Nuclear Ships and Missile Defense
Nuclear cargo ships will be slow and missile defense comes of age.
Same Blog, New Substack
All the longer posts I write will stay on my blog. This newsletter will go out once every week or two with a few blurbs and links to any new posts.
Nuclear Cargo Ships
I’ve learned that trains and nuclear power plants have very militant supporters. Some folks get angry if you suggest ships might be anything but nuclear-powered. My latest post is about battery-electric ships, and mentioning the “B” word adds insult to injury for many die-hard nuclear fans.
I think pro-nuclear people should love batteries instead. Think about the startup TerraPower. They are oversizing their electricity generation system and adding molten salt thermal storage to arbitrage electricity prices. Nuclear power plants are already challenging enough to license and build without these gadgets. The cost of stationary storage batteries has plummeted since the company started working on its reactor. Instead of those complicated systems, they could put a bank of batteries down the road and run their nuclear power plant as god intended - steady state at full power!
Batteries also help nuclear ships. Battery chemistries like LFP and marine diesel engines have expensive energy but very cheap power. They cost <$500/kW but $100/MWh. Nuclear reactors are the opposite - they have inexpensive energy but pricey power. A small modular reactor for a ship will cost $5000-$10,000/kW, but the marginal energy cost might be $20/MWh. Battery-electric ships will push new ship designs that are much more efficient to increase range. Containerized nuclear reactors could be drop-in solutions for these ships, replacing battery containers. That extra efficiency will decrease the power requirement, lowering the cost of switching to nuclear.
Another funny thing is that nuclear cargo ships will likely be very slow (at least to start). Energy usage increases with the square of a ship’s velocity, but power increases with the cube of velocity. A nuclear cargo ship that takes advantage of every efficiency gain and halves its speed will reduce its power plant size by 10x. Ship count won’t need to double because cargo ships spend so much time in ports.
If I was a militant believer in nuclear ships, I’d be cheering on battery-powered ships until I was hoarse. They will pay for all the R+D to improve ship efficiency, build the ships, and create segmented markets for slow cargo and fast cargo. Nuclear is a drop-in replacement for batteries on the slow steaming routes once a nuclear startup can build a half-decent containerized reactor.
Missile Defense
There is still some fog of war, but it appears the American Patriot Missile System has shot down seven of Russia’s tactical ballistic missiles. The consensus suggests that one part of the system took damage (A Patriot battery has almost a dozen modules spread over hundreds of acres) but is still online. The efficiency of these shootdowns has implications beyond Ukraine.
Ballistic missiles are hard to shoot down because they are so fast. And the thinking has been that the most realistic place to intercept them is at a high altitude before they start their downward trajectory. The US Army’s primary ballistic missile defense system, THAAD, works like this. The Patriot batteries in Ukraine downing ballistic missiles at lower altitudes with the older version of PAC-3 interceptors is a bit of an upset.
The implications extend to the Western Pacific because China has been buying hundreds of ballistic missiles to strike at US airbases and Navy carriers. It is the centerpiece of their strategy to limit America’s ability to intervene if they attack their neighbors. The ultimate impact is that China must launch much larger missile salvos at US bases to overwhelm missile defenses. Those are resources it can’t use for a Taiwan invasion. The US Air Force is also hardening its bases and adding dispersal airfields. That will further increase how many missiles China needs to shoot. Air bases are notoriously hard to knock offline, and keeping airbases down may not be a feasible goal for China if active missile defenses are very efficient.
I wrote about a similar theme in a post called “Weapons that Win World Wars.” Fundamentally missile interceptors should have an advantage because they can be much smaller than long-range aggressor missiles if they intercept them at shorter ranges (though they must be maneuverable and located near the target). Maybe we are at the crossover where software, sensors, and actuators are good enough to knock down most incoming missiles. Attackers must rethink their designs and add decoys, stealth, or jamming.