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425 points nixass | 15 comments | | HN request time: 1.849s | source | bottom
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DangitBobby ◴[] No.26674437[source]
What happens to reactors after 50 or 100 years of global/national decline due to environmental and geopolitical circumstances?
replies(6): >>26674489 #>>26674509 #>>26674528 #>>26674531 #>>26674716 #>>26675607 #
politician ◴[] No.26674489[source]
Would you be OK with putting the reactors on the Moon and beaming the power down to Earth?
replies(3): >>26674537 #>>26674584 #>>26674608 #
toomuchtodo ◴[] No.26674537[source]
Sure, 8 light minutes away sounds great. We’ll even get some light out of the transmission of energy to us and the waste is taken care of.
replies(1): >>26674570 #
Pfhreak ◴[] No.26674570[source]
The moon is much, much closer than 8 light minutes away. Are you thinking of the sun? It's already doing a good job at sending energy to us from nuclear reactions.
replies(1): >>26674581 #
1. toomuchtodo ◴[] No.26674581[source]
That’s the joke. The Sun is safe, cheap fusion at a distance. Enough sunlight hits the Earth in 30 minutes (I’ve seen figures as low as 2 minutes from the UAE, but am conservative for argument’s sake) to power humanity for a year.
replies(2): >>26674692 #>>26674720 #
2. kergonath ◴[] No.26674692[source]
We’re never going to cover any significant portion of the Earth with solar panels, though. And the photoelectric effect has efficiency limits.
replies(2): >>26674951 #>>26674980 #
3. politician ◴[] No.26674720[source]
Unfortunately, the same NIMBY crowd that hates nuclear also hates the idea of fields of solar cells and the idea of fields of wind farms.
replies(1): >>26674910 #
4. toomuchtodo ◴[] No.26674910[source]
And yet, renewables account for almost all new generation being turned up.

Turns out there are lots of places to install panels and turbines where there aren’t NIMBYs.

https://www.eia.gov/todayinenergy/detail.php?id=46416

replies(1): >>26675021 #
5. toomuchtodo ◴[] No.26674951[source]
Can you provide evidence why we wouldn’t or can’t? We are only limited by panel production and deployment rates. We’re not going to run out of land or raw materials.
replies(1): >>26675770 #
6. Pfhreak ◴[] No.26674980[source]
What's 'significant'? We're at the point where we are adding gigawatts of solar capacity annually. That feels significant to me.
replies(1): >>26675918 #
7. yellowapple ◴[] No.26675021{3}[source]
There are also lots of places to build nuclear power plants without NIMBYs.

Point being, NIMBYs often have a rather inflated idea of what counts as "in my back yard".

8. kergonath ◴[] No.26675770{3}[source]
For a start, 2 thirds of the Earth’s surface are oceans. Then, fields and other agricultural land is about 40% of the land surface area. And we are supposed to grow forests as carbon sinks. Then, you have mountains ranges, which might or might not be good places to put solar panels depending on a whole bunch of factors. Similarly, some deserts can be used to put solar panels, at the cost of long-range transport for the produced electricity, but a lot of them aren’t nice places for this type of installations (either very cold or with wide temperature fluctuations, harsh environment).

That’s a lot of places where we can’t. And we need to be careful where we can put them. We are causing a mass extinction event just because of how we destroy ecosystems and degrade our environment, and crop fields of pastures are much less disruptive than covering massive areas with panels.

I am not saying we don’t or should not use solar panels where it makes sense, just that using the total energy received by the Earth as a measure is not really relevant, because the land we can allocate to that will always be insignificant compared to the surface of the Earth. If you factor land use, it is clear that solar panels by themselves cannot be all of the answer.

replies(1): >>26675893 #
9. toomuchtodo ◴[] No.26675893{4}[source]
> If you factor land use, it is clear that solar panels by themselves cannot be all of the answer.

Disagree. Rebuttal: https://landartgenerator.org/blagi/archives/127

Direct img link: http://landartgenerator.org/blagi/wp-content/uploads/2009/08...

replies(1): >>26676031 #
10. kergonath ◴[] No.26675918{3}[source]
Significant compared to the Earth’s surface area and the amount of radiation we receive. Sure, we get a lot of energy from the sun. But no, we’re never going to turn more than a tiny fraction of that into electricity. The orders of magnitude just don’t match.
replies(1): >>26678665 #
11. kergonath ◴[] No.26676031{5}[source]
Right. What does it have to do with this? I pointed out that using the total radiation input on Earth as a measure is irrelevant, because we are never going to use anything close to this.
replies(1): >>26676047 #
12. toomuchtodo ◴[] No.26676047{6}[source]
Right! This demonstrates how little land mass needs to be used to power the world entirely from solar. Total solar potential is clear, total land use necessary is clear, ergo solar can power the world. Anything else is hand waving and excuses.
replies(2): >>26676579 #>>26681171 #
13. effie ◴[] No.26676579{7}[source]
> ergo solar can power the world

You forgot about clouds, nights and current lack of capability to store/transport energy to mitigate them. This can be solved but it is not trivial.

14. Pfhreak ◴[] No.26678665{4}[source]
Ok, but we don't need that much energy. Something close to 200 petawatts continuously strike the surface. Humanity uses something like 15 terawatts. To fully cover our energy needs we'd need to capture less than 1 in 10,000 watts or 0.01% of the sun's energy hitting earth. But I don't think 100% solar is anyone's goal. So we'd need to capture less than that.

So it seems to me that we could absolutely cover a significant amount of our energy use.

15. stjohnswarts ◴[] No.26681171{7}[source]
It can't in natural disasters which quickly remove solar power and we also can't store up enough power to handle peak demand in summers and winters. It's nice to act like that's not a problem when you live in some place like San Jose where it doesn't regularly get 110 or -20F