The Gas Turbine: The final revelation in the pantheon of prime movers. A mega 🧵

Rockets, in the form of gunpowder charges rammed into bamboo, predate the Magna Carta. Water wheels powered medieval grain mills.

Steam piston engines drove the industrial revolution and Parson’s 1894 steam turbine continues to deliver most of the world’s electricity generation.

In the late 19th century Otto’s and Diesel’s internal combustion engines began to reorganize transportation, agriculture, warfare and bulk shipping of commodities.

The gas turbine emerged only in the 1930s. It is the most recent and the last prime mover. It has subsequently become the undisputed champion of global aviation and increasingly a dominant source of dispatchable electricity on grids around the world.

Demand for gas turbines is now surging as AI data centres require rapid additions of baseload power. John Barber patented a recognizable gas turbine cycle in 1791, describing a compressor, a combustion chamber, and a turbine wheel in sequence. John Brayton worked out the thermodynamic cycle that still bears his name in 1872. By the time Frank Whittle ran his first jet engine prototype in 1937, engineers had been sketching versions of the same concept for 65 years.

A gas turbine is, at its core, a device that compresses air, adds fuel and combusts it to produce extremely hot gas to spin a turbine. As engineers push the thermodynamic limits through hotter temperatures the engineering reality is that the hot gasses leaving a modern combustor are well beyond the melting point of the alloys from which the turbine blades are made.

The compressor in a large commercial engine reaches pressure ratios above 40:1, requiring blade geometries machined to tolerances measured in microns across components spinning at thousands of revolutions per minute. In aviation applications the containment structure must be light enough to fly and strong enough to survive a blade release without sending a fragment through a fuselage.

The extreme safety and reliability requirements in aviation and power generation impose a slower pace in innovation cycles reminiscent of the nuclear industry. In the end the gas turbine’s limits are defined by the cumulative materials and manufacturing knowledge required to operate at the edge of its thermodynamics. These factors determine who can build it, and why it is one of the few technologies that the West still decisively dominates, for now.

The following essay is based on a conversation on the Decouple Podcast with Dr. David Helmer, a veteran of GE Global Research and the American Society of Mechanical Engineers (ASME) K-14 gas turbine heat transfer committee.

Understanding why this Uranium cycle may not follow the same script as previous cycles requires understanding something fundamental:

Uranium is a commodity unlike any other, governed by market mechanics that have no real parallel in oil, gas, or industrial metals.

The history of uranium investing is largely a history of analysts importing mental models from those markets and being destroyed by them.

Grant Isaac, President and COO of @Cameco Corp and a former dean of the Edwards School of Business at the University of Saskatchewan, laid out that case in a recent conversation on Decouple. What follows draws on that interview as its primary analytical frame.

A thread🧵 (full essay on decouple.media substack) 1/ Uranium equities have had a strange few years.

The stocks of major producers have surged, junior developers have attracted capital at valuations that would have seemed delusional a decade ago, and the long-term contract price has moved steadily upward without the violent reversal that ended every previous uranium bull market on record.

Investors who lived through prior cycles keep waiting for the blow-off top. It has not come.

The standard explanation is that nuclear power is back.

After a decade of retreating political support following Fukushima, governments across the western world have rediscovered that a 24-hour, carbon-free, energy-dense power source is not something you can replicate with wind turbines and battery storage.

Reactor life extensions, phaseout reversals, a Chinese nuclear construction boom, and corporate power purchase agreements from data centre operators hungry for firm baseload have all landed within a compressed window.

The demand story is real.

But demand alone does not explain why this bull has behaved so differently from its predecessors. Previous uranium cycles also had credible demand stories.

The 2005-2011 bull had a nuclear renaissance narrative, a supply shock from the Cigar Lake mine flooding and China’s sovereign contracting program driving long-term prices. It still collapsed.

X-Energy's Immodest IPO: A mega thread🧵

1/ X-Energy was listed on the Nasdaq under the ticker “XE” on April 24th, raising $1.02 billion with shares surging 30.9% on debut to give the company a valuation of $11.9 billion.

The bold claim made by @xenergynuclear CEO Clay Sell in the present tense that “We make it easy to build nuclear power plants” will certainly be put to the test. Extraordinary claims require extraordinary evidence and that evidence has yet to be produced.

Lets examine what China's 50-year pebble bed high-temperature-gas-reactor program can teach us about the valuation of the West's most recent publicly traded reactor company. 2/ X-Energy's pitch is that Dow Chemical @DowNewsroom as anchor customer, @amazon as both lead equity investor and holder of power purchase commitments for more than 5 GWe, and Centrica as a UK utility partner, all anchored to an 80 MWe pebble-bed high-temperature gas-cooled reactor.

The embedded assumption in X-Energy’s $11.9 billion valuation is that American startup dynamism can compress what has been for China, the world’s most capable nuclear industrial state, a 50-year institutional journey into a single first-of-a-kind pebble bed high temperature gas reactor construction project.

In sectors where design, capital, and IP are dominant, that assumption is often correct. China’s pebble-bed program, however, illustrates why even “advanced nuclear” is not one of those industries.

Nuclear Waste Reprocessing: A Mega-🧵1/20!

1/ Imagine a technology that could take the most feared byproduct of nuclear power and transform it into fuel: burning the long-lived actinides that make spent fuel a supposed million-year liability down to fission products that decay to background radiation within a few centuries.

All of this while extracting enough energy from the 95,000 metric tons of nuclear waste sitting in pools and dry casks across the United States to power the entire country for 150 years.

That technology has been demonstrated. At Idaho National Laboratory, the Experimental Breeder Reactor II (EBR-2) ran for 30 years on metallic fuel cycled through an attached electrochemical reprocessing facility, closing the loop in exactly the way the vision describes: spent fuel in, fresh fuel out, waste reduced to a centuries-scale rather than geological-scale problem.

The physics and engineering has been proven at pilot research scale. It has, however, failed to scale. 2/ What did scale commercially looks considerably different. La Hague, the world’s largest reprocessing facility, has operated for the better part of a century. France built it not out of a romantic attachment to the closed fuel cycle but out a perceived energy security necessity: Almost no domestic fossil fuels, and, in the postwar decades, uranium supply chains that looked dangerously thin.

French reprocessing works. It has extended the country’s uranium utilization, deferred the need to mine fresh uranium by putting depleted enrichment tails and recovered plutonium back to work as MOX fuel, and given Paris a degree of fuel cycle independence that looks increasingly valuable as the theme of energy security once more rises to prominence with the Iran war and the closure of the Strait of Hormuz.

What French reprocessing does not do is meaningfully reduce the volume of material destined for deep geological disposal.

But the La Hague program is not EBR-2. It is a pragmatic industrial process operating within the constraints of thermal reactor physics, and those constraints are severe.

The gap between what France actually achieves and what the closed cycle promises is the central story of nuclear reprocessing, and it begins with understanding what is actually sitting in those spent fuel pools.

Europe Forgot the Lesson the 1970s Oil Shocks Once Taught

The continent answered with reactors, pipeline diplomacy, and offshore drilling, then spent three decades neglecting and dismantling everything it had built. a mega🧵inspired in part by my conversation with Doomberg.

The European response to the OPEC embargo was an impressive mobilization that moved decisively and pragmatically taking advantage of the unique conditions available throughout the bloc.

France moved decisively launching the The Messmer Plan in direct response to the oil shock. It remains the fastest large-scale nuclear buildout in history.

France had little domestic oil, but it had everything else the program required: a large corps of state-trained engineers produced by the Grandes Écoles, heavy industrial capacity rebuilt under the postwar dirigiste economic model, and a nationalized utility in Électricité de France (EDF) already accustomed to executing at the direction of the state rather than waiting on market incentives.

Its political class drew the logical conclusion: electrify aggressively around a domestic nuclear base, using a standardized reactor designs that a purpose-built supply chain could replicate at pace.

Space heating, water heating, rail and significant portions of industrial process heat were shifted onto the grid as the fleet came online, deliberately substituting domestic electrons for imported hydrocarbons across as much of the economy as the technology of the era allowed.

The result over roughly twenty years was 54 operating reactors, an electricity system generating around 75 percent of its output from nuclear, net electricity exports to neighbours who had made different choices, and as an unintentional side effect a per-capita carbon footprint in the power sector that remains among the lowest in the developed world. 2/ Britain and Norway answered through a different channel with the same underlying instinct.

The North Sea had yielded promising geological discoveries before the embargo, but the post-shock period transformed offshore petroleum into a central national project on both sides of the median line.

The technical obstacles were formidable: deepwater fields in rough northern seas, novel platform engineering, supply chain development for equipment categories that had barely existed before.

Both governments pressed through, operating under a governing assumption that sounds almost exotic in Brussels today, namely that a country should develop strategically important resources under its own waters when those resources can materially improve national resilience.

Within roughly a decade Britain had moved from significant oil importer to net exporter. Combined British and Norwegian output contributed materially to the global oil supply glut that emerged through the 1980s. The glut that always follows a supply shock once investment finally responds to price signals was this time in part European.

Ras Laffan and the Arctic Metagaz: How two drones changed the calculus of global LNG dependence

A Mega 🧵based on my @DecoupleMedia conversation with @SStapczynski

Qatar is roughly the size of Connecticut, a narrow peninsula jutting into the Persian Gulf on the wrong side of the Strait of Hormuz. For decades, this geography was considered a manageable risk, because Qatar had cultivated a reputation for perfect reliability.

When Japan shut down its reactor fleet after Fukushima in 2011 and scrambled to replace the lost generation with gas, Qatar delivered. When spot and short-term suppliers, including an Italian energy major and at least one trading house, voided their flexible contracts with Pakistan during the 2022 price spike and rerouted those cargoes to European buyers willing to pay more, Qatar delivered those too.

Then a $50,000 Iranian drone struck Ras Laffan. The attack came in the broader wave of Iranian retaliation for the US-Israeli bombing campaign against Iranian nuclear and military infrastructure. Qatar, which had maintained som

Artic Metagaz on fire near Malte of the warmest relations with Iran of any Gulf state and had served as broker for the first Israel-Hamas ceasefire, was hit anyway.

The strike forced an evacuation of the facility and the first force majeure declaration in Ras Laffan’s history. The complex produces 77 million tonnes per year (Mt/y), roughly 19 percent of the 411 Mt traded globally in 2024. The North Field East expansion, the first of three planned phases that would nearly double Qatari capacity to 142 Mt/y by 2030, was approaching its first commissioning when the drone hit.

That same week, in the Mediterranean, a Ukranian drone boat struck the Arctic Metagaz, a Russian LNG carrier transiting toward the Suez Canal. The ship was not difficult to find. It was on a known route, visible on commercial vessel-tracking platforms, its name painted on the hull.

LNG tankers had already been rerouting around the Cape of Good Hope since the Houthi attacks made the Red Sea dangerous in late 2023, absorbing the extra transit time and cost rather than risk the strait. But no LNG carrier had been successfully struck. The Arctic Metagaz was the first. For Russia, losing one vessel from a fleet of sixteen shadow tankers is not a rounding error.

The two attacks came within days of each other, from different actors hitting different kinds of targets with different customers, but they broke the same assumption. The cascade that followed is not limited to European gas futures. It includes fertilizer plants in Pakistan going dark, rice farmers in Thailand who cannot get diesel, and nine days of reserve supply sitting in South Korean LNG storage tanks.

Nuclear Fuel Is The Swiss Watch of Energy and The Most Sophisticated Industrial Product You've Never Heard About.

Buckle up for a mega-🧵

There is a peculiarity at the heart of nuclear energy that rarely gets the attention it deserves. Every other thermal power plant in history destroys its fuel.

Coal goes in as a black rock and comes out as CO2, water vapor, and ash. Natural gas barely leaves a trace at all, just heat and gaseous combustion products dispersed into the atmosphere.

The fuel is gone, irreversibly transformed, its chemical identity obliterated in the furnace.

Nuclear fuel does almost none of that. The fuel elements that go into a reactor and the fuel elements that come out are, to a first approximation, the same material in the same geometry, sitting in the same place.

A spent fuel assembly pulled from a reactor after six years of operation looks nearly identical to the fresh one that went in.

The mass has changed by a tiny fraction of a percent, nuclear alchemy has occurred in which half the periodic table has been generated in the form of fission products within the ceramic pellets but the volume and geometry is essentially identical.

This one fact, that nuclear fuel must be preserved rather than destroyed, that the job of every layer of every system surrounding the core is to maintain the integrity of a material through years of radiation bombardment and extreme temperature gradients, shapes much of nuclear engineering.

It explains the cladding materials, the obsessive quality control in fabrication facilities, and the decades of slow, painstaking improvement that have transformed a fleet that routinely operated with failed fuel elements into one where a single leaker triggers a formal investigation.

I spent a long conversation with Michael Seely, the @AtomicBlenderYT, a nuclear enginner with a focus on fuel, going through what nuclear fuel actually is, how it is made, why it fails, and how the industry learned to prevent those failures.

What follows is my attempt to synthesize that conversation into something useful for anyone who wants to understand nuclear from the inside out. What the Fuel Actually Is

The commercial nuclear fuel cycle, in its conventional form, converges on a single material: uranium dioxide, or UO2.

Regardless of reactor type, whether you are talking about a pressurized water reactor in France, a boiling water reactor in Japan, or a CANDU in Ontario, the fuel pellet sitting at the centre of the fuel rod is almost certainly a dense ceramic cylinder of uranium dioxide roughly the size of a fingertip.

1/ Energy, industry, and sovereignty are inseparable. If Europe wants to be a truly independent pole in an emerging multipolar world, it must reindustrialize—not deindustrialize. That starts with reversing nuclear phaseouts. 🧵 2/ Germany, the industrial powerhouse of the EU, built its economic might on two things:
⚡ Cheap nuclear power
🔥 Cheap Russian gas
Now that Russian gas is gone, nuclear must return.

Why is China electrifying its economy at such dizzying speeds?

3 words

Straits of Malacca.

While the US leans into its hydrocarbon advantage, China is decoupling from severe oil dependence & geographical vulnerability. a 🧵based on @DecoupleMedia w @pretentiouswhat When Western climate analysts look toward China, in some sense they see the future, where fantasies of large-scale renewables deployment and EV adoption are playing out.

But far more than climate considerations, the geopolitics of oil dependence are shaping China's energy future. With 80% of its oil imports flowing through the narrow Strait of Malacca, China faces an existential vulnerability.

WE’VE GOT TO TALK ABOUT FUKUSHIMA TRITIUM RELEASES.

TL:DR the fear is misplaced.

Tritium is an isotope of hydrogen It binds H and O to make HTO, tritiated water.

It is created naturally by cosmic rays in the upper atmosphere as well as in nuclear power plants.

https://twitter.com/hanakomontgome1/status/1627986555444039680

Tritiated water behaves just like H2O and is excreted from the body quickly with a biological half life of 3.5 days. For this reason it doesn’t bioaccumulate up the food chain and diffuses and dilutes rapidly in lakes and oceans.

Its all doom and gloom for Nuclear in @BentFlyvbjerg's new book "How Big Things Get Done"

But did he miss some nuance when conflating the Korean/UAE collaboration which will have delivered four 1400MW reactors in 12 yrs with the unfolding fiasco of Vogtle 1/ In the book @BentFlyvbjerg and @dgardner contrast the Guggenheim museum and the Sydney Opera house to draw important lessons from two very cutting edge buildings. 2/

NUCLEAR WASTE IS INCREDIBLY DANGEROUS!

Unshielded & fresh out of the reactor exposure for seconds would result in certain death.

But somehow there has not been a single documented death from storing civilian nuclear waste. Ever.

Here's what you need to know: a 🧵 We make dangerous things, like nuclear waste, safe.

Consider civil aviation.

In 2019, 4.5 billion passengers took 42 million flights worldwide flying 900km/hr at 30,000 feet in thin skinned, pressurized aircraft often over vast oceans.

There were only 289 fatalities.

A Canada-Germany Hydrogen Scandal?

Beyond a potential political scandal lies a very real energy scandal. Listen Now!

James Fleay, an Australian engineer & project manager, joins @decouplemedia to discuss. 1/

@JavierBlas @DoombergT @BurggrabenH

anchor.fm/chris15401/epi… twitter.com/i/web/status/1… This Hydrogen Alliance is coming under increasing scrutiny due to allegations of a conflict of interest arising out of the Premier of Newfoundland, Andrew Furey's luxury trip to a lodge owned by Canadian billionaire John Risley this summer. 2/

⁦@JonathanWNV⁩ is out of line with the world’s top Climate activist ⁦@GretaThunberg⁩

Greta called on Germany not to close its nuclear as it pivots back to coal.

Wilkinson claims that gas is not used for electricity generation in Ger. This is factually incorrect. 1/ Here is Germany’s electricity generation by source in 2021. Gas was a significant part of their electricity. EU Natural Gas reached an all time high of 345 euro/MWh on the TTF in March of 2022 which has driven even more coal burning as a way to ration gas use on the grid. 2/

Is Nuclear Energy Just Too Risky? A 🧵.

As doctors we explain the risks & benefits of treatment plans on a daily basis. The risk/benefit profile of nuclear energy is clear. Nuclear is extremely safe, our lowest CO2 energy source & is essential to reaching our climate goals. 1/ After the terrorist attacks of 9/11, many Americans felt that flying was too risky and started driving instead. 2/

Thread: Dan Campbell was one of the workers who operated Nanticoke, North America's largest coal facility. He wasn't sure what to think about climate change & whether his workplace was contributing to childhood asthma or shortening the lives of Ontarians from air pollution 1/ He had worked hard to become very good at his job, enjoyed the challenge of his work and took pride in keeping the lights on across the province. 2/

“CHRIS KEEFER, a physician and part-time pro-nuclear energy advocate will be meeting with MPs and holding a press conference in Ottawa today, in a bid to put pressure on the government to change its energy policy.” 1/ “Nuclear energy was arguably given short shrift in the government’s recently-released greenhouse gas emissions reduction plan for 2030.” 2/

Is a “Just Transition” away from fossil fuels towards a decarbonized energy system technology specific? The basket of available & scalable technologies: Wind, Solar & Nuclear each come with characteristics that determine wages, levels of unionization & security of employment.🧵1/ When #GreenNewDealers imagine the jobs of a clean energy transition, they often nostalgically harken back to the post war era when generations of blue collar workers could support families on a single income in a unionized workplace & afford to send their kids to college. 2/

I was recently featured in a @simonahac “gotcha tweet” regarding the lifespan of renewable energy projects. There are some major problems with @simonahac's reasoning which I will go into below. I’ll avoid the mudslinging and name calling and stick to the facts. Thread 2.) TL:DR The renewables industry themselves and independent organizations claim an average lifespan of wind of 20 years and of solar panels of 25-30 years. I will argue below that the solar numbers are likely exaggerated. twi-global.com/technical-know…
greenbiz.com/article/what-w…

@AdamBlazowski is a founder of the Polish pragmatic environmentalist group FOTA4Climate. FOTA came together in 2018 out of a frustration with the limits of the mainstream environmental movement. Check out the interview on the @DecouplePodcast anchor.fm/chris15401/epi… 2.) @fota4climate includes a broad spectrum of experts and activists ranging from energy analysts to herpetologists and characterizes itself as a “tech agnostic group.”

I am joined by @Heather_mom4nuk on the @DecouplePodcast. Heather is the co-founder of Mothers for Nuclear. She is a materials scientist, nuclear reactor operator at Diablo Canyon and a lifelong environmentalist. anchor.fm/chris15401/epi… In the words of their website @moms4nuclear is an organization of environmentalists, humanitarians, and caring human beings.