7 ms·

Technology is progressing so fast that something like space based solar or fusion power will replace terrestrial solar within 100 years.

by nroets 2y ago

stavros 2y ago
Why? When will it be cheaper to deploy in space than in some remote area somewhere?
- ExoticPearTree 2y ago
  I'm pretty sure someone will figure out how to make a working solar sail that captures energy and beams it to earth via microwaves. Please enough of them far away from Earth and you get pretty much unlimited energy all year round.
  - stavros 2y ago
    You get the same if you place solar panels in places around the equator, without all the messiness of orbital repairs and GW death rays. I can't see this being cheaper than just some panels on the ground.
    - eru 2y ago
      Why would you want to do orbital repairs? For the amount of effort required, you'd just send up a replacement.
      - stavros 2y ago
        And we're saying that deploying new solar sails (with integrated power transmitters) to orbit is cheaper than replacing a solar panel on earth?
        eru 2y ago
        Not at the moment, but at some point it might be. Real estate on earth has lots of competing uses, so it has a lot of opportunity costs.
    - adrianN 2y ago
      The death ray might be the feature that sells the whole thing.
      - stavros 2y ago
        I like the way you think.
    - ExoticPearTree 2y ago
      The funny thing about solar panels is that they are the most efficient at very low temperatures. They'd be more efficient at the poles or high up in the mountains where they can be kept cool. A solar panel in space would be highly efficient.
  - Aachen 2y ago
    Inventing the Dyson Sphere one step at a time
  - eru 2y ago
    Eventually, the limiting factor will be how to get rid of the waste heat. Even if you can turn 100% of the energy you received from space into electricity, in the end it'll all turn to heat.
    - BobaFloutist 2y ago
      Ok, so we get a really big heat pump that sends all the heat to space.
      - eru 2y ago
        If only thermodynamics was this easy. Heat pumps ain't magic, alas, they are still subject to physical limitations, including the laws of thermodynamics. Also keep in mind that cooling the hot part of your space heat pump is very limited: there's no convection nor conduction in space. You can only lose heat energy via radiation or ablation (= shooting away hot pieces).
    - ExoticPearTree 2y ago
      Waste heat from microwave energy? Am I missing something?
      - eru 2y ago
        I'm talking about waste heat from when you use the electricity. Almost no matter what machine you are powering, be it a a toaster or a computer or an electric car or a washing machine, eventually turns all of the electric energy into heat. (You can contrive some counter-examples. Eg if you point a sufficiently strong laser pointer at the sky, some of the energy will escape earth before turning into heat here.)
- eru 2y ago
  > Why? When will it be cheaper to deploy in space than in some remote area somewhere? When land becomes the limiting factor on earth.
  - mschuster91 2y ago
    Land will never become the limiting factor on earth, at least not for solar power. Assuming the worst-case predictions of climate change come true, there will be more than enough desert capacity along the equatorial areas to provide power for the rest.
    - eru 2y ago
      > Land will never become the limiting factor on earth, at least not for solar power. What makes you think so? There's always more you can do with more energy. 'Never' is a long time. And there are opportunity costs from other uses you could put land on earth to. You are right that it will be a while before remote corners on earth become more expensive than space for solar power generation. But not 'never'. (Btw, if you think really big, the limit for how much power we can use on earth is given by how much waste heat we can radiate into space. At some point, you don't want to keep beaming down energy from space into earth, even if you somehow could convert 100% of the received power into electricity with no losses: because at the end all the electrical power used will still turn into heat. Heat that we will have to get rid of. At that point in time, you might want to use the electricity directly in space, eg to run data centres there, and just beam the results of the computations down.) > Assuming the worst-case predictions of climate change come true, there will be more than enough desert capacity along the equatorial areas to provide power for the rest. While climate change might become unpleasant, I have no clue what it has to do with any of this? The surface of the earth will stay roughly constant and so will its orbit, and the sun will shine regardless of what happens on earth. (And I assume that if you wanted to badly enough, you could easily float solar panels on top of the ocean; at least easier than blasting them into space.)
      - mschuster91 2y ago
        > What makes you think so? There's always more you can do with more energy. 'Never' is a long time. And there are opportunity costs from other uses you could put land on earth to. The entire world's power supply could be met by sacrificing just 3.27% of the US [1]. The Sahara desert is already economically useless as it is completely and utterly inhospitable, unable to support life beyond a few shrubs, insects and felines. > While climate change might become unpleasant, I have no clue what it has to do with any of this? Simple, the amount of desertified space will grow, and so space that is now unusable for solar power because it can actually be used at the moment can then be used for power. [1] https://www.axionpower.com/knowledge/power-world-with-solar/ https://www.axionpower.com/knowledge/power-world-with-solar/
audunw 2y ago
Space based solar might not take a form where we just put mirrors in space to boost the output of existing terrestrial solar cells. The benefit is that the receivers on the ground can receive energy directly from the sun when the sun is up, and the space mirrors can be used to provide light to areas that are completely dark in winter. I don’t think microwave beaming is ever viable Most fusion concepts are thermal power plants. Those have inherent downsides that have nothing to do with the nuclear energy providing the heat for the steam turbines. So they will never fully replace renewables. Helion’s concept might work. But that remains to be seen.
- closewith 2y ago
  What would those downsides be?
  - adrianN 2y ago
    Steam turbines alone are more expensive than solar.
- lazide 2y ago
  Space based solar (lens or microwave) is a non starter for one simple reason - it would be an ideal supervillain weapon to anyone who could steer it.
  - lolc 2y ago
    The station couldn't be used as a threat. And its use would be very limited in time. Taking out the rogue orbital power station would be a competition between very trigger happy militaries. Who wouldn't want to demonstrate their satellite killers on a legitimate target?
    - lazide 2y ago
      Anything which could transmit meaningful power to the ground is going to have no issue destroying anything approaching it from below. And why wouldn’t one of those powers be the ones installing such an installation in the first place?
nsonha 2y ago
Once we start making these predictions with no single one of such project even planned, then people start predicting about all sort of bat shit crazy ideas "within the next 100 years" and there is no philosophical razor we can employ to discern them from the legit ones.
- quitit 2y ago
  I've read "in 100 years" about many technologies that we'd supposedly have in our current era. It's an often used qualifier to dodge what can turn out to be meritless predictions. Just long enough into the future to sound promising, but also far enough into the future to not tempt a need for supporting evidence. In my view if we don't have the underpinnings or motivation today to support such forward looking statements, then there is no genuine foundation for claiming that the situation will improve merely as time moves on. Technology only comes about when we make it, and only develops rapidly when there is a significant motivation for putting serious manpower behind it. One could just as easily say that we'll have small and portable fusion reactors that completely satisfy our energy needs.

Technology is progressing so fast that something like space based solar or fusion power will replace terrestrial solar within 100 years.

by nroets 2y ago

Technology is progressing so fast that something like space based solar or fusion power will replace terrestrial solar within 100 years.

stavros 2y ago

Why? When will it be cheaper to deploy in space than in some remote area somewhere?

ExoticPearTree 2y ago
I'm pretty sure someone will figure out how to make a working solar sail that captures energy and beams it to earth via microwaves. Please enough of them far away from Earth and you get pretty much unlimited energy all year round.
- stavros 2y ago
  You get the same if you place solar panels in places around the equator, without all the messiness of orbital repairs and GW death rays. I can't see this being cheaper than just some panels on the ground.
  - eru 2y ago
    Why would you want to do orbital repairs? For the amount of effort required, you'd just send up a replacement.
    - stavros 2y ago
      And we're saying that deploying new solar sails (with integrated power transmitters) to orbit is cheaper than replacing a solar panel on earth?
      - eru 2y ago
        Not at the moment, but at some point it might be. Real estate on earth has lots of competing uses, so it has a lot of opportunity costs.
  - adrianN 2y ago
    The death ray might be the feature that sells the whole thing.
    - stavros 2y ago
      I like the way you think.
  - ExoticPearTree 2y ago
    The funny thing about solar panels is that they are the most efficient at very low temperatures. They'd be more efficient at the poles or high up in the mountains where they can be kept cool. A solar panel in space would be highly efficient.
- Aachen 2y ago
  Inventing the Dyson Sphere one step at a time
- eru 2y ago
  Eventually, the limiting factor will be how to get rid of the waste heat. Even if you can turn 100% of the energy you received from space into electricity, in the end it'll all turn to heat.
  - BobaFloutist 2y ago
    Ok, so we get a really big heat pump that sends all the heat to space.
    - eru 2y ago
      If only thermodynamics was this easy. Heat pumps ain't magic, alas, they are still subject to physical limitations, including the laws of thermodynamics. Also keep in mind that cooling the hot part of your space heat pump is very limited: there's no convection nor conduction in space. You can only lose heat energy via radiation or ablation (= shooting away hot pieces).
  - ExoticPearTree 2y ago
    Waste heat from microwave energy? Am I missing something?
    - eru 2y ago
      I'm talking about waste heat from when you use the electricity. Almost no matter what machine you are powering, be it a a toaster or a computer or an electric car or a washing machine, eventually turns all of the electric energy into heat. (You can contrive some counter-examples. Eg if you point a sufficiently strong laser pointer at the sky, some of the energy will escape earth before turning into heat here.)
eru 2y ago
> Why? When will it be cheaper to deploy in space than in some remote area somewhere? When land becomes the limiting factor on earth.
- mschuster91 2y ago
  Land will never become the limiting factor on earth, at least not for solar power. Assuming the worst-case predictions of climate change come true, there will be more than enough desert capacity along the equatorial areas to provide power for the rest.
  - eru 2y ago
    > Land will never become the limiting factor on earth, at least not for solar power. What makes you think so? There's always more you can do with more energy. 'Never' is a long time. And there are opportunity costs from other uses you could put land on earth to. You are right that it will be a while before remote corners on earth become more expensive than space for solar power generation. But not 'never'. (Btw, if you think really big, the limit for how much power we can use on earth is given by how much waste heat we can radiate into space. At some point, you don't want to keep beaming down energy from space into earth, even if you somehow could convert 100% of the received power into electricity with no losses: because at the end all the electrical power used will still turn into heat. Heat that we will have to get rid of. At that point in time, you might want to use the electricity directly in space, eg to run data centres there, and just beam the results of the computations down.) > Assuming the worst-case predictions of climate change come true, there will be more than enough desert capacity along the equatorial areas to provide power for the rest. While climate change might become unpleasant, I have no clue what it has to do with any of this? The surface of the earth will stay roughly constant and so will its orbit, and the sun will shine regardless of what happens on earth. (And I assume that if you wanted to badly enough, you could easily float solar panels on top of the ocean; at least easier than blasting them into space.)
    - mschuster91 2y ago
      > What makes you think so? There's always more you can do with more energy. 'Never' is a long time. And there are opportunity costs from other uses you could put land on earth to. The entire world's power supply could be met by sacrificing just 3.27% of the US [1]. The Sahara desert is already economically useless as it is completely and utterly inhospitable, unable to support life beyond a few shrubs, insects and felines. > While climate change might become unpleasant, I have no clue what it has to do with any of this? Simple, the amount of desertified space will grow, and so space that is now unusable for solar power because it can actually be used at the moment can then be used for power. [1] https://www.axionpower.com/knowledge/power-world-with-solar/ https://www.axionpower.com/knowledge/power-world-with-solar/

audunw 2y ago

Space based solar might not take a form where we just put mirrors in space to boost the output of existing terrestrial solar cells. The benefit is that the receivers on the ground can receive energy directly from the sun when the sun is up, and the space mirrors can be used to provide light to areas that are completely dark in winter. I don’t think microwave beaming is ever viable Most fusion concepts are thermal power plants. Those have inherent downsides that have nothing to do with the nuclear energy providing the heat for the steam turbines. So they will never fully replace renewables. Helion’s concept might work. But that remains to be seen.

closewith 2y ago
What would those downsides be?
- adrianN 2y ago
  Steam turbines alone are more expensive than solar.
lazide 2y ago
Space based solar (lens or microwave) is a non starter for one simple reason - it would be an ideal supervillain weapon to anyone who could steer it.
- lolc 2y ago
  The station couldn't be used as a threat. And its use would be very limited in time. Taking out the rogue orbital power station would be a competition between very trigger happy militaries. Who wouldn't want to demonstrate their satellite killers on a legitimate target?
  - lazide 2y ago
    Anything which could transmit meaningful power to the ground is going to have no issue destroying anything approaching it from below. And why wouldn’t one of those powers be the ones installing such an installation in the first place?

nsonha 2y ago

Once we start making these predictions with no single one of such project even planned, then people start predicting about all sort of bat shit crazy ideas "within the next 100 years" and there is no philosophical razor we can employ to discern them from the legit ones.

quitit 2y ago
I've read "in 100 years" about many technologies that we'd supposedly have in our current era. It's an often used qualifier to dodge what can turn out to be meritless predictions. Just long enough into the future to sound promising, but also far enough into the future to not tempt a need for supporting evidence. In my view if we don't have the underpinnings or motivation today to support such forward looking statements, then there is no genuine foundation for claiming that the situation will improve merely as time moves on. Technology only comes about when we make it, and only develops rapidly when there is a significant motivation for putting serious manpower behind it. One could just as easily say that we'll have small and portable fusion reactors that completely satisfy our energy needs.