We need nuclear-powered airplanes, Kevin Bullis argues, not solar-powered ones:
There are some things solar panels are good for, but they’re not good for passenger aircraft. The energy in sunlight is too diffuse. A square-meter solar panel generates less than 200 watts in full sunshine. In comparison, a small, half-meter-wide, gasoline-powered generator can generate 3,500 watts. It can run for 24 hours — at half power — on less than 12 gallons of fuel. The solar panel, of course, stops working at night. If it can generate some extra power during the day, that could be stored in batteries. But batteries store only about 1/100th as much energy as gasoline.
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The lowest carbon route could be making fuels from carbon dioxide and water using energy from land-based solar power or nuclear power plants. Eventually high temperature nuclear power plants now in development might be an even better option — their heat could be used to facilitate the necessary chemical reactions more efficiently than electricity could.