This Small Business Innovation Research Phase (SBIR) I project aims to develop a new class of solar cell based on an internal photoemission device geometrically configured as a near perfect, broadband, isotropic absorber. Realizing the potential of this technology would bring to market a solar cell that is commercially competitive with other solar technologies on a cost per watt basis and are able to fabricated on a flexible substrate. Internal photo-emission converters have received renewed interest, but published power conversion efficiencies are well below the theoretical limit. A primary limiting factor in previous attempts has been limited light absorption in the metal. Our preliminary simulations and tests show enhanced light absorption across a broad range of angles and wavelengths when the absorbing metal is configured in a nanocomposite layer in a perfect absorber structure. The objective of Phase I is to validate the preliminary simulations by fabricating and testing a functioning device.
The broader impact/commercial potential of this project is primarily in the field of solar energy conversion. Successful completion of Phase I and Phase II of this research and development effort will enable commercialization of a low cost and long lifetime solar cell technology that can be manufactured on a flexible substrate using roll-to-roll processing techniques. This technology will provide a new cost competitive entry into the flexible and conformable solar cell market.
PI Energy has designed built, tested, and characterized a new class of solar cell that is based on a plasmonic absorber that converts incident sunlight to electric current via internal photo-emission. The technology is one tenth to one hundredth thinner than existing solar photovoltaics and uses common non-toxic materials. The device can be made with low capital cost equipment that is currently available and is easily scalable to GW levels. The technology has potential to be less than one tenth the solar cell level cost of existing solar technology. Under the NSF phase I grant, we built multiple working prototypes that produced power, electrically tested them using a solar simulator. In addition we built larger solar cells to demonstrate the ability to produce devices that can be used as commercial devices. We performed a production cost analysis as well as developed a commercialization plan. In phase II we plan to improve efficiencies and build units for a pilot demonstration as well as test the devices for reliability. The solar PV market is currently a $93 billion dollar market. A dramatic decrease in the cost of solar PV would increase the solar energy market size and increase adoption of solar PV.
