Chapter 9: Are We Ready for a Fusion Moonshot?
This is Chapter 9 from free climate book?A Plan to Save the Planet.
There are two types of nuclear power: fission and fusion. Traditional nuclear power plants generate electricity with uranium via fission. However, this is not popular due to meltdown risk, nuclear waste, nuclear bomb proliferation risk, and cost. Fusion, on the other hand, does not have these issues; however, it is still in development. Typical fusion systems maintain a hot plasma in a donut-shaped reactor called a Tokamak, as illustrated above.?
The First Moonshot
In 1961, President Kennedy stated he wanted a man on the moon by the end of the decade. In response, a program was set up and funded. In theory, a government leader could do the same with nuclear fusion power. For example, they could state that commercial fusion must be operational within 10 years. This might seem unrealistic. However, notice how many “gadgets” the U.S. designed and manufactured between 1939 and 1945.
Commercial Fusion Moonshot
“Commercial fusion” refers to generating electricity at a cost comparable to electricity made with natural gas or coal. This requires the fusion reactor to run for long durations, without failure, and at a low cost.
A “moonshot” refers to a large R&D initiative that is implemented over a relatively short period of time. One might define “fusion moonshot” as:
Achieve commercial fusion within 10 years.
Fusion Milestones
There are three fusion milestones that have not yet been met:
Heat is Probably Not the Problem
Reports in national media suggest current fusion reactors do not produce sufficient heat. This is true. However, heat increases when one increases the strength of the magnets, and stronger magnets were recently developed at MIT. These will be installed into a test reactor soon, and MIT hopes to demonstrate sufficient heat in 2025. In other words, heat is probably not the problem.
So what is the problem? Below are several.
Challenge #1: Reactor Build Time
Fusion test reactors typically take many years to build, and this is probably the greatest obstacle to commercial fusion. To move rapidly, one might need hundreds, or even thousands of engineers in places like China who can build and test quickly.
What does Elon Musk do after one of his rockets fails in spectacular fashion? He repeats. And after dozens of cycles, a working system emerges. To get commercial fusion working quickly, a similar approach might be needed.
Challenge #2: Component Longevity
To produce electricity at a low cost, a commercial fusion reactor would need to run for long durations without failure. To ensure longevity, engineers could run individual components in test fixtures at maximum power, or more, to see how and when they break, and then improve as needed. This might sound easy; however, doing this with many components takes time and requires many engineers. And if a delicate component, such as a magnet, fails prematurely on a regular basis, a remedy might not be quick or easy.
Challenge #3: Disposable Plasma Confinement Chamber
The heat from a fusion reactor core needs to be moved outward, to create steam, to press on turbine fan blades, to produce electricity. The easiest way to do this is to pump fluids, such as molten lead or molten salt, toward the hot plasma, and then outward.
Neutron radiation from hot plasma weakens surrounding metal for about one meter of penetration depth. Consequently, the plasma confinement chamber would need to be replaced approximately once a year. This chamber is labeled “blanket” in the above illustration. In other words, one might need to fabricate 50 of these chambers over a 50-year period. And fabricating these at low cost would probably require automation and molded processes. For example, an industrial robot might weld together molded metal panels affixed to a jig on a rotating table.
It is not difficult for a team of engineers, or even one engineer, to design the mechanics of how a fusion reactor fits together. Also, multiple teams could create multiple designs that are later selected or merged after being reviewed. However, it is not clear how to identify the best design. And after committing to one design, it might take many years to build and test.
To help verify designs, one could build prototypes quickly that are 1 to 10m3 in size. These might not include magnets, and might not maintain the plasma. However, they could verify assembly of molded panels via industrial robots, verify pumping of fluids at high pressure, verify moving heat, and verify replacing internal components via industrial robots.
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To Plan or Not To Plan?
There are two ways to manage a large development initiative. The traditional method is to develop a plan, get it funded, and implement. Alternatively, one can set goals, assemble a top team, give them authority, provide funding, and get out of their way. The traditional method works well if one knows what needs to be done. Unfortunately, commercial fusion is not well understood.
Achieve Commercial Fusion as Soon as Possible
ITER is a $25B fusion reactor development program based in France. Their reactor was designed 20 years ago and is currently obsolete due to advances over the last two decades. If ITER had been driven by a goal instead of a plan, it would probably be further along. An example goal might be, “achieve commercial fusion as soon as possible given $1B/yr.”
How Might a Foundation Accelerate Fusion Development?
If a philanthropic foundation wanted to accelerate the development of fusion power with $100M, for example, how might it proceed? Below is one possible approach.
How Is This Different?
After the typical fusion R&D initiative commits to one design and begins construction, money and talent focus on building the test reactor instead of more design. Also, most fusion research programs focus on the first two milestones (i.e. more heat, remove heat) as opposed to commercial fusion (i.e. low cost, reliable, serviceable, automated assembly). Therefore, an initiative that focuses on design-only, open source, cost reduction, component longevity, and automated fabrication/maintenance would be different from existing fusion development initiatives.
When to Profit?
If the above initiative ultimately led to a commercial fusion reactor, its design could potentially be licensed for manufacture. Licensing revenue could then be fed back to the organizations that designed it. The world's fusion organizations know this. Therefore, they might be inclined to convert an open-source initiative to proprietary. For example, top people might stop contributing to open source when it is 90% complete, and do the last 10% as proprietary. In other words, a philanthropic foundation might get this started open source. However, ultimately, the financial interests of governments, investors, companies, and fusion research institutions might cause them to lose interest in open source when close to complete (which would be okay).
Getting Started with $100M
Why would this initiative not be funded originally by commercial investors? That is already happening; however, those efforts are not expected to produce commercial fusion before 2040.
Why would this initiative not be funded originally by government? That is already happening too. However, national interests and emphasis on plan are not expected to produce commercial fusion any time soon.
To accelerate fusion development, one might initially need a sponsor who is not looking for a return on investment, requires transparency, is willing to give power to top people, and encourages participation across national boundaries.
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This is another article on fusion: What Might a $10B Fusion R&D Initiative Look Like? https://www.eetimes.com/what-might-a-10b-fusion-rd-initiative-look-like/