Comment by bsder
7 years ago
> The cause is that fusion turned out to be less promising than had been thought
So did a whole lot of chemical rocketry. Instead of whining about it--we spent a lot of money on engineering, we made the Saturn V, and we went to the moon anyway.
The issue is that fusion only has one end point--providing energy. Researching chemical rocketry made better weapons--so we funded the snot out of it. The DOE spent billions on the Unconventional Gas Research Programs and lined a lot of pockets.
Funding isn't guaranteed to make progress, but lack of funding practically guarantees lack of progress.
Not a good analogy. Chemical rockets are the only real way to get to space. So if you make them better, even incrementally, you have a win. It also helped that launchers were very far away from fundamental economic limits on their performance. Expendable launchers, unlike power plants, are expended.
But fusion is competing against a plethora of other approaches to production of energy that actually work, and are being used, and are arguably superior.
Fusion also uses components that are mature due to their use in these other approaches. DT fusion, which Lidsky is addressing, will produce its energy as heat. This heat has to be turned into power using turbines and generators, a mature technology. And it's a mature technology that's a major part of the cost of coal and nuclear power plants, and is a big reason why those power plants are no longer competitive.
(This echoes an argument from the mid 20th century, when it was pointed out that fission power would, at best, be only slightly less expensive than power from coal, due to all the common elements the power plants shared. And it turned out nuclear fission was more expensive than that, as one could not do the nuclear parts too cheaply. DT fusion reactors promise to be much larger and more complex than fission reactors, for the fundamental reasons Lidsky and others gave, so one can reasonably expect their economics to fail even more.)
(This is also why the focus on thorium and SMRs to try to keep fission alive is probably hopeless.)
("Those who cannot remember the past are condemned to repeat it")
The complaint about funding is a red herring. It has the presumption that if funding had been available, fusion had a real chance of succeeding. But as Lidsky points out, it didn't have a real chance of succeeding. Even if the program had produced a reactor, no one would have wanted it.
> This heat has to be turned into power using turbines and generators, a mature technology. And it's a mature technology that's a major part of the cost of coal and nuclear power plants, and is a big reason why those power plants are no longer competitive.
Erm, natural gas uses turbines and generators and nobody seems to be whining about that. It isn't the turbine driving the cost in coal (nuclear is a different story).
First, we still can't engineer a superconductor. We have barely doubled magnetic field strength since 1970ish. And the big advance of superconductivity in graphite with slight offsets demonstrates just how little we know. Superconductors would have had a massive improvement in basic science with funding (this was one of the huge losses in not funding the Superconducting Supercollider).
The FFT (fast fourier transform) was effectively useless in the 1970s and 1980s--until Moore's Law made it not so useless. Similarly, computational dynamics made huge advances since the 1980s--to the point where non-simple toroids are now the standard.
Knowledge advances in a "front". If you throw money at a point (especially a fundamental one), it drags related knowledge forward as well. Look at steel, for example. Steel has been considered "mature and well-understood" (hah!) practically since 1910--but there was so much money being thrown at it that it continuously advanced for almost a century. Once steel moved forward, architecture and construction moved forward. Then we got new applications like cars. Then we got new tooling like heavy presses. Then we could use more exotic materials like titanium. I can go on and on.
Natural gas uses combustion turbines, not steam turbines (except as a bottoming cycle in combined cycle plants, but that produces only 1/3 of the output of the plant).
What combustion turbines allow you to do is avoid heat exchangers, and also operate at a temperature much higher than a steam turbine because no solid material needs to be at the temperature of the working fluid. A simple cycle gas turbine (without regeneration) has no heat exchangers. Heat exchangers are expensive; transfer of heat across a solid/fluid interface is not as fast as we'd like it to be.
This kind of neglects the fact that "rocket science" was just "harder than thought" for american scientists. Stuff started to work when they let German scientists build it.
Which is no surprise. Germany already had dozens amateur (space) rocket clubs way back in 1930, long before people in other countries were even mostly aware of the possibilty of sending rockets way up there.
The US had some catching up to do in the science department, which they accomplished in the end, though rockets loosely based on those initial designs are still in use today.
This is different to today's fusion situation, where we don't know whether there will be any better design at all - because nobody did built something that could be adapted to fit our purpose before us.