Why Nuclear Fusion Won’t Solve the Climate Crisis

If Commonwealth Fusion's approach is viable, we may finally be at the stage where industry sponsored R&D can work. Though in fairness the concept had significant development at MIT, which I assume gets a decent amount of public funding. And there is more expensive work to be done after their first demo reactor SPARC.

Those not familiar with CFS: They are building a tokamak with new high field strength superconducting magnets, allowing them to build a system with similar physics to ITER on a MUCH smaller scale. According to them, stronger magnetic field allows for a proportionally smaller machine, and indeed their new magnet design allows for the strongest field for a tokamak ever.

There are other fusion startups, but I can't keep track of them all. As a layperson, I feel like tokamaks are well understood, JET has confirmed good physics for ITER and SPARC and while the engineering challenges in construction are significant, their smaller design allows for a much faster and cheaper design cycle.

However I agree that fusion will not solve the impending climate crisis, because it will still, even if we had the first working power plant in 10-15 years, take way too long to build out all the plants we need. And the first fusion power plants will not be remotely cost competitive with renewables. It is still a very big and complex machine compared to the relatively commodified solar and storage solution. Remember that in 15 years, batteries will be much cheaper.

What may work well, if we get fusion working, is to build out all the renewables we can now, and then in 30 years when those systems need replacement, build out a mixture of fusion and renewables (which will continue to be very useful and cost competitive).

I would love to see more government investment both in renewables build out and in shoring up fusion research. While we MAY be able to get by with industry funding, that is very much not guaranteed. And the build out itself will need support if we ever get it working.

That's an excellent additional reason why fusion is not a viable solution.