Re: GURPS O'Neill Cylinder Design
 

A lot of futuristic settings are over populated and/or have expansive nature preserves. Either of those would make reduced land area required for power quite desirable.

Re: GURPS O'Neill Cylinder Design
 

I understand that you can used the land under a large microwave rectenna for other purposes, as the rectennas are rather open structures and block little rain or sunlight, and are light enough to suspend well above the ground.

Re: GURPS O'Neill Cylinder Design
 

... if you have enough power sats you can redirect them to all aim at the same place, can't you?

Re: GURPS O'Neill Cylinder Design
 

If individually you had powersats that could deliver energy in concentrations equal to half of sunlight (though in longer wavelengths) aiming 10 powesats at the same area would enable you to boil water 5x as fast as leaving it out in normal sunshine.

Giant death rays are actually quite hard to build.

Re: GURPS O'Neill Cylinder Design
 

It would actually be decently dangerous, but so is taking control of the power supply of a small country...

Re: GURPS O'Neill Cylinder Design
 

I remember a scene in one novel, where the protagonists are moving through a rectenna's 'shade' and it's being used as grazing for cows.

Re: GURPS O'Neill Cylinder Design
 

The best use is vegetable and fruit crops actually. The wire mesh can be placed 8' above the ground and they absorb ~100% of the microwaves, though only 80% gets turned into electricity (20% into waste heat). With the waste heat, you can grow vegetables and fruits outside of their normal growing season (while you could also do it with grains, grains are less profitable than vegetables and fruits).

Re: GURPS O'Neill Cylinder Design
 

Depending on the design, you might not be able to fit harvesters between the rectenna supports, and people might be unwilling to work under them, for fear of being 'nuked', no matter the truth of the matter. Also, you can run cattle on land that's unsuitable for market gardens (and sheep on even worse land).

The point is, you can get dual-use out of the land by farming it with whatever works best on that land as well as having the rectenna converting microwaves to power.

Re: GURPS O'Neill Cylinder Design
 

I have an unplaceable memory of a story in which there was a coffee plantation under a power rectenna, which with the rectenna itself concealed some sort of villainous facility from observation.

Re: GURPS O'Neill Cylinder Design
 

I would avoid uses that run the risk of maintenance issues for the rectenna structure. Depending on the opacity of the rectenna, I might put a conventional solar farm under it -- there's some loss of efficiency because of light blocked by the rectenna, but you make up for it with simplifying your power grid.