Fusion?

[pocaracas]

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

yeah... I was once that optimistic about photovoltaics... then I learned how dirty the process of creating electronics is... and photovoltaics are just silicon electronic devices... Don't get me started on rarer semiconductors.

But, there is a way: electricity generation from heat. Heat from the sun is quite easy and cheap and broadly available all over the world (but not in the UK, sorry). And that heat can power a turbine or something... But, for that to be profitable, you need a huge surface of mirrors concentrating the heat on one turbine, not something most home-owners would be able to do on their roof-tops... just something on a power plant scale.
We have a bunch of desert in northern Africa, with a lot of heat going to waste. Just think if all the countries around the Sahara were powered by desert heat.
Each time I think about the natural wealth in that continent just going to waste, due to stupid feuds among the people there.... ARGGHGHHH!