Photovoltaic Cells for Very High Altitude Very Long Endurance Solar Aircraft

Award Information
Agency: Department of Defense
Branch: Defense Advanced Research Projects Agency
Contract: W31P4Q-09-C-0228
Agency Tracking Number: 07SB2-0613
Amount: $1,361,630.00
Phase: Phase II
Program: SBIR
Awards Year: 2009
Solicitation Year: 2007
Solicitation Topic Code: SB072-043
Solicitation Number: 2007.2
Small Business Information
4Power LLC
PO Box 416, Windham, NH, 03087
DUNS: 800129160
HUBZone Owned: N
Woman Owned: N
Socially and Economically Disadvantaged: N
Principal Investigator
 Arthur Pitera
 Senior Research Scientist
 (617) 549-4623
 apitera@4powerllc.com
Business Contact
 Eugene Fitzgerald
Title: Member, Co-Founder
Phone: (603) 275-0861
Email: eafitz@4powerllc.com
Research Institution
N/A
Abstract
This proposed Phase II program will deliver a lightweight triple-junction solar cell that eliminates the current-matching bottleneck of current state-of-the-art InGaP/GaAs/Ge cells on Ge. This will be achieved by constructing a triple junction structure on the lattice constant of SiGe, allowing the integration of semiconductors with bandgaps that are optimized for the best possible triple-junction efficiency. The cell design proposed for Phase II has a practical achievable efficiency of 47% (AM1.5 spectrum without concentration), far exceeding the current record of 32% for the same illumination conditions. III-V cell development on the SiGe lattice constant is a natural direction for 4Power’s substrate platform which already utilizes SiGe graded buffers. This strategy for optimized solar cell efficiency is fully compatible with our Si-encapsulated cell technology demonstrated in Phase I. The multijunction cell that will be developed in Phase II will incorporate both Si encapsulation and uniquely accessible optimum bandgap profiles such that high volume/low cost production of ultra-high specific power cells in a Si-compatible manufacturing environment is enabled.

* information listed above is at the time of submission.

Agency Micro-sites

SBA logo
Department of Agriculture logo
Department of Commerce logo
Department of Defense logo
Department of Education logo
Department of Energy logo
Department of Health and Human Services logo
Department of Homeland Security logo
Department of Transportation logo
Environmental Protection Agency logo
National Aeronautics and Space Administration logo
National Science Foundation logo
US Flag An Official Website of the United States Government