Thanks, Chris, for this great article. I worked in or near fusion for 40 years, both magnetic and inertial, but mostly the latter. Your article is among the best summaries I have seen.
At least there is many useful research and developments around it. Doubt anyone believe it possible, not trying when we have a global economy that can is worse. Just keep Elon Musk away from it, he'll bankrupt the world. Have to go back to the industrial revolution and early electricity and the like to find the same level of wild dreams and fantasies the practical problems complexity and scarcity of materials is dumbfounding. This will not turn the economic technology pyramid upside down.
You forgot one important property. Fusion is not self-sustaining. You must feed most of the electricity that you produce back into the reactor. Suppose super optimistically you can get a fusion gain of 20 which results in a net power out of 5%, and your thermal efficiency is 50%. 95% of your power goes back to the reactor. You get at most half of that back after reconversion to electricity. You need a turbine and a generator that is 10 times larger than the net power out. And you need a heat exchanger that is large enough to feed that TG.
Even if they can solve all the horribly daunting engineering problems, fusion will never be competitive with fission on an even playing field.
Show me at least a conceptual design of a power plant costing less than a trillion, and I will take fusion seriously. "Break Even" in fusion is still a factor of 100 short of more electricity out than in. Take the billions going now to the fusion pipe dream, and put it to finding a breakthrough in something more practical, like extracting uranium from seawater, or maybe drilling for geothermal energy.
"Fusion has taken so long because the reaction occurs under conditions that destroy the machine producing it. Gas turbines waited for alloys, cooling passages and manufacturing precision capable of allowing turbine blades to operate in gas hotter than the metal’s melting point."
Great, highly useful analogy. This one would appear to be far more difficult, and costly, from a material science standpoint.
Super article. Another great example of your ability to thread the needle writing with clarity for the layperson yet with enough technical detail for nerds like us. A rare skill we admire that never ceases to amaze us.
One of the most unusual development in the small world of fusion is probably the announced merger between TAE and Trump Media before the end of the year.
The realist and optimistic presentations of NIF are each flawed, but perhaps the realist one more so. The reactions are exponential - an 8% increase in laser power produced a 230% increase in fusion power despite a lower quality target.
The NIF only does several fusion power shots a year as they are primarily about the weapons stockpile and its physics. New lasers are large multiples more efficient than NIF, which in combination with the exponential potential of upping the power creates the fairly near term possibility of a net power plant.
It may be 20 years to a commercial plant though, and even then its commercial edge depends on regulations multiplying the cost of fission. Fusion execs have referred to the field as a "regulatory arbitrage". This may remain a solid basis for commercial competition in substantial markets.
Helion seems to uniquely provide a reactor concept with a physics advantage on fission and is the most interesting in terms of potential.
Good piece. The key point is that “fusion breakthrough” and “fusion power plant” are still very different things. NIF proved something important. It did not prove cheap, reliable electricity. There are still huge hurdles around tritium breeding, materials, maintenance, repetition rates and whole-plant energy balance. So yes: fund fusion. Cheer the breakthroughs. But maybe don’t demolish perfectly good fission plants while waiting for the Sun-in-a-box model to ship. Looking at YOU, Germany...
NIF is not an energy project all though it is often conflated with it. That is a fusion weapons simulation platform. That's why it is funded so much.
We could build PACER fusion plants right now if we wanted. If you blasted out a giant cavern in granite or basalt and filled it with thorium molten salts. Then you had a fully automated factory above it that made 1kt fusion bomb cores. Which would be dropped one per hour into the molten salt and detonated. And U-233 extracted from the salt to supply the fission triggers needed. A power output of about 1GWth. More expensive than a molten salt reactor and politically untenable, most likely.
ITER is a giant bait-and-switch scam and a $65B boondoggle. The purpose of ITER was to delay fusion as long as possible and it worked admirably. The triple product, best measure of fusion viability, had increased steadily by a factor of 100,000 from 1965 to 2000. Between 1970 & 1997 fusion power produced in experimental Tokamaks grew a trillionX. Steady progress. until ITER started, then progress stagnated.
International cooperation giant effort to make a giganormous Tokamak in one country, instead of spirited competition between nations. The pinnacle of bureaucratic boondoggles. Design began in 1992, approval in 2006, construction started in 2013. They spent 5yrs arguing about where to build it. $65B cost estimate now. Might finally start making plasma in 2034, and become operational in 2039. And it was already obsolete from the first shovelful of dirt dug to build it. And now has major problems due to the international components don't fit together properly.
ITER is a $65B boondoggle, whose purpose is to DELAY practical fusion, not achieve it, by misdirecting scant capital & skilled personnel from realistic fusion development. Examples: LPP Focus Fusion, General Fusion, Commercial Fusion Systems, Polywell fusion, Helion energy, Zap energy, Tokamak Energy, First Light Fusion, ARC fusion, TAE technologies, Lockheed Compact fusion, Tri-Alpha Energy.
ITER Is a Suicidal Plan That Would Discredit Nuclear Fusion, Scientist Says, Again:
The smaller privately funded fusion companies are where the fusion hopes lie now. And to get a ROI in a reasonably short time-frame they are starting to focus on fusion applications rather than fusion power plants. A fusion design that may not be practical for commercial energy production may be very effective for Space propulsion. An excellent application is for producing isotopes, especially plutonium for fission reactor MOX fuel and Pu-238 for space applications, maybe U-233 for reactor fuel and even gold, produced from mercury, ~2 tonnes/GWth-yr is possible. And tritium and He-3. And Li-6 or Li-7 isotopes have high value. And recycling of spent nuclear fuel. Or fission-fusion hybrids already in development.
Agree to a degree WRT ITER. While much has been learned from the exercise, even if 10x Q is attained (estimated to be required for commercial power plant), it would be at least another 60B for the next step, the DEMO power generation facility. While I agree this is sucking a lot of the air out of more promising avenues, I can't believe it's deliberate, rather simply a demonstration of stubborn motivation to plough on with the initial plan. and a lack of political will to admit defeat.
Thank you, I learned a lot from this. The path to commercialization is clearly long, but I think it is still worth tackling these challenges.
This seems especially true for a country like Japan, which already has strong underlying technologies but depends heavily on imported energy. The process of working on these problems may itself turn out to be an important investment in the future.
I think it's worth remembering how many different problems have to be solved simultaneously for fusion: plasma confinement, materials that can withstand neutron bombardment, tritium breeding, heat extraction, and ultimately the economics of running an entire power plant. None of these problems is trivial, and we still don't know whether we'll be able to make fusion competitive on the grid.
But even in the worst-case scenario, where grid-scale fusion doesn't work out the way we hope, the technology we're developing doesn't simply disappear. We're already seeing applications of fusion-related technology in areas like medical isotope production, while also exploring its potential for space propulsion. So perhaps the question isn't only whether fusion will power our grids - it's also what else we can build along the way.
Also, this is an amazing piece for anyone who wants to understand fusion from the physics, policy, and economic perspectives without getting buried in jargon. Really enjoyed this one!
In Janesville, WI Shine is building a facility that use DT neutron generators using a compact particle accelerator to fuse deuterium and tritium. The neutrons are used to irradiate a uranyl sulfate target solution in a subcritical assembly to cause fission. They then extract Mo-99 (and other medical radioisotopes) from the solution for medical uses.
One interesting aspect of this operation is that since the fusion created neutrons are causing fissions in a subcritical assembly the NRC considers the fission products to be Low Level Waste (LLW). Sixty miles southwest of the Shine facility at the Byron Nuclear Plant the uranium fission products are considered spent nuclear fuel but at Shine those same fission products are considered LLW.
I worked on laser fusion in the 70's, while we were still trying to get a perfectly spherical implosion of an LiDT pellet. The motivation for fusion was our belief that there was not enough uranium fuel for long-term sustainability. Now that worry is gone, there is no advantage to fusion.
My hope is that our societies come to accept fission power for what it is. Yes there are downsides but they are being managed safely but societal fears results in economic inefficiencies that hinders deployment. It won't happen in my lifetime but hope my dependents get to live in a world in which climate change hasn't wreaked more havoc. Nuclear energy is essential to that future.
The fuel is also a problem. Very little since it is produced out of nuclear waste. Used up quickly because minute compared to uranium. Have enough of a shortage of that and getting shorter all the time. Fusion is a dream at best and a waste of money.... Just doesn't have the infrastructure. This is why has been found in my research....
Thanks, Chris, for this great article. I worked in or near fusion for 40 years, both magnetic and inertial, but mostly the latter. Your article is among the best summaries I have seen.
I don't see fusion ever working, but I hope I'm wrong.
At least there is many useful research and developments around it. Doubt anyone believe it possible, not trying when we have a global economy that can is worse. Just keep Elon Musk away from it, he'll bankrupt the world. Have to go back to the industrial revolution and early electricity and the like to find the same level of wild dreams and fantasies the practical problems complexity and scarcity of materials is dumbfounding. This will not turn the economic technology pyramid upside down.
You forgot one important property. Fusion is not self-sustaining. You must feed most of the electricity that you produce back into the reactor. Suppose super optimistically you can get a fusion gain of 20 which results in a net power out of 5%, and your thermal efficiency is 50%. 95% of your power goes back to the reactor. You get at most half of that back after reconversion to electricity. You need a turbine and a generator that is 10 times larger than the net power out. And you need a heat exchanger that is large enough to feed that TG.
Even if they can solve all the horribly daunting engineering problems, fusion will never be competitive with fission on an even playing field.
https://jackdevanney.substack.com/p/the-trouble-with-fusion
Show me at least a conceptual design of a power plant costing less than a trillion, and I will take fusion seriously. "Break Even" in fusion is still a factor of 100 short of more electricity out than in. Take the billions going now to the fusion pipe dream, and put it to finding a breakthrough in something more practical, like extracting uranium from seawater, or maybe drilling for geothermal energy.
"Fusion has taken so long because the reaction occurs under conditions that destroy the machine producing it. Gas turbines waited for alloys, cooling passages and manufacturing precision capable of allowing turbine blades to operate in gas hotter than the metal’s melting point."
Great, highly useful analogy. This one would appear to be far more difficult, and costly, from a material science standpoint.
Super article. Another great example of your ability to thread the needle writing with clarity for the layperson yet with enough technical detail for nerds like us. A rare skill we admire that never ceases to amaze us.
One of the most unusual development in the small world of fusion is probably the announced merger between TAE and Trump Media before the end of the year.
The realist and optimistic presentations of NIF are each flawed, but perhaps the realist one more so. The reactions are exponential - an 8% increase in laser power produced a 230% increase in fusion power despite a lower quality target.
The NIF only does several fusion power shots a year as they are primarily about the weapons stockpile and its physics. New lasers are large multiples more efficient than NIF, which in combination with the exponential potential of upping the power creates the fairly near term possibility of a net power plant.
It may be 20 years to a commercial plant though, and even then its commercial edge depends on regulations multiplying the cost of fission. Fusion execs have referred to the field as a "regulatory arbitrage". This may remain a solid basis for commercial competition in substantial markets.
Helion seems to uniquely provide a reactor concept with a physics advantage on fission and is the most interesting in terms of potential.
Good piece. The key point is that “fusion breakthrough” and “fusion power plant” are still very different things. NIF proved something important. It did not prove cheap, reliable electricity. There are still huge hurdles around tritium breeding, materials, maintenance, repetition rates and whole-plant energy balance. So yes: fund fusion. Cheer the breakthroughs. But maybe don’t demolish perfectly good fission plants while waiting for the Sun-in-a-box model to ship. Looking at YOU, Germany...
NIF is not an energy project all though it is often conflated with it. That is a fusion weapons simulation platform. That's why it is funded so much.
We could build PACER fusion plants right now if we wanted. If you blasted out a giant cavern in granite or basalt and filled it with thorium molten salts. Then you had a fully automated factory above it that made 1kt fusion bomb cores. Which would be dropped one per hour into the molten salt and detonated. And U-233 extracted from the salt to supply the fission triggers needed. A power output of about 1GWth. More expensive than a molten salt reactor and politically untenable, most likely.
ITER is a giant bait-and-switch scam and a $65B boondoggle. The purpose of ITER was to delay fusion as long as possible and it worked admirably. The triple product, best measure of fusion viability, had increased steadily by a factor of 100,000 from 1965 to 2000. Between 1970 & 1997 fusion power produced in experimental Tokamaks grew a trillionX. Steady progress. until ITER started, then progress stagnated.
International cooperation giant effort to make a giganormous Tokamak in one country, instead of spirited competition between nations. The pinnacle of bureaucratic boondoggles. Design began in 1992, approval in 2006, construction started in 2013. They spent 5yrs arguing about where to build it. $65B cost estimate now. Might finally start making plasma in 2034, and become operational in 2039. And it was already obsolete from the first shovelful of dirt dug to build it. And now has major problems due to the international components don't fit together properly.
ITER is a $65B boondoggle, whose purpose is to DELAY practical fusion, not achieve it, by misdirecting scant capital & skilled personnel from realistic fusion development. Examples: LPP Focus Fusion, General Fusion, Commercial Fusion Systems, Polywell fusion, Helion energy, Zap energy, Tokamak Energy, First Light Fusion, ARC fusion, TAE technologies, Lockheed Compact fusion, Tri-Alpha Energy.
ITER Is a Suicidal Plan That Would Discredit Nuclear Fusion, Scientist Says, Again:
news.newenergytimes.net/2020/12/05/iter-is-a-suicidal-plan-that-would-discredit-nuclear-fusion/
The smaller privately funded fusion companies are where the fusion hopes lie now. And to get a ROI in a reasonably short time-frame they are starting to focus on fusion applications rather than fusion power plants. A fusion design that may not be practical for commercial energy production may be very effective for Space propulsion. An excellent application is for producing isotopes, especially plutonium for fission reactor MOX fuel and Pu-238 for space applications, maybe U-233 for reactor fuel and even gold, produced from mercury, ~2 tonnes/GWth-yr is possible. And tritium and He-3. And Li-6 or Li-7 isotopes have high value. And recycling of spent nuclear fuel. Or fission-fusion hybrids already in development.
PACER is "politically untenable"
You think?
Agree to a degree WRT ITER. While much has been learned from the exercise, even if 10x Q is attained (estimated to be required for commercial power plant), it would be at least another 60B for the next step, the DEMO power generation facility. While I agree this is sucking a lot of the air out of more promising avenues, I can't believe it's deliberate, rather simply a demonstration of stubborn motivation to plough on with the initial plan. and a lack of political will to admit defeat.
Thank you, I learned a lot from this. The path to commercialization is clearly long, but I think it is still worth tackling these challenges.
This seems especially true for a country like Japan, which already has strong underlying technologies but depends heavily on imported energy. The process of working on these problems may itself turn out to be an important investment in the future.
I think it's worth remembering how many different problems have to be solved simultaneously for fusion: plasma confinement, materials that can withstand neutron bombardment, tritium breeding, heat extraction, and ultimately the economics of running an entire power plant. None of these problems is trivial, and we still don't know whether we'll be able to make fusion competitive on the grid.
But even in the worst-case scenario, where grid-scale fusion doesn't work out the way we hope, the technology we're developing doesn't simply disappear. We're already seeing applications of fusion-related technology in areas like medical isotope production, while also exploring its potential for space propulsion. So perhaps the question isn't only whether fusion will power our grids - it's also what else we can build along the way.
Also, this is an amazing piece for anyone who wants to understand fusion from the physics, policy, and economic perspectives without getting buried in jargon. Really enjoyed this one!
In Janesville, WI Shine is building a facility that use DT neutron generators using a compact particle accelerator to fuse deuterium and tritium. The neutrons are used to irradiate a uranyl sulfate target solution in a subcritical assembly to cause fission. They then extract Mo-99 (and other medical radioisotopes) from the solution for medical uses.
One interesting aspect of this operation is that since the fusion created neutrons are causing fissions in a subcritical assembly the NRC considers the fission products to be Low Level Waste (LLW). Sixty miles southwest of the Shine facility at the Byron Nuclear Plant the uranium fission products are considered spent nuclear fuel but at Shine those same fission products are considered LLW.
Isn't the difference that the bombardment doesn't result in long-lived actinides?
I worked on laser fusion in the 70's, while we were still trying to get a perfectly spherical implosion of an LiDT pellet. The motivation for fusion was our belief that there was not enough uranium fuel for long-term sustainability. Now that worry is gone, there is no advantage to fusion.
"but the waste"
My hope is that our societies come to accept fission power for what it is. Yes there are downsides but they are being managed safely but societal fears results in economic inefficiencies that hinders deployment. It won't happen in my lifetime but hope my dependents get to live in a world in which climate change hasn't wreaked more havoc. Nuclear energy is essential to that future.
The fuel is also a problem. Very little since it is produced out of nuclear waste. Used up quickly because minute compared to uranium. Have enough of a shortage of that and getting shorter all the time. Fusion is a dream at best and a waste of money.... Just doesn't have the infrastructure. This is why has been found in my research....