Some 30 years ago NASA came up with another BIG idea. Assemble vast solar electric arrays in space and beam the energy to earth. The environmental community did not dismiss NASA’s vision out of hand. After all, the sun shines 24 hours a day in space. A solar cell on earth harnesses only about four hours equivalent of full sunshine a day. If renewable electricity could be generated more cheaply in space than on earth, what’s the problem?

A number of us argued that the problem was inherent in the scale of the power plant. Whereas rooftop solar turns us into producers, builds our self-confidence and strengthens our sense of community as we trade electricity back and forth with our neighbors, space-based solar arrays aggravate our dependence. Continue reading