Fusion?

[BrianSoddingBoru4]

We already HAVE a fully functional fusion reactor.



Boru

Indeed.... but how to harness all that power?
https://en.wikipedia.org/wiki/Dyson_sphere

The grand thing is, we don't have to harness all of it. Attend:

The sun produces (roughly) 3.8 x 10^27 joules of energy every second. World energy consumption is on the close order of 6 x 10^20 joules per year. Obviously a lot of what the sun produces is (from our perspective) wasted - only around 2 billionths of what the sun produces gets to us. But that translates into the Earth receiving about as much energy every second as the world uses in a year.

Rounding down, there are about 30 million seconds in a year. Thus, if we converted 1/30 000 000th of available sunlight into usable power every year, we'd be set until the dear old Sol burns herself out (not that we're going to last that long, anyroad).

We don't know how to make fusion workable. We don't know how to build Dyson Spheres (or even Niven-esque Ringworlds). But we DO know how to turn sunlight into electricity. Solar powering our planet won't be easy, but it is really just a problem of scale. The others are problems that are possibly insoluble from a technological standpoint.

Boru