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It is currently fashionable for farmers to plead "global
warming" as an excuse to convert tens of acres of farmland
into giant arrays of solar panels.
It is true that these apparati generate electricity without
directly burning fossil fuel. In some cases, they may even
generate enough to
offset the carbon footprint of installing
them, and even to exceed the carbon that would have been
fixed by the perfectly adequate plants that used to be there.
However, all the electricity they generate ends up as heat
sooner or later. Indeed, if solar panels do their job by
absorbing almost all the incoming sunlight, they are just
lowering the overall albedo of the planet. This could be
avoided if the solar panels were white, but then they woudn't
work.
The solution, really, is obvious. All the output from solar
farms needs to be fed directly to vast arrays of LEDs mounted
on parabolic reflectors that send their light out into space.
The wavelength can be chosen to be least absorbed by the
atmosphere on the way out. In this way, we actually increase
the effective albedo of the planet.
This is the ideal use for solar-generated electricity, because it
can cope with the hourly, daily and seasonal variation in
output from the solar panels without causing any
inconvenience.
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Annotation:
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This could get too popular, and people would end up useing the subsidies to power these spotlights with nucular or coal-fired power stations |
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I'm sure there'd be some way to finesse that particular
problem. |
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A quick calculation tells me that if we can produce a steady
1 million Gigawatts of light and send it spacewards, we
offset 1% of all the solar energy reaching Earth, which ought
to cool things down quite a lot. The biggest solar farms at
the moment produce about 0.5GW, so a few million of these
dotted around the globe would solve the whole problem. |
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Just to tart it up a bit: There are frequency doubling crystals. Finding one that turns IR into visible, then beaming that into space could be done without the electricity part. |
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Using parabolic mirrors and a smaller crystal would likely be possible, cheaper, and more effective than crystal coated mirrors. |
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There is something called the urban heat island effect, where cities warm up more from (I think) absorption of light. Putting these mirror crystals on city rooftops could beneficially lower city temperatures. Now for somebody to actually do the numbers... |
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Nice idea, but which village idiot gets to keep their hand on the albedo dial? Ever notice the hysteresis loop from the thermostat dial competition? |
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Well, I think a global vote on "a nice comfortable
temperature" ought to produce a consensus, or at least a
working average. My guess is that it would come out
somewhere about 23-26°C, and we should just site these
spotlights to bring everywhere to that temperature. It'd be a
bit tough on the polar bears but, you know, fuck 'em. |
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I think instead of rating solar panels by kilowatts
they should be measured by their ability to
generate
warm fuzzy feelings and government funding. |
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Wonder if a nuclear power promotion program with
the slogan "Nuke _____ (insert city name here)!"
would get people's attention. The small print
would go on to say how many trillions of kilowatt
hours have been safely provided for tens of
millions of people over the years. |
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Instead of a nice comfortable temperature everywhere, what about a gradient so you can pick your favorite city based on the temperature... never mind, I think we have come full circle. |
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// frequency doubling crystals. Finding one that turns IR into visible // |
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Frequency doubling crystals only work with extremely low-entropy light. With thermal or blackbody radiation, it simply doesn't work. |
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// frequency doubling crystals// A massive stretch of the meaning of crystal but those green wavy fractal things, that are being replaced by concrete and tarmac, more than double. They work in bright light but need periodic darkness. |
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Gr. "this apparatus": "apparatus" is generally a non-count noun
(like "water"), not used in the plural. And, if you do force it into
the plural for your own twisted purposes, I'm pretty sure it's
fourth declension, so it doesn't have a plural in -i. Compare
"status". |
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How much of this simply heats up the atmosphere?
Keeping the beam narrow, like a powerful laser
perhaps, seems like the ticket. |
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While you're beaming that much energy into space,
might as well make some use out of it with it as the
propulsion of
a space elevator. |
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So, it sounds like the goal of global humanity is to use as much solar energy as possible, in the most complex path, leaking as little heat as possible. |
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A lot of rocket fuel production, might be possible. Possibly pushing against the grain with nuclear physics. |
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