Project Name: Mini-Modules Made with Monolithically Integrated All-Perovskite Tandems
Funding Opportunity: Solar Energy Technologies Office Fiscal Year 2018 Funding Program (SETO FY2018)
SETO Research Area: Photovoltaics
Location: Boulder, CO
SETO Award Amount: $1.5 million
Awardee Cost Share: $400,000
Principal Investigator: Michael McGehee

-- Award and cost share amounts are subject to change pending negotiations --

This project team will work to increase the efficiency and durability of tandem, or two-layer, perovskite solar cells. The top and bottom layers collect higher- and lower-energy sunlight, respectively, which can increase the efficiency by which the sunlight is converted into electricity compared to single-layer cells. The team will study methods to increase the range of sunlight absorbed by the two layers. The team will also work to increase the longevity and stability of perovskite solar cells.

APPROACH

First the researchers will build single-junction perovskite solar cells that absorb certain energy ranges of sunlight and can achieve 19% efficiency. They will experiment with materials and energy ranges to lessen degradation, with the goal of retaining at least 90% of the starting efficiency after the cells have been exposed to five times the typical illumination from the sun for 1,000 hours. Then they will make tandem perovskite solar cells with at least 27% total sunlight conversion efficiency, using fabrication methods that can be scaled up for mass production. Finally, they will test that the tandem cell’s efficiency does not degrade by more than 10% after 1,000 hours of five-sun illumination.

INNOVATION

A successful increase in the energy range separation between the top and bottom layers in the solar cell will lead to efficiencies of 27% or higher in tandem perovskite solar cells. The team will test different scalable fabrication materials and methods to determine what factors lead to reduced efficiency degradation in tandem perovskite cells.