Both manned and unmanned off-Earth missions of the future will require very lightweight, inexpensive, high efficiency, flexible and single-use photovoltaic (PV) arrays to generate electric power. Current PV technology horizons do not meet the requirements for expanded mission capability. Although inorganic PVs hold the record for solar power conversion efficiency, they are inflexible, heavy, and expensive to produce. There is increasing interest in a new type of PV technology that is based on organic semiconducting materials. However, the performance of these devices has been limited by the availability of stable n-type (acceptor) organic semiconductors. TDA Research, Inc. proposes to use a new class of n-type conjugated polymers to produce more efficient organic PV devices (OPVs). The first generation of our new acceptor materials is already commercially available through Sigma-Aldrich, and the current technology readiness level (TRL) at the end of the Phase I stands at 4 with proof-of-concept results, OPV prototypes, and commercial sales. A successful Phase II project will lead to several commercial n-type organic semiconductor products being sold by Sigma-Aldrich to both the research and commercial markets, and the use of our products in the full scale production of lightweight flexible OPVs (TRL 6-7).