
379Energy from Space for Sustainable Commercial Power for Earth
add only approximately 15,000 t/TW
e
-y [6 (chapter 9)]. Better rectenna design
can greatly reduce the mass of support structures.
The LSP system differs from all terrestrial power systems in its effects on
earth. Reservoirs behind hydroelectric dams, farming for biomass, and large
solar arrays change earth’s reectance, usually decreasing it and increas-
ing the waste solar power that ows into the biosphere. A 20-TW
e
collection
of wind farms will have to capture approximately 10% of the wind power
that ows at low altitudes over the continents. They can potentially modify
global wi ...