The Center's vision and long-term goal is to help make photovoltaic (PV) electricity a major source of energy. To accomplish this, the Center is developing new strategies for bringing cost down and efficiency up, with a target of $1/W. Research focuses on inexpensive thin film semiconductors that can be processed using high throughput schemes. This includes CdTe and CIGS, as well as new thin film alternatives like MgxCd1-xTe, CZTS, and pyrite (FeS2). Processing strategies involve both state-of-the-art gas phase and exploratory solution-based methods.
At the moment, the manufacturing cost of single junction cells (i.e., CdTe) is approaching $0.5/W, but the cost of PV systems remains high ($2.5/W) because the relatively low efficiency (~12%) leads to high balance of system (BOS) costs. A new technology with the very low manufacturing cost of CdTe but with significantly higher efficiency (>20%) is needed to significantly reduce the cost of PV electricity to $1/W and make it competitive with fossil fuels. This is a tremendous challenge, and no such technology currently exists that can meet this need. It is not simply a matter of improving existing commercially available technologies. A new approach is needed.
The Center for Next Generation Photovoltaics is working to develop such an approach through cooperation between academic researchers and industrial partners. We believe that the most viable way to achieve these goals is through the development of multijunction thin film solar cells. Extremely high efficiency multijunction (or tandem) solar cells already exist and can be made by ultrahigh vacuum deposition of predominantly III-V semiconductors with efficiencies exceeding 40%. But cells made in this way, using these materials, are limited to very small size and exceedingly high manufacturing cost. They are widely used in space applications which require their high efficiency, but are not suitable for terrestrial applications because of their very prohibitively high cost. A multijunction cell that could be produced as inexpensively as a thin film CdTe solar cell, by depositing thin film semiconductor materials on very large area substrates, and achieve efficiencies exceeding 20%, would revolutionize the PV industry.
With this overarching theme, the Center focuses on developing both new and established low-cost thin film materials to achieve an ultrahigh efficiency thin film multijunction solar cell. At the moment, it is not clear which materials are best suited for this, so research in the Center involves the study of a variety of materials, keeping in mind performance, cost, availability, environmental impact and manufacturability. New processing strategies with unexplored combinations of materials are needed. Therefore, research involves several different approaches, including gas-phase and solution-phase methods, but all are targeted on achieving high throughput, large area devices and low cost.
Research that will position industry partners with new intellectual property that provides a fundamental competitive advantage in the future is a primary consideration.
Interested in joining the Center? See the Membership Information page for details.
