns a roughly 35 percent stake in Ascent.

Hydro has said Ascent Solar's solar modules will provide a "simple, elegant and architecturally attractive means to incorporate photovoltaics into buildings."