The large transformer shortage has been a problem for years. Large transformer making is a craft, where the winding supports are made of hardwood, like furniture, and wound by hand. Then the windings go into a case that's an oil tank.
The build teams aren't that big - 30-50 people. The main barrier to entry is that it takes people who know how to hand-build big transformers. Utility buyers want a supplier who's going to be around half a century from now, since these things last that long.
Here's a summary of the market, from a transformer maker in China.[1]
Here's an AI-generated fake video of large transformer manufacturing. It's about half wrong.[2] But right enough to be worth watching. I'd like to see the prompts for this.
Virginia Transformer is the US's biggest maker of large transformers.[3] They advertise their "short lead times" of two years. The margins are low, and makers don't want to go idle between orders. This is a problem with much heavy machinery. It could be built faster, but when you catch up, everybody gets laid off and the factory sits idle. There goes your profit margin.
It's a generic problem with flat demand in heavy industry. Shipbuilding, bridges, nuclear reactors - when the production backlog runs down and the factory goes idle, the factory dies. So do the companies that feed specialized parts into the process.
This would be a great opportunity for the government to get involved.. Tell them to just make two of every order they have now and the government will buy the second one at whatever price the customer is paying. Put the spares in a strategic repository and sell them at “cost” to whoever wants them. Would be a much better use of a few billion dollars than some asinine Star Wars II or another half a trillion into the war maw.
> So how did we get to a point where one component can hold trillion-dollar industries hostage? Turns out, a quirk of history made the entire world’s electricity systems reliant on transformers.
> At the end of the 19th century, when electricity was just starting to become a commercial source of energy, two businessmen fought to control its future in what came to be known as “the war of the currents.” Thomas Edison promoted the use of direct current (DC) and George Westinghouse, inventor and industrialist, was convinced that alternating current (AC) would prove more practical.
> In a clash of personality, finance and some genuine technical advantages, Westinghouse won out and the world has been mostly stuck with using AC as a means of generating and transmitting electricity. Transformers are necessary to make the AC system work.
This entire section is a glaring load of nonsense and needs to be removed. We had to start with AC for a variety of technical reasons, the main one being that boosting DC voltage pre-switching technology was impossible. DC cant pass through a transformer unless it is converted to some form of AC, usually in the form of PWM square waves these days. Before the invention of the mercury arc rectifier (And later valve) in 1902 you had boost DC using mechanical methods: generators. The problem there is physical, they did not have the ability to insulate the generator windings at high voltage potentials. They also had problems with DC voltages over 2000 volts on commutators [1] citing excessive arcing. Commutators are also a limiting factor in machine size as beyond several MW they dissipate too much power. So with all this the highest practical voltage for a DC grid using early electrical machinery is around 2 kV. Now imagine all that mechanical complexity on the distribution end. Meanwhile, early AC transmission was already in the tens of kilovolts: 11/22/33 kV (multiples of the early Edison 110 volt standard.)
As for the whole war of currents, I feel it is vastly overstated and was more a public spectacle than serious scientific dispute. It was already known from early on that AC was the future thanks to its ability to easily be transformed to higher voltages for transmission and back again with no moving parts. The "war" was likely Edison marketing to sell off the remaining inventory less desirable DC machinery.
Yes this is the most glaring issue. There also two disconnects later in the article: at the end it laments how china has been increasing transformer manufacturing but the US government has done nothing. Then in the next sentence its mentions trumps tariffs have increased transformer costs, I. E. Government action to increase domestic production. It also glosses over the new DOE rule on how transformers are made…so maybe there is a larger story there relevant to the lack of supply.
The early limit was because high voltage DC required producing it at the generator, whereas you could produce high voltage AC by generating at a lower voltage and then stepping it up with a transformer for long distance transmission.
The rules are changing because of switchmode voltage conversion, using transistors to switch the voltage at a high frequency, where the magnetics (transformers, inductors) can be much smaller and more efficient, then converting back to DC. This is how virtually all smaller power supplies have been made for years, the only question (which I don't know) being how far along we are at reaching the voltage levels of long distance transmission in this way.
I'd think that hustling us towards DC with electronic voltage conversion would be a reasonable strategic goal for dealing with the transformer problem, worthy of support by a government.
That link talks about 5MW 35kv AC / 800v DC converters.. completely different thing, they try to sell a single-source PV invertor-to-35KV AC solution first, then 35KV to 800V DC second, to have a sorta complete solution of PV-to-datacenter. And it's only 5MW. And only 35KV AC. For moving 100MW even over a few km you would need 110KV at least. I think. An overhead wire can handle about 600A of current, that's the physical limit and the reason for kilovolts there.
Consider also that there is nothing existing in transmission and switching gear certified for HVDC it being rare one-off projects so far, while AC is ubiquitious, more-or-less mass-produced and many people are trained in its maintenance.
If you are not ready to lock yourself in a bunker after reading the article and watching that short, I strongly suggest you consider the inclined plane.
You’d better do it now. Very few locks work in the absence of transformers, springs and inclined planes.
Possibly the easiest way to bring any metropolitan area or region into the Stone Age for unknowable amounts of time is simply to destroy large, bespoke transmission (rather than distribution) transformers. Crazy people shooting out the cooling systems have done this several times.
Meaningful grid security means these items need rapid, standardized, domestic production capacity and cold spares distributed offsite and ready to be deployed should anything happen to ones in use. These are critical items that must not be neglected to reactive actions disaster recovery.
An article that deeply buries the lede under elementary facts about electrical transmission.
Transformers are made in specialized factories and use specialized components made in even more specialized factories. Expanding production requires not just immediate demand but commitment to future demand because a factory is a very expensive thing. The big thing is that increased demand often involves a demand that won't continue for a long period of time.
You could see the same thing with both masks and vaccines during covid - ramping up ten factories to meet a temporary demand would be very expensive.
They're also heavy. The tragedy of Russia destroying the Ukrainian An-225 was it was one of the only ways to move very big grid scale transformers on short notice.
The large transformer shortage has been a problem for years. Large transformer making is a craft, where the winding supports are made of hardwood, like furniture, and wound by hand. Then the windings go into a case that's an oil tank.
The build teams aren't that big - 30-50 people. The main barrier to entry is that it takes people who know how to hand-build big transformers. Utility buyers want a supplier who's going to be around half a century from now, since these things last that long.
Here's a summary of the market, from a transformer maker in China.[1]
Here's an AI-generated fake video of large transformer manufacturing. It's about half wrong.[2] But right enough to be worth watching. I'd like to see the prompts for this.
Virginia Transformer is the US's biggest maker of large transformers.[3] They advertise their "short lead times" of two years. The margins are low, and makers don't want to go idle between orders. This is a problem with much heavy machinery. It could be built faster, but when you catch up, everybody gets laid off and the factory sits idle. There goes your profit margin.
[1] https://energypowertransformer.com/2025-u-s-power-transforme...
[2] https://www.youtube.com/watch?v=ZVVCCG0KkaE
[3] https://www.vatransformer.com/shortest-lead-times/
You'd think if it's causing this much of a problem, there would be money available.
It's a generic problem with flat demand in heavy industry. Shipbuilding, bridges, nuclear reactors - when the production backlog runs down and the factory goes idle, the factory dies. So do the companies that feed specialized parts into the process.
This would be a great opportunity for the government to get involved.. Tell them to just make two of every order they have now and the government will buy the second one at whatever price the customer is paying. Put the spares in a strategic repository and sell them at “cost” to whoever wants them. Would be a much better use of a few billion dollars than some asinine Star Wars II or another half a trillion into the war maw.
> So how did we get to a point where one component can hold trillion-dollar industries hostage? Turns out, a quirk of history made the entire world’s electricity systems reliant on transformers.
> At the end of the 19th century, when electricity was just starting to become a commercial source of energy, two businessmen fought to control its future in what came to be known as “the war of the currents.” Thomas Edison promoted the use of direct current (DC) and George Westinghouse, inventor and industrialist, was convinced that alternating current (AC) would prove more practical.
> In a clash of personality, finance and some genuine technical advantages, Westinghouse won out and the world has been mostly stuck with using AC as a means of generating and transmitting electricity. Transformers are necessary to make the AC system work.
This entire section is a glaring load of nonsense and needs to be removed. We had to start with AC for a variety of technical reasons, the main one being that boosting DC voltage pre-switching technology was impossible. DC cant pass through a transformer unless it is converted to some form of AC, usually in the form of PWM square waves these days. Before the invention of the mercury arc rectifier (And later valve) in 1902 you had boost DC using mechanical methods: generators. The problem there is physical, they did not have the ability to insulate the generator windings at high voltage potentials. They also had problems with DC voltages over 2000 volts on commutators [1] citing excessive arcing. Commutators are also a limiting factor in machine size as beyond several MW they dissipate too much power. So with all this the highest practical voltage for a DC grid using early electrical machinery is around 2 kV. Now imagine all that mechanical complexity on the distribution end. Meanwhile, early AC transmission was already in the tens of kilovolts: 11/22/33 kV (multiples of the early Edison 110 volt standard.)
As for the whole war of currents, I feel it is vastly overstated and was more a public spectacle than serious scientific dispute. It was already known from early on that AC was the future thanks to its ability to easily be transformed to higher voltages for transmission and back again with no moving parts. The "war" was likely Edison marketing to sell off the remaining inventory less desirable DC machinery.
1. https://en.wikipedia.org/wiki/Commutator_(electric)
Yes this is the most glaring issue. There also two disconnects later in the article: at the end it laments how china has been increasing transformer manufacturing but the US government has done nothing. Then in the next sentence its mentions trumps tariffs have increased transformer costs, I. E. Government action to increase domestic production. It also glosses over the new DOE rule on how transformers are made…so maybe there is a larger story there relevant to the lack of supply.
> practical voltage for a DC grid using early electrical machinery is around 2 kV.
What is a current (pun!) practical limit?
If a 100MW PV farm and a data center are separated by 1km (20 Olympic pools) - is there a way to avoid AC?
I know there are future solutions [1]
[1] https://techcrunch.com/2025/04/07/former-tesla-exec-drew-bag...
The early limit was because high voltage DC required producing it at the generator, whereas you could produce high voltage AC by generating at a lower voltage and then stepping it up with a transformer for long distance transmission.
The rules are changing because of switchmode voltage conversion, using transistors to switch the voltage at a high frequency, where the magnetics (transformers, inductors) can be much smaller and more efficient, then converting back to DC. This is how virtually all smaller power supplies have been made for years, the only question (which I don't know) being how far along we are at reaching the voltage levels of long distance transmission in this way.
I'd think that hustling us towards DC with electronic voltage conversion would be a reasonable strategic goal for dealing with the transformer problem, worthy of support by a government.
That link talks about 5MW 35kv AC / 800v DC converters.. completely different thing, they try to sell a single-source PV invertor-to-35KV AC solution first, then 35KV to 800V DC second, to have a sorta complete solution of PV-to-datacenter. And it's only 5MW. And only 35KV AC. For moving 100MW even over a few km you would need 110KV at least. I think. An overhead wire can handle about 600A of current, that's the physical limit and the reason for kilovolts there.
Consider also that there is nothing existing in transmission and switching gear certified for HVDC it being rare one-off projects so far, while AC is ubiquitious, more-or-less mass-produced and many people are trained in its maintenance.
Yup. The only thing missing from the writeup is a eulogy for the death of the rotary converter.
My workplace just got rid of a big one, for 60- to 50-Hz conversion, used for testing products that were to be sold overseas.
Well, big as in car engine big, not as in power a city big.
I can think of thousands of components that can hold trillion dollar industries hostage.
I challenge you to name one that cannot and that also makes it into high school curricula or How Things Work.
https://mst3k.fandom.com/wiki/A_Case_of_Spring_Fever_(short)
https://m.youtube.com/watch?v=vzKfAFsbRSk
If you are not ready to lock yourself in a bunker after reading the article and watching that short, I strongly suggest you consider the inclined plane.
You’d better do it now. Very few locks work in the absence of transformers, springs and inclined planes.
Possibly the easiest way to bring any metropolitan area or region into the Stone Age for unknowable amounts of time is simply to destroy large, bespoke transmission (rather than distribution) transformers. Crazy people shooting out the cooling systems have done this several times.
Meaningful grid security means these items need rapid, standardized, domestic production capacity and cold spares distributed offsite and ready to be deployed should anything happen to ones in use. These are critical items that must not be neglected to reactive actions disaster recovery.
https://en.wikipedia.org/wiki/Metcalf_sniper_attack
https://en.wikipedia.org/wiki/Moore_County_substation_attack
https://en.wikipedia.org/wiki/Electrical_grid_security_in_th...
Yet another good reason for at-home solar and storage.
Does very little to offset things like no power for hospitals, refrigerated food distribution, manufacturing of almost anything.
https://archive.today/yn2It
Also https://archive.ph/yn2It
An article that deeply buries the lede under elementary facts about electrical transmission.
Transformers are made in specialized factories and use specialized components made in even more specialized factories. Expanding production requires not just immediate demand but commitment to future demand because a factory is a very expensive thing. The big thing is that increased demand often involves a demand that won't continue for a long period of time.
You could see the same thing with both masks and vaccines during covid - ramping up ten factories to meet a temporary demand would be very expensive.
They're also heavy. The tragedy of Russia destroying the Ukrainian An-225 was it was one of the only ways to move very big grid scale transformers on short notice.
This is a problem in strategic reserve territory.