3 ms·

> There was also a breakthrough in late 2021, when researchers at the Joint European Torus (JET) facility in Oxford managed to release a record-breaking 59 mega

> There was also a breakthrough in late 2021, when researchers at the Joint European Torus (JET) facility in Oxford managed to release a record-breaking 59 megajoules of fusion 59 megajoules in useful units is 16kWh, less than 2 days use of my house. That's the biggest fusion reaction ever.

chris_va 4y ago
https://en.wikipedia.org/wiki/Tsar_Bomba https://en.wikipedia.org/wiki/Tsar_Bomba ... was slightly larger than that. Anyway, 59MJ isn't terrible if you can run it at 60Hz. Of course, I agree that the reality is a bit far away.
toveja 4y ago
59 megajoules of sustained energy ^over the course of a few seconds^. Ideally this energy output would be sustained for days within ITER. JET is not designed to do this, as it has a copper magnet system, which means if you try to sustain such a plasma (confined with around 5 T magnet and around 2 MA plasma current) for longer than a few seconds, you would melt the magnet. Edit: ITER would operate at 5-10 T, and around 15-20 MA plasma current.
- tsimionescu 4y ago
  Note that these are 59MJ of energy released by the fusion reaction. No attempt was made to actually catch them. And even if they had been captured, they would not have been able to power the magnets + cooling systems used to confine the plasma. We are very very far away from actually producing even 1W of usable fusion power.
  - toveja 4y ago
    You are correct that at JET there is no tech installed to absorb the neutrons, nor will there ever be in JET, since (as pointed out above) it is a _research_ device. Current fusion devices are not nor were they ever designed to generate electricity for a grid. This is why we build ITER, and DEMO thereafter. Generating 'usable fusion power' is limited to building reactor scale experiments, which to date, has not been done (ITER will be the first).
    - tsimionescu 4y ago
      ITER is also not planning to capture the neutrons. It is only planned to produce more thermal energy than the total amount of electrical energy put in. DEMO will be plants built independently by several nations following the research from a successful ITER. They will be the first time that any attempt is made to actually convert the fusion products into electricity. There are currently no concrete plans for any DEMO plant - those are contingent upon ITER's success. If everything goes to plan, the first model DEMO plant would begin operation in 2051. So, as I said, we are a long way away from producing even 1W of usable electrical power from fusion.
DeIonizedPlasma 4y ago
59MJ over the short period of 7s, equivalent to 8.5 MW (https://www.iter.org/newsline/-/3722 https://www.iter.org/newsline/-/3722). A research reactor (not built to be a power plant) that is still capable of powering over 20,000 households while running isn't really as underwhelming as you seem to imply it is.
tiborsaas 4y ago
The first human flight lasted 12 seconds, don't judge achievements by the numbers.

chris_va 4y ago

https://en.wikipedia.org/wiki/Tsar_Bomba https://en.wikipedia.org/wiki/Tsar_Bomba ... was slightly larger than that. Anyway, 59MJ isn't terrible if you can run it at 60Hz. Of course, I agree that the reality is a bit far away.

toveja 4y ago

59 megajoules of sustained energy ^over the course of a few seconds^. Ideally this energy output would be sustained for days within ITER. JET is not designed to do this, as it has a copper magnet system, which means if you try to sustain such a plasma (confined with around 5 T magnet and around 2 MA plasma current) for longer than a few seconds, you would melt the magnet. Edit: ITER would operate at 5-10 T, and around 15-20 MA plasma current.

tsimionescu 4y ago
Note that these are 59MJ of energy released by the fusion reaction. No attempt was made to actually catch them. And even if they had been captured, they would not have been able to power the magnets + cooling systems used to confine the plasma. We are very very far away from actually producing even 1W of usable fusion power.
- toveja 4y ago
  You are correct that at JET there is no tech installed to absorb the neutrons, nor will there ever be in JET, since (as pointed out above) it is a _research_ device. Current fusion devices are not nor were they ever designed to generate electricity for a grid. This is why we build ITER, and DEMO thereafter. Generating 'usable fusion power' is limited to building reactor scale experiments, which to date, has not been done (ITER will be the first).
  - tsimionescu 4y ago
    ITER is also not planning to capture the neutrons. It is only planned to produce more thermal energy than the total amount of electrical energy put in. DEMO will be plants built independently by several nations following the research from a successful ITER. They will be the first time that any attempt is made to actually convert the fusion products into electricity. There are currently no concrete plans for any DEMO plant - those are contingent upon ITER's success. If everything goes to plan, the first model DEMO plant would begin operation in 2051. So, as I said, we are a long way away from producing even 1W of usable electrical power from fusion.

DeIonizedPlasma 4y ago

59MJ over the short period of 7s, equivalent to 8.5 MW (https://www.iter.org/newsline/-/3722 https://www.iter.org/newsline/-/3722). A research reactor (not built to be a power plant) that is still capable of powering over 20,000 households while running isn't really as underwhelming as you seem to imply it is.

tiborsaas 4y ago

The first human flight lasted 12 seconds, don't judge achievements by the numbers.