4 ms·

It's questionable. ITER's design comes from the late 1990s and early 2000s. Hight Temperature Superconductors (HTS) have changed the game. HTS tape has only be

by sien 7y ago

It's questionable. ITER's design comes from the late 1990s and early 2000s. Hight Temperature Superconductors (HTS) have changed the game. HTS tape has only been available for about a decade. The cube of magnetic field is proportional to the energy gain in a Tokomak. See this video at at 46 minutes to get the equation, watch more to understand why people are now doing this. https://www.youtube.com/watch?v=L0KuAx1COEk https://www.youtube.com/watch?v=L0KuAx1COEk Tokomak Energy and Commonwealth Fusion Systems among others are looking at smaller reactors that use High Temperature Superconductors. Also have a look at Helion Energy. Also note that the Chinese are starting to put serious money into fusion research. https://www.reuters.com/article/us-china-nuclearpower-fusion/china-targets-nuclear-fusion-power-generation-by-2040-idUSKCN1RO0NB https://www.reuters.com/article/us-china-nuclearpower-fusion...

ikeyany 7y ago
Having worked on that tokomak, I can confirm that the Chinese are not playing around when it comes to funding long-term science initiatives. The US should be doing some serious soul searching about its priorities...where is the collective national vision of tomorrow?
piva00 7y ago
Reading this article one thing that pops in my mind is: we have spent more money collectively to fund the LHC in CERN as we have funded ITER. As much as extremely good science has came out of this experiment it boggles my mind that we have spent less in the search for the next breakthrough in energy generation, something that ALWAYS has catapulted technology and development of humanity. Why?
- pfdietz 7y ago
  The fusion effort is based on a set of assumptions that might have seemed reasonable in the 1950s when the effort got started, but are no longer realistic. Fusion assumes the problem with nuclear power is that uranium is scarce, so the cost of nuclear energy would be dominated by fuel cost. In such a scenario, where reactors themselves are cheap, it makes sense to make a more complex expensive reactor to save on fuel. This was also the motivation for breeder reactors. But this isn't how it worked out. Fuel is a small part of the cost of nuclear fission power. The cost of building and maintaining the power plants, and disposing of them at the ends of their lives, turned out to dominate. In that scenario, making larger, more complex, more expensive reactors just so one can burn deuterium and lithium is totally bass-ackwards. The collapse of the fission breeder program should have been a sign that fusion wasn't going to work either. They were both based on the same incorrect idea of how things were going to go.
  - petschge 7y ago
    Except that fusion reactor have a bunch of advantages over all fission designs, including breeder and molten core Thorium, that you conveniently ignore. The big one is: ramp up time is measured in minutes not days. This is a perfect addition to a grid that gets a large fraction of it's power from (somewhat) variable renewable energy. The next big one is: There is no proliferation risk. No spent fuel that contains isotopes suitable for building fission bombs. And now legitimate reason for uranium enrichment to process your own fresh fuel. In other words there is no reason not to give this technology to North Korea or Iran. The third important one: No radioactive waste that needs to be contained long term. The main "ash" is helium-4 which is not radioactive. The neutron flux will activate parts of the reactor vessel, but the halflifes are generally below a century. General rule of thumb is that things need to be contained 10 halflifes. Humanity has demonstrated successfully that we can build buildings that last 1000 years. This is a big contrast to the waste from fission plants that needs to be contained at least 100000 years, longer than we have had buildings.
    - pfdietz 7y ago
      I ignore these putative advantages because they are of minor importance, compared to the major downside of cost. If fusion is too expensive, all those other things do not matter.

by sien 7y ago

ikeyany 7y ago

Having worked on that tokomak, I can confirm that the Chinese are not playing around when it comes to funding long-term science initiatives. The US should be doing some serious soul searching about its priorities...where is the collective national vision of tomorrow?

piva00 7y ago

Reading this article one thing that pops in my mind is: we have spent more money collectively to fund the LHC in CERN as we have funded ITER. As much as extremely good science has came out of this experiment it boggles my mind that we have spent less in the search for the next breakthrough in energy generation, something that ALWAYS has catapulted technology and development of humanity. Why?

pfdietz 7y ago
The fusion effort is based on a set of assumptions that might have seemed reasonable in the 1950s when the effort got started, but are no longer realistic. Fusion assumes the problem with nuclear power is that uranium is scarce, so the cost of nuclear energy would be dominated by fuel cost. In such a scenario, where reactors themselves are cheap, it makes sense to make a more complex expensive reactor to save on fuel. This was also the motivation for breeder reactors. But this isn't how it worked out. Fuel is a small part of the cost of nuclear fission power. The cost of building and maintaining the power plants, and disposing of them at the ends of their lives, turned out to dominate. In that scenario, making larger, more complex, more expensive reactors just so one can burn deuterium and lithium is totally bass-ackwards. The collapse of the fission breeder program should have been a sign that fusion wasn't going to work either. They were both based on the same incorrect idea of how things were going to go.
- petschge 7y ago
  Except that fusion reactor have a bunch of advantages over all fission designs, including breeder and molten core Thorium, that you conveniently ignore. The big one is: ramp up time is measured in minutes not days. This is a perfect addition to a grid that gets a large fraction of it's power from (somewhat) variable renewable energy. The next big one is: There is no proliferation risk. No spent fuel that contains isotopes suitable for building fission bombs. And now legitimate reason for uranium enrichment to process your own fresh fuel. In other words there is no reason not to give this technology to North Korea or Iran. The third important one: No radioactive waste that needs to be contained long term. The main "ash" is helium-4 which is not radioactive. The neutron flux will activate parts of the reactor vessel, but the halflifes are generally below a century. General rule of thumb is that things need to be contained 10 halflifes. Humanity has demonstrated successfully that we can build buildings that last 1000 years. This is a big contrast to the waste from fission plants that needs to be contained at least 100000 years, longer than we have had buildings.
  - pfdietz 7y ago
    I ignore these putative advantages because they are of minor importance, compared to the major downside of cost. If fusion is too expensive, all those other things do not matter.