Last year, The Solar Energy Co.,Ltd claimed a world record for efficiency of a “transparent solar cell” with a “certified” 9.8% power conversion efficiency. According to the startup, the efficiency of the small-sized organic solar cell was certified by third-party test lab Newport Corporation.*

Organic solar cells (OSCs) are lightweight, nontoxic and semi-transparent. They have long-held the promise of low-cost manufacturing, but their efficiencies tend to be low — and their long-term reliability has been questionable.

Ubiquitous Energy deposits organic layers directly on glass using standard glass coating equipment. According to the firm, the transparent solar coating selectively absorbs and converts ultraviolet and near-infrared light to electricity while letting visible light through. The firm is focusing its initial work on architectural glass. The Ubiquitous Energy team holds a number of patents in organic solar cells and graded solar cell technology.

Commercializing an integrated solar facade is not just an engineering problem. It means driving a completely new type of window and curtain wall product through the very conservative building channel — and that’s a daunting marketing challenge. Traditional solar modules on racks may be less than aesthetically perfect, but they have a distribution channel and a solid track record of technical expertise.

Currently, global deployment of OSCs is negligible. Global production capacity amounts to just a few megawatts. OSCs have the lowest efficiency range of any NREL-listed materials system and have not yet delivered on their commercial or cost promise.

Is the record 9.8% efficiency test performed at standard test conditions? Tell us more about the record conditions and certifier.

What efficiency do you think can be expected in a commercial product this year and next?

What cost metric can you provide? Cost-adder per square-foot?

What do you figure is the penalty on yield for vertical windows versus flat-panel PV over the course of a year?

How is power pulled off the individual windows? What is the inverter scheme?

How do you get the building trade to accept this new type of construction?

Have you started the UL process for a powered window product?

Is the entire system cost eligible for the ITC credit?

*Solar efficiency records are typically measured at one of five official test centers: NREL, AIST, PTB, Fraunhofer ISE, and ESTI. There is no category for “transparent solar cell” on the NREL PV record efficiency chart.