Forecasts indicate that worldwide demand for new base-load electrical power generation capacity will continue to grow throughout the twenty-first century. However, evidence is mounting to show that the use of fossil fuels—coal, oil, and natural gas—and the resulting increase in greenhouse gas emissions may be leading to measurable global climate change. New energy technologies are needed to offset the future growth in fossil fuel use.

One concept that would provide power on a significant scale for global markets is energy from space. Earth is about 150 million kilometers (93 million miles) from the Sun. Sunlight constantly delivers 1,358 watts of energy per square meter of area to the part of Earth facing the Sun. However, by the time the sunlight reaches the surface of Earth, atmospheric filtering has removed about 30 percent of the initial energy even on a clear day. Moreover, the effects of the...