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If they can get a continuous fusion reaction going converting the heat energy from that to electricity won't be a problem. Getting a contained fusion reaction t

If they can get a continuous fusion reaction going converting the heat energy from that to electricity won't be a problem. Getting a contained fusion reaction that gives out more energy than input is the problem how to convert that into electricity is not going to be a problem.

jacquesm 4y ago
> If they can get a continuous fusion reaction going converting the heat energy from that to electricity won't be a problem. Even accepting the qualification that's not just a mere matter of engineering, capturing that heat from a source that hot is not without trouble. A bit like how there is plenty of energy in a single lightning strike and yet we can't easily catch it even though in principle 'just build a large enough capacitor and connect it to a lightning rod' is a workable recipe. > Getting a contained fusion reaction that gives out more energy than input is the problem Not in the least because the container itself is a very hard problem to solve. > how to convert that into electricity is not going to be a problem. It is also a problem, albeit a lesser one. The better way to look at all of these fusion projects is a way to do an end run around arms control limitations with as a very unlikely by-product the possible future generation of energy. But I would not hold my breath for that. Meanwhile, I'm all for capturing more of the energy output by that other fusion reactor that we all have access to, and learning how to store it over longer periods. Preferably to start with a couple of days with something that doesn't degrade (think very high density super capacitor rather than a battery), but I'll take advanced battery technology if it can be done cheap enough per storage cycle. We're getting there.
- dd36 4y ago
  There’s not plenty of energy in a lightning strike. https://engineering.mit.edu/engage/ask-an-engineer/is-there-a-way-to-harness-electricity-from-lightning/ https://engineering.mit.edu/engage/ask-an-engineer/is-there-...
  - HPsquared 4y ago
    Funnily enough it's about the same order of magnitude as the fusion event discussed in this TFA: about 1 MJ. Energy from one hohlraum ≈ energy from two lightning strikes
moloch-hai 4y ago
It doesn't make heat. It makes fast neutrons. Turning them into usable heat is a project of its own. Turning dumb heat into electric power is expensive. Nothing that depends on doing that can ever compete with wind and solar, anymore. Tritium doesn't grow on trees. Making it by blasting those hot neutrons into a thousand tons of FLiBe is easy enough. Getting your few grams a day, at PPB concentration, out of that thousand tons of stuff is... nobody has any idea how. But you need to, to have fuel for tomorrow. No, there won't be any of that. It would be fantastically more expensive than fission. Fission is not competitive, and gets less so by the day. Fusion is nothing but a money pit (with the just barely-possible exception of D-3He).
- zbobet2012 4y ago
  You've been all over this thread with some aggressive takes that are pretty seriously not supported. > Turning dumb heat into electric power is expensive. Nothing that depends on doing that can ever compete with wind and solar, anymore. This isn't even strictly true today when focusing on current "dumb heat sources": https://en.wikipedia.org/wiki/Cost_of_electricity_by_source#IEA_&_OECD_NEA_(2020) https://en.wikipedia.org/wiki/Cost_of_electricity_by_source#... "cost of extension of operations of existing nuclear power plants (LTO, long-term operations) has the lowest LCOE of low-carbon energy sources; " I'm going to go with the OECD and NEA on this one. > Tritium doesn't grow on trees. https://en.wikipedia.org/wiki/Breeding_blanket https://en.wikipedia.org/wiki/Breeding_blanket Saying that there are unknown engineering challenges is kind of a "duh", otherwise we wouldn't be researching we would be implementing. As you also mentioned there are other alternatives which we could consider than tritium. > Fission is not competitive, and gets less so by the day. https://www.sciencedirect.com/science/article/abs/pii/S0306261922006328 https://www.sciencedirect.com/science/article/abs/pii/S03062... yeah that's not true > Fusion is nothing but a money pit (with the just barely-possible exception of D-3He). We genuinely don't know if fusion is a money pit or not, because we don't have any idea how much a successful form will cost. Tritium blankets may be easy or not. Maybe helion's D-3HE will have a breakthrough. Maybe it's ICF. I've not seen suggestions by anyone that wind and solar build-outs stop, or get diminished. Indeed at this point because the cost are low, industry will continue to invest in them regardless. However, we will need a lot more energy production than folks think. We need to decarbonize the atmosphere. And that's going to require a lot of power. All that aside, solar and wind are not getting you to mars in a timely fashion. We have reasons to research fusion that escape large commercial power generation.

jacquesm 4y ago

> If they can get a continuous fusion reaction going converting the heat energy from that to electricity won't be a problem. Even accepting the qualification that's not just a mere matter of engineering, capturing that heat from a source that hot is not without trouble. A bit like how there is plenty of energy in a single lightning strike and yet we can't easily catch it even though in principle 'just build a large enough capacitor and connect it to a lightning rod' is a workable recipe. > Getting a contained fusion reaction that gives out more energy than input is the problem Not in the least because the container itself is a very hard problem to solve. > how to convert that into electricity is not going to be a problem. It is also a problem, albeit a lesser one. The better way to look at all of these fusion projects is a way to do an end run around arms control limitations with as a very unlikely by-product the possible future generation of energy. But I would not hold my breath for that. Meanwhile, I'm all for capturing more of the energy output by that other fusion reactor that we all have access to, and learning how to store it over longer periods. Preferably to start with a couple of days with something that doesn't degrade (think very high density super capacitor rather than a battery), but I'll take advanced battery technology if it can be done cheap enough per storage cycle. We're getting there.

dd36 4y ago
There’s not plenty of energy in a lightning strike. https://engineering.mit.edu/engage/ask-an-engineer/is-there-a-way-to-harness-electricity-from-lightning/ https://engineering.mit.edu/engage/ask-an-engineer/is-there-...
- HPsquared 4y ago
  Funnily enough it's about the same order of magnitude as the fusion event discussed in this TFA: about 1 MJ. Energy from one hohlraum ≈ energy from two lightning strikes

moloch-hai 4y ago

It doesn't make heat. It makes fast neutrons. Turning them into usable heat is a project of its own. Turning dumb heat into electric power is expensive. Nothing that depends on doing that can ever compete with wind and solar, anymore. Tritium doesn't grow on trees. Making it by blasting those hot neutrons into a thousand tons of FLiBe is easy enough. Getting your few grams a day, at PPB concentration, out of that thousand tons of stuff is... nobody has any idea how. But you need to, to have fuel for tomorrow. No, there won't be any of that. It would be fantastically more expensive than fission. Fission is not competitive, and gets less so by the day. Fusion is nothing but a money pit (with the just barely-possible exception of D-3He).

zbobet2012 4y ago
You've been all over this thread with some aggressive takes that are pretty seriously not supported. > Turning dumb heat into electric power is expensive. Nothing that depends on doing that can ever compete with wind and solar, anymore. This isn't even strictly true today when focusing on current "dumb heat sources": https://en.wikipedia.org/wiki/Cost_of_electricity_by_source#IEA_&_OECD_NEA_(2020) https://en.wikipedia.org/wiki/Cost_of_electricity_by_source#... "cost of extension of operations of existing nuclear power plants (LTO, long-term operations) has the lowest LCOE of low-carbon energy sources; " I'm going to go with the OECD and NEA on this one. > Tritium doesn't grow on trees. https://en.wikipedia.org/wiki/Breeding_blanket https://en.wikipedia.org/wiki/Breeding_blanket Saying that there are unknown engineering challenges is kind of a "duh", otherwise we wouldn't be researching we would be implementing. As you also mentioned there are other alternatives which we could consider than tritium. > Fission is not competitive, and gets less so by the day. https://www.sciencedirect.com/science/article/abs/pii/S0306261922006328 https://www.sciencedirect.com/science/article/abs/pii/S03062... yeah that's not true > Fusion is nothing but a money pit (with the just barely-possible exception of D-3He). We genuinely don't know if fusion is a money pit or not, because we don't have any idea how much a successful form will cost. Tritium blankets may be easy or not. Maybe helion's D-3HE will have a breakthrough. Maybe it's ICF. I've not seen suggestions by anyone that wind and solar build-outs stop, or get diminished. Indeed at this point because the cost are low, industry will continue to invest in them regardless. However, we will need a lot more energy production than folks think. We need to decarbonize the atmosphere. And that's going to require a lot of power. All that aside, solar and wind are not getting you to mars in a timely fashion. We have reasons to research fusion that escape large commercial power generation.