Tuesday saw the official agreement between a consortium of countries to construct a fully functional fusion reactor, at a cost of 12.8 billion dollars, or thereabouts. The project is called the International Thermonuclear Experimental Reactor, ITER. It is indeed a huge undertaking, and we could end up with nothing to show for it, but on the other hand it would be a miniscule price to pay if we were to get the scheme off the ground. The promise of an abundant source of energy that is (supposedly) less polluting and safer to run than fission and does not add to our upcoming woes caused by climate change is too tantalizing not to pursue.
In case you’re wondering, the image to the right (click for larger) is a schematic representation of the 500MW reactor. It is of the classic “Tokamak” type, in which there is a torus (doughnut) shaped region where the plasma will be magnetically contained, at a temperature of 100 million K. To learn more about fusion, you can go to the article from the UKAEA here, and the article on ITER here at their website. From the latter, you can learn about the specific scientific objectives of ITER:
- Achieve inductive plasma burn with power amplification, Q (ratio of fusion power to auxiliary heating power), of at least 10, under stationary conditions on the timescales of plasma processes;
- Aim at demonstrating steady-state operation with Q > 5;
- Do not preclude the possibility of controlled ignition.
- Integrate the technologies essential for a fusion reactor (e.g. superconducting magnets, remote maintenance);
- Test components for a future reactor (e.g. divertor and torus vacuum pumps);
- Test tritium breeding module concepts for DEMO.
From there, they hope to go on to the next stage: commercial designs… 40 or 45 years from now. See the ITER page on the timelines.)
Of course, we must be careful. Are they really as relatively safe and clean as is claimed, for example? Furthermore, please beware: No matter how promising it might seem, or turn out to seem later on, we must guard against the temptation to see fusion as the simple high-technology fix that is going to solve, in one fell swoop, all the environmental woes that are probably around the corner. Sometimes we come to a point where we must make the choice to look at a deeper solution to some major problem in our society, but we jump at the flashy technological solution. It might be that there is no flashy solution in this case. So we should certainly not risk things by waiting for it to turn up just in case. In fact, looking at the projections for how long the project will take to get us to commercial reactors – 45 years – it is not at all clear that even if fusion were to work, we would get it to work in time. If we continue pouring carbon dioxide into our environment at the rate we are now, (never mind the increased rate which is more likely to occur) by time a functional fusion reactor design is rolled out and built commercially in enough quantities… it will be all way way too late.
Others (Greenpeace for example) argue that the money being spent on the ITER should be better spent on research on alternative fuels, etc, for the reasons I said above and others. I am not sure that it should be an either-or situation. We should be trying a cocktail of efforts, as no simgle solution is going to be enough. This diversification of effort is certainly possible if we stop spending billions on serving up death and destruction in the Middle East, for example. Pulling money away from ITER will not mean that it will be spent on hydrogen fuel cells, or wind or solar power. It does not work that way.