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Can someone explain something about fusion for me? To make a fusion reactor that's useful you have to solve two problems: First you have to build a working fusi

Can someone explain something about fusion for me? To make a fusion reactor that's useful you have to solve two problems: First you have to build a working fusion reactor. Second, you have to capture that energy to do useful work. Given that, wouldn't it make more sense to focus on technology to capture energy from the giant, already working fusion reactor in the sky?

alexchamberlain 5y ago
The giant fusion reactor in the sky dissipates most of its energy before it gets to Earth, and more of it in the atmosphere. A new star born in a reactor can be fully contained, so most of its energy can be captured for its intended use case.
space_fountain 5y ago
A fusion reactor could have much more concentrated energy. The sun is great, but it's putting out energy in all directions and we're a long way away
thescriptkiddie 5y ago
Solar panels are all well and good, but you couldn't use them inside of a fusion reactor. For one thing they wouldn't be able to withstand the temperature and neutron flux. Most fusion reactor designs capture energy by heating water, same as a fission reactor.
300bps 5y ago
We generate electricity with fusion the same way we do with many other technologies. We heat up water until it turns to steam which moves a turbine to spin some magnets to generate electricity. Fusion’s advantage over solar is it can theoretically generate unlimited energy in a relatively small footprint. It also doesn’t go out 8-12 hours per day. But I think the reality is that we need to pursue many options for clean energy.
zulban 5y ago
In addition to what others have said, the sun isn't always in the sky.
- mikeyouse 5y ago
  I'd like to see a side-by-side... The sun is always in the sky, just not where power is needed. If you look at the global investment into fusion, I wonder by what order of magnitude that compares to scrapping that work and building HVDC lines East-West to major population centers and North-South to places with super-high availability wind resources. We could basically build those "tomorrow" as compared to spending billions/year in research and then tens of billions/year in actual construction cost when we figure out the technology. Not a 'fair' comparison by any stretch but I think it'd be interesting.
spdegabrielle 5y ago
The economics don’t make sense. Everyone has access to the sun. Even in poor countries.
- noah_buddy 5y ago
  What an incredibly cynical take. Perhaps if abundant and easy to harvest free energy existed in the sky, we would have abundant cheap ways to capture it? The issues are more profound than rich people want to keep the poor people down.
lkbm 5y ago
Thirty years ago it would have been true to say "Solar is decades away from being viable as our primary energy source, whereas fission has been ready and able for decades." I really wish we'd gone with Nixon's 1970s proposal to make our entire grid carbon-neutral using fission, but given how the politics of that worked out, I'm also incredibly grateful that people kept working on photovoltaic technology anyway. We're building out solar pretty rapidly, and the technology has been advancing at an incredible rate, but we can work on multiple solutions simultaneously, and solar is a clear case study in why working on not-yet-viable technology is incredibly worthwhile pursuit.

alexchamberlain 5y ago

The giant fusion reactor in the sky dissipates most of its energy before it gets to Earth, and more of it in the atmosphere. A new star born in a reactor can be fully contained, so most of its energy can be captured for its intended use case.

space_fountain 5y ago

A fusion reactor could have much more concentrated energy. The sun is great, but it's putting out energy in all directions and we're a long way away

thescriptkiddie 5y ago

Solar panels are all well and good, but you couldn't use them inside of a fusion reactor. For one thing they wouldn't be able to withstand the temperature and neutron flux. Most fusion reactor designs capture energy by heating water, same as a fission reactor.

300bps 5y ago

We generate electricity with fusion the same way we do with many other technologies. We heat up water until it turns to steam which moves a turbine to spin some magnets to generate electricity. Fusion’s advantage over solar is it can theoretically generate unlimited energy in a relatively small footprint. It also doesn’t go out 8-12 hours per day. But I think the reality is that we need to pursue many options for clean energy.

zulban 5y ago

In addition to what others have said, the sun isn't always in the sky.

mikeyouse 5y ago
I'd like to see a side-by-side... The sun is always in the sky, just not where power is needed. If you look at the global investment into fusion, I wonder by what order of magnitude that compares to scrapping that work and building HVDC lines East-West to major population centers and North-South to places with super-high availability wind resources. We could basically build those "tomorrow" as compared to spending billions/year in research and then tens of billions/year in actual construction cost when we figure out the technology. Not a 'fair' comparison by any stretch but I think it'd be interesting.

spdegabrielle 5y ago

The economics don’t make sense. Everyone has access to the sun. Even in poor countries.

noah_buddy 5y ago
What an incredibly cynical take. Perhaps if abundant and easy to harvest free energy existed in the sky, we would have abundant cheap ways to capture it? The issues are more profound than rich people want to keep the poor people down.

lkbm 5y ago

Thirty years ago it would have been true to say "Solar is decades away from being viable as our primary energy source, whereas fission has been ready and able for decades." I really wish we'd gone with Nixon's 1970s proposal to make our entire grid carbon-neutral using fission, but given how the politics of that worked out, I'm also incredibly grateful that people kept working on photovoltaic technology anyway. We're building out solar pretty rapidly, and the technology has been advancing at an incredible rate, but we can work on multiple solutions simultaneously, and solar is a clear case study in why working on not-yet-viable technology is incredibly worthwhile pursuit.