XsunX performs thin-film solar U-turn

Thin-film solar cell specialist XsunX is to reposition its business for the second time in six years, this time moving out of the market for semi-transparent solar cells used in windows and back into the building-integrated photovoltaic (BIPV) module market where it started.

Although the Aliso Viejo, California-based company started life as a BIPV manufacturer, it switched focus to concentrate on building amorphous silicon thin-film solar modules in late 2003. Following its latest U-turn, it now intends to produce solar cells based on copper indium gallium diselenide (CIGS) which, due to their light weight, are widely touted as a viable basis for building integrated solar panels.

To this end, the firm is scrapping plans to build a $40m (£24m) manufacturing site in Oregon, on which it has already spent about $8.5m of a $21m secured equity line. It started experiencing difficulties in obtaining additional funding towards the end of 2008 and began exploring alternative cross-industry manufacturing approaches to take it in a new direction.

XsunX now intends to develop a small, pilot CIGS facility at an undisclosed location within the next five years for about a quarter of the original price. The company believes it has developed a manufacturing technique that may allow it to reduce costs by using some of the hard disk drive industry's excess manufacturing capacity to produce new high-efficiency, low-cost solar cells.

The two sectors use similar so-called "sputter" deposition techniques to layer thin films on to substrates. Although current production methods are not geared towards providing the precise control required for dealing with small, stationary areas, scientists at the National Renewable Energy Laboratory in Golden, Colorado, have been working on new approaches.

As a result, the aim is to take the lab's work and apply it to existing hard disk drive equipment. XsunX said it has already spent the past few months validating the concept and began developing the baseline process with an undisclosed partner in July.

The ultimate goal is to commercialise the technology by licensing it to third parties and working with joint venture partners. The company believes it could be used in a number of additional markets such as the disk drive industry and the consumer handheld electronics space.

In related news, Germany-based Solarfun Power Deutschland has introduced a new SF2 manufacturing process to create square mono-crystalline solar cells and modules. The company said the square design increases the amount of surface area able to absorb light, resulting in an efficiency boost of up to five per cent on the company's existing cells.