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From time to time I read about putting solar panels in space, where they will collect more energy, not use up the limited surface area of our planet, and (thanks to orbital geometry) power our lives at night as well as day.
[ If we had a fat enough wire going around the world, we could use terrestrial solar to power the night-time hemisphere too. ]
Sunlight on Earth is safeish.
In the UK six people a day die from skin cancer; as far as I can determine most of these are caused by exposure to sunlight.
If I went to the tropics and exposed my whole body to the sun I would get sunburnt and regret it within a day.
If an energy beam is weaker than sunlight, isn't it going to need as much receiving equipment as terrestrial solar ?
Put another way, if the beam is twice as energy-dense as the sun we are only going to halve the ground area we need to devote to solar panels or radio meshes or whatever.
So we can beam energy down from space without frying everything in its path, but we are working in the safety margin; if something goes wrong, a member of the public could be inconvenienced unless they were already avoiding legitimate activities.
Maybe some other sort of beam is safer than sunlight ?
If so we can have a more concentrated energy beam that people can more safely walk through.
Microwaves cook my tea, so I doubt that a megajoule of microwaves will do an order of magnitude less damage to my body than a megajoule of sunlight.
It seems to me that a focused beam is too big a risk.
While a diffuse beam could be technically safe, a system that was socially acceptable is unlikely to be a financial improvement on solar panels - even if the energy put into the beam cost nothing.
Clouds block sunlight and u/v; what sorts of radiation do they allow through ? Do we have better protection against this and does a constant supply give a greater energy yield ?
What have I missed ?
[ If we had a fat enough wire going around the world, we could use terrestrial solar to power the night-time hemisphere too. ]
Sunlight on Earth is safeish.
In the UK six people a day die from skin cancer; as far as I can determine most of these are caused by exposure to sunlight.
If I went to the tropics and exposed my whole body to the sun I would get sunburnt and regret it within a day.
If an energy beam is weaker than sunlight, isn't it going to need as much receiving equipment as terrestrial solar ?
Put another way, if the beam is twice as energy-dense as the sun we are only going to halve the ground area we need to devote to solar panels or radio meshes or whatever.
So we can beam energy down from space without frying everything in its path, but we are working in the safety margin; if something goes wrong, a member of the public could be inconvenienced unless they were already avoiding legitimate activities.
Maybe some other sort of beam is safer than sunlight ?
If so we can have a more concentrated energy beam that people can more safely walk through.
Microwaves cook my tea, so I doubt that a megajoule of microwaves will do an order of magnitude less damage to my body than a megajoule of sunlight.
It seems to me that a focused beam is too big a risk.
While a diffuse beam could be technically safe, a system that was socially acceptable is unlikely to be a financial improvement on solar panels - even if the energy put into the beam cost nothing.
Clouds block sunlight and u/v; what sorts of radiation do they allow through ? Do we have better protection against this and does a constant supply give a greater energy yield ?
What have I missed ?
