BILLERICA, Mass., Jan. 9 -- ASE Americas, a manufacturer of high-performance solar electric cells and modules, is expanding its solar wafer production from 12 to 20 megawatts per year. The move follows two other expansions of the firm's manufacturing facility in Alzenau, Germany. The expansions result from demand for ASE's solar cells and 300-watt solar electric modules. Increasing the volume of our world-leading crystalline silicon, EFG technology will further improve ASE's cost advantage , said Tom Zarrella, COO for ASE Americas. With our resource efficient EFG wafer, state-of-the-art continuous cell manufacturing, and large area module, we have made important steps to making solar electricity a widespread source of energy. Work on the expansion has begun and will be completed by the fall of this year. ASE grows thin hollow octagon tubes, 20 feet in length, from molten silicon and uses lasers to cut the tubes into square and rectangle shapes. The silicon substrates are then processed into electricity generating solar cells. This process (called edge-defined film-fed growth or EFG) is the most efficient in the industry. New growth units and lasers will be ready for testing and installation by late summer, the company said.