The productive efficiency potential of solar power vis‐a‐vis five other electric generation technologies is examined as a prototype analysis. Environmental externalities are considered as a fundamental component of the problem. The analysis is completed by the modern operations research method Data Envelopment Analysis (DEA). Lunar solar power (LSP) is shown to be considerably more efficient than fossil, nuclear, and solar terrestrial alternatives. This relationship holds even if resource costs are much greater than estimated. ©American Institute of Physics 1995