Reading List 12/21/2024
Commercial fusion, Boom’s new funding round, efficient industrial policy, AI fighter jets, and more.
Welcome to the Reading List, a weekly roundup of news and links about buildings, infrastructure, and industrial technology. This week we look at commercial fusion, Boom’s new funding round, what sort of industrial policy is most efficient, AI fighter jets, and more. Roughly 2/3rds of the content is paywalled, so for full access become a paid subscriber. If you are a paid subscriber, feel free to suggest a topic for a future newsletter in the comments below.
One other item of note, in this week’s essay Energy Cheat Sheet, there were a couple errors:
Joule should have been defined as the energy needed to accelerate a 1-kilogram mass at 1 meter/second^2 over a distance of 1 meter, not 1 meter/second.
The energy consumption by country table had incorrect per-capita consumption values.
These have been fixed on the website.
Commercial fusion reactor
Earlier this year I wrote about fusion power, and talked about some of the startups that are currently trying to bring it to market. Now one of them, Commonwealth Fusion Systems (which has previously raised over $2 billion in venture capital), has progressed to the point where they’re making plants for a commercial reactor, the world’s first. From their press release:
The new ARC fusion power plant will support economic development and the clean energy goals of Virginia. The project is expected to generate billions of dollars in economic development in the region and create hundreds of jobs during the construction and long-term operation of the power plant. ARC will generate about 400 megawatts of electricity — enough energy to power large industrial sites or about 150,000 homes.
CFS is currently completing development of its fusion demonstration machine, SPARC, at its headquarters in Devens, Massachusetts. SPARC is expected to produce its first plasma in 2026 and net fusion energy shortly after, demonstrating for the first time a commercially relevant design that will produce more power than consumed. SPARC paves the way for ARC, which is expected to deliver power to the grid in the early 2030s.
Briefly, Commonwealth is using a tokamak design for their reactor, probably the most studied and developed type of fusion reactor. (The huge ITER test reactor being built in France is also a tokamak.) Commonwealth’s design is based on using a novel type of magnet made from superconducting magnetic tape, which should make it much cheaper to build than previous tokamaks.
Making NEPA less burdensome
The National Environmental Policy Act (NEPA) is the law that requires any major federal government action to have an environmental impact statement analyzing its impacts on the environment. As I wrote in my earlier essay on NEPA, “ These statements (which can be thousands of pages long and take years to prepare, and must be completed before the project can start), along with the broader perception that the NEPA process is slow and unwieldy, has made NEPA the frequent target of criticism and reform efforts.”
A major way that NEPA slows down projects is that it provides an avenue for people to file lawsuits by claiming that these impact statements weren’t done thoroughly enough. An op-ed in the Wall Street Journal has an interesting suggestion for how to mitigate this problem: courts should decide not to apply NEPA to places where there’s already an environmental law regulating the impact:
But establishing a predictable principle to guide future decisions about infrastructure development and prevent further litigation will be difficult. Litigants will have to parry a barrage of unpredictable hypotheticals trying to determine what constitutes the relevant proximate effects.
So before going down that rabbit hole, the justices might first consider the National Environmental Policy Act’s original threshold for review. NEPA directs federal agencies undertaking major action to consider “presently unquantified environmental amenities and values.” When NEPA was enacted in 1970, little in the environmental domain was quantified. More than 50 years later, almost everything is.
Since 1970, Congress has enacted at least 25 environmental and resource-protection statutes, compounded by a vast array of state, county, local and tribal laws. These laws cover every imaginable environmental topic. They amount to hundreds of thousands of technical rules established by countless experts constantly reviewing, monitoring, inspecting and enforcing every last one of them. In other words, there is very little that is still “unquantified” by NEPA’s standards. If something can be studied and regulated, there is probably an agency already doing so.
So when the court considers a clear and practical boundary for NEPA analysis, it should conclude that an agency need not consider environmental impact already regulated by an existing law.
Boom funding
Boom Technology, a company trying to build a supersonic airliner, received $100 million in new funding from an impressive list of investors, including Paul Graham, Sam Altman, and Michael Moritz (chairman of Sequoia Capital, arguably the most successful VC firm). Paul Graham stated on twitter that “I invested more in Boom than I've ever invested in a startup before. But this company is important for America. They'll also make a huge amount of money if they succeed. No one else is anywhere near having a supersonic airliner.”
I have no particular expertise in evaluating aerospace technology, but my outside view is that the chances for Boom still look bleak. Boom founder Blake Scholl noted that this was a down round/recapitalization (ie: the company is valued less than the last time it raised money.) Boom is performing test flights with their XB-1 testbed, and should take it supersonic soon, but from what I understand this is sort of a demonstration plane that has no real relationship to their ultimate passenger jet. And the fact that Boom couldn’t get any of the Big 3 engine manufacturers (Rolls Royce, GE/Safran, or Pratt and Whitney) to develop their jet engine still seems like a bad sign. Boom is using Kratos to design their engine, a defense contractor which “is focused on the development and production of small, affordable, high-performance jet engines for cruise missiles and unmanned aerial systems (UAS).”)
Developing a commercial jet engine at all has traditionally been extremely difficult and expensive. Pratt and Whitney spent $10 billion over 20 years to develop their new geared turbofan. Development costs for CFM’s (a joint venture between GE and Safran) LEAP engine are hard to find, but we can infer that they’re similarly high based on the fact that it took CFM more than a decade to break even after introducing it, even as it sold billions of dollars of them. Rolls-Royce went bankrupt in 1971 due to difficulties in developing an engine for the Lockheed Tri-Star. And these are the experts in developing commercial jet engines. I’m not particularly optimistic about the odds of a defense contractor who doesn’t have a background in building them, with “only” $100 million to spend (though presumably they’ve made some progress already).
It’s also notable that previous supersonic transport efforts often tried to minimize the amount of engine development required, probably to minimize technical risk in an already risky program. The Concorde modified an existing Rolls Royce Olympus engine, and the planned Boeing 2707 and Lockheed SST would have used a modified GE YJ93 and Pratt and Whitney J58, respectively. I would be a lot more optimistic about Boom if they weren’t also having to develop a jet engine along with the aircraft itself.
It’s of course possible for an upstart to come in and develop incredibly impressive aerospace technology that blows away the incumbents, with SpaceX being the obvious example. So you could argue that prior engine and aircraft development costs just aren’t that relevant. But a) building jet engines and commercial aircraft is probably harder than building rockets, b) the structural incentives in the rocket industry probably meant there was more of a “competency gap” between what incumbents were doing and what a motivated, skilled startup could achieve than there is in commercial jet engines, and c) with Boom it's not an upstart building the engine, it’s an existing defense contractor.
I hope I’m proved wrong! It would be great if we had supersonic transport, but I’m not sure that Boom will be the company that gets us there.
For more on the history of supersonic transport, you can read my previous essay on the topic.
Airships
Not all interest in new air transportation technology is in going extremely fast. Some folks think there’s a lot of promise in airships as a method of cargo transportation. Eli Dourado (who used to work at Boom) lays out the case for them in this post from 2023:
The physics of airships are unbelievably seductive.
All aircraft are subject to four forces: thrust and drag in the direction of travel, and lift and gravity in the vertical direction. For an aircraft in steady flight, the vertical and horizontal forces are in balance.
A useful way to summarize the performance of an aircraft is via the lift-to-drag ratio.1 If an aircraft can generate more lift and/or produce less drag, the performance of the aircraft is higher.
For an airship, which gets lift from lifting gas (aerostatic lift) instead of from wings (aerodynamic lift), the amount of lift is proportional to the volume of lifting gas. The drag is proportional to some combination of cross-sectional area and wetted area—in any case, it increases with area.
The performance of an airship, therefore, is proportional to volume divided by area. As an airship increases in size, both the volume and the area of the airship increase, but the volume always increases faster than the area. The volume is a function of length cubed, while the area is a function of length squared.
This simple square-cube law means that, in principle, the performance of an airship gets better as it gets bigger. Forever.
If your airship performance isn’t good enough, just double it in size. The lift will increase by a factor of 8, the drag will increase by a factor of 4, and the lift-to-drag ratio will therefore double. Still not good enough? Do it again. 🤯
To do cargo airships right, we need to make the biggest flying objects ever created. A modern cargo airship would make the Hindenburg puny by comparison.
The basic idea seems to be that there’s room in the international cargo market for a transportation mode faster than an ocean-going ship but slower than a plane. (Interestingly, I’ve heard this same justification used to advocate for nuclear-powered ships that are faster than conventional ships.)
There’s a few companies trying to make airships happen. Airship Industries was incorporated in the US earlier this year. In the UK, Hybrid Air Vehicles, which has been around since 2007, is building a new factory to manufacture airships that could carry 100 passengers or 10 tons of cargo.
Industrial policy
Many current economic and political concerns fall under the heading of “questions about industrial policy”: things like what the US should do to bring back manufacturing jobs, or reshore semiconductor manufacturing, or how to ensure the US has a strong defense production base.
One key question about industrial policy is, where should you devote your efforts? Where do you get the biggest bang for your government buck? The Carnegie Endowment for International Peace lays out a possible framework for how to think about this in the clean energy sector:
We propose a supply chain resilience framework that evaluates a clean energy sector on four broad measures: economy-wide impacts, competitiveness, supply chain risk, and national security. The four factors address the following questions:
Economy-Wide Impacts: How significant is the sector to the overall economy? What is the risk that a supply shock would have significant consequences?
Competitiveness: Can the sector become globally competitive? Could it eventually become profitable without subsidies and supply foreign markets?
Supply Chain Risk: How diversified is supply? Can a small number of actors (states or firms) exert significant influence over production in the United States and allied countries? How exposed is the US economy to geopolitical risks in the sector’s supply chain?
National Security: Is the technology needed for national security applications?
Using this framework, battery manufacturing appears to be a much better target for US industrial policy efforts than solar PV manufacturing:
On balance, the batteries sector has much larger economic impacts, more direct national security applications, and more competitiveness potential than the solar power sector. While the solar sector currently out-performs battery manufacturing in terms of revenue and employment statistics, the economy-wide impacts and forward-looking indicators included in the framework favor the batteries sector.
The solar sector’s current lead on revenue vis-a-vis batteries is slim and likely to fall over the medium-term, particularly considering China’s significant overcapacity and manufacturing pipeline for PV modules and upstream components. As the leading solar analyst Jenny Chase of BNEF puts it, “solar is a horrible business.” Regarding employment, the batteries sector offers greater growth potential because its value chain feeds into the EV and automotive sectors, critical manufacturing industries which alone employ more than three times the solar sector’s workforce across manufacturing, construction, and installation.