I think the article has things backwards. It's the shortage of stable demand that is holding back the building of transformers. A transformer factory that can make reliable, efficient, large transformers takes a long time to create because a lot of it relies on institutional memory. But it can be destroyed much more quickly by adverse market conditions and impatient investors.
Remember that the product has a typical lifetime measured in decades, there are huge numbers of large power transformers that have been in near continuous operation for over half a century. When one of those fails it is often more economical to repair it than replace it with a new one but that depends on there being institutions that understand what was done fifty years ago. All this requires the opposite of modern move fast and break things investing.
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.
Governments keep making contracts with megacorp prime contractors, who stiff their suppliers at the first opportunity, instead of the SMEs that are essential to reliable long term capability. It's the bean counter obsession with counting delivered parts as the only basis for payment.
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.
The US Government selling off the helium reserve at cost over two decades effectively capped the global price, even while exploration costs got higher. So exploration was killed, no investments made in better extraction, processing or recycling.
Now that it's gone we're ultra dependent on a by-product of methane extraction and liquification for LNG transport. But most of the helium we extract as natural gas is not separated, as it just gets piped as gas. Helium is getting very very expensive.
You can have the government buy the equipment with the economy goes down, or you can have the government manufacturing it and letting the factory go idle when demand dries down.
But amplifying the orders just makes the problem worse.
The Biden administration invoked the Defense Production Act and used $250m of IRA funds to increase production of grid transformers. Guess what happened when Trump took office.
The problem expressed, I think, that it is not useful to scale up production quickly (or perhaps at all), because a factory catching up on all of their orders means that the factory goes idle. Idle factories can't afford to pay wages, so they lay off some or all of the workers -- and those folks go and find different jobs.
And when they leave, they take their institutional knowledge with them.
So the sustainable goal is to never be idle, and the way to accomplish this is to never catch up.
For an example of how idle factories can go sideways, look at the Polaroid film story: Polaroid closed. Everyone left. Some investors with a big dream eventually bought many of the physical assets that remained.
But owning some manufacturing equipment didn't help them much because the institutional knowledge of producing Polaroid film had already evaporated. They had to largely re-invent the process. (And they've done a great job of that, but it's still not the same film as the OG Polaroid was.)
---
So anyway, suppose the government steps in and simply artificially multiplies transformer orders x2, and pays them fairly for this doubled production. Since transformers are tangible things and we can't just spin up more AWS instances to cover demand, the immediate result is that the "short" lead time on new orders has increased from 2 years, to 4.
That's not seeming to be very ideal. It seems to amplify the problem instead of resolve it.
I suppose that the government could also offer safeguards that would help protect the businesses (including suppliers for parts) once they eventually catch up on orders, and that this might motivate them to scale production sooner instead of later (or never).
Which -- you know -- that isn't unprecedented. As an example: The Lima Army Tank Plant, in Lima, Ohio, is place where I've spent a fair bit of quality time. It still exists and continuously has employees largely because the institutional knowledge of how to build tanks (and a few other war machines) is considered to be too important to lose. During lulls, it mostly just sits there on its expansive site, loafing along repairing stuff that comes in, and waiting for the day when things to turn bad enough that we need to start increasing our number of tanks again.
It needs to keep operating (at any expense), and so with the magic of the government money-printing machine: It does. But it's one of the most actively depressing industrial sites I've ever been to; like the life just gets sucked right out of you before even getting past the entrance gate.
We can certainly extend that kind of thing to transformer production. But should we?
I mean: I've got some MREs in the pantry along with some other shelf-stable food, and I've got some water stored (primarily to fill empty space in the chest freezer for various practical reasons, but it exists). I keep some basic first aid and survival stuff in the car (bandages, space blankets, stuff to catch fish with, stuff to cook with). I've got my camping gear, including a small off-grid solar power system, stored in organized totes that can be loaded up very quickly. And I try to keep a minimum of a couple hundred miles worth of fuel in the gas tank at all times.
I do these things just in case. The bulkiest items see frequent use. None of this cost me very much to buy, or to maintain. And none of these things can replace the lifestyle I've come to expect, but they might be able to buy me some time.
Can we afford to have a spare copy of the hard-to-produce parts of the electrical grid sitting in a warehouse?
Would we even want to rebuild the grid in the same shape if the shit really hit the fan and we had to start it over from scratch?
> 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.
Tariffs don't help onshore manufacturing when they apply to the materials that the manufacturing needs and might evaporate before the manufacturing capability is actually created. Tariffs needs to be applied carefully and consistently to actually encourage this.
Sure, I’m just saying the article was pretty long but pretty short and declarative on the impact of tariffs. Earlier in the article for example is said there was still a factory in the US where the magnetic core material was made.
We had targeted policies under Biden to increase US production of grid components. This entailed invoking the DPA and setting aside millions for manufacturing improvements. Trump paused all that and created blanket tariffs that don’t seem like they’re designed to onshore US manufacturing of these very specific components but do increase all the material costs. This is not an easy thing to fix with dumb tariffs, and it’s really easy to make everything worse.
I’m just noting the article doesn’t have anything specific of value to say about tariff’s. This is not directed at you but rather the reporters: I can read general opinions on tariffs or political parties anywhere; I need details relevant to transformers here to not just ignore other opinions
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.
HVDC and UHVDC are used extensively for long distance transmission, notably for undersea cables and in China, which has made massive R&D investments in the technology in order to shift energy from West to East. Large solar, wind and hydro in the West.
However, DC does not make sense for a radial power distribution network. The article is propagating nonsense.
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.
I've been wondering for awhile about the economics of the AC vs DC grid thing. Historically, AC made a lot more sense because transformers are simple and relatively straightforward to make. But now we have amazing capabilities to handle enormous amounts of power with modern IGBTs and similar power-switching transistors. (A modern high-end EV motor controller, for instance, might be able to handle a megawatt of power. Not continuously, but still.) Is a DC-DC converter now more economically viable than an equivalent transformer? The former is more techincally complicated, but the latter is bulky and requires large quantities of expensive input materials like copper.
transformers are infrastructure, 100% duty cycle with a significant overload capacity that can be 3 times name plate, right there with dams and bridges, and if one developes a fault, realy bad things happen and you get a crater.
There very nature makes them imensely heavy and very compact, all of the equipment used to form the parts is gargantuan, and materials to build them come in units that must be moved by house sized forklifts, consider changing a tire on such a forklift.
Remember that the largest transformers travel on the heaviest rail cars, specials, these things are way heavier than anything else per ft³.
Which gets us to cold,warm, or hot idle, or decomisioning, which are your choices when a huge factory has no work, hot idle means limited production, warm means some of the guys hang out and tinker with stuff, cold means, locked up,no employees but security, as decomisioning something like this has strategic considerations, or should.
The basic problem is easy to grasp, like the mess with charging cords for laptops before it, every large power transformer is a custom design. The fix would be to standardize on a much smaller number of options, and parallel them for the desired loads.
Think of it as analogous to USB-C power, on the megawatt/gigawatt scale. ;-)
People already parallel transformers. That's nothing new but it's usually undesirable because the extra ancillary equipment costs make paralleling more expensive than having a single transformer of equivalent rating if you are building it all at once.
But even fairly small standard specification distribution transformers are custom designs or very short runs. It's not economical to make the same design year after year because the relative prices of copper and core steel vary over time. A design made last year can be uneconomical to make this year because last year copper was relatively cheap so the designer used a lighter core and more copper to achieve the required efficiency. But if this year the copper price has gone up while the core steel price has gone down it would cost more to make the same design while the same specification could be achieved for a lower material cost by making a new design.
The new design is not a new type and for distribution transformers the effort required to design it is of the order of a man hour or two, far less than the difference in material costs.
For very large transformers (megavolt HVDC for instance) the situation is somewhat different and the design can take a very long time. But the opportunities for standardisation are relatively small because the quantity of units in the market is small and the manufacturers and regulators are always chasing ever greater efficiencies.
A far as specifications go there is already quite a lot of standardisation. But standards evolve over time and transformers can last for over half a century so you inevitably end up with a mixture of device types
Also, if one of your paralleled large power transformers fails you can't just buy an off the shelf replacement because no one keeps a stock of items that cost a million dollars each.
Switching to USB-C was trivial because most of the devices involved are essentially consumables with lifetimes measured in handfuls of years ad often much less so the old stuff withers away rapidly. That is not the case with large capital projects such as national electrical networks
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.
"Transformers are necessary to make the AC system work."
This isn't quite wrong but the motivation is backwards: AC is necessary to make transformers work.
1. All grids need to move energy at high voltage and low current to minimize losses.
2. This requires a mechanism to step voltages up and down for transmission.
3. In 1890 the only such mechanism was the transformer.
4. Transformers only work on AC, not DC.
Hence our legacy grid is AC.
Nowadays we have an additional mechanism: Power electronics. Power electronics work on both AC and DC, so transformers with their huge requirements for copper and steel are no longer necessary.
We need to accelerate the transition of our grid to DC because DC grids are simpler and cheaper than AC grids.
Grid-scale power electronics are also extremely niche and expensive, perhaps moreso than transformers. HVDC is used where it has a significant advantage, but ease of conversion is not one of those.
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.
It might be easier for DC transmission components to be standardized. Sure, anything with complex controls has a lot more opportunity to fail to interoperate, but DC gear can often be configured for different voltage ratios and can much more directly control how much current flows where.
Maybe the grid needs a multi-source agreement for equipment like the network industry has for optics.
Also the sewer system backs up after about a week because the pumping and lift stations need power to operate.
The water system shuts down because the tanks aren't reserve supply they're pressure support.
And solar plus storage will keep you running for maybe a week if you're conservative and mostly don't use anything...which doesn't help you if it's months till replacement.
Way stations still need power to accept and refrigerate shipments. Distribution isn't just on trucks - although they could act as a small stopgap that also prevents them from making deliveries while being used as storage.
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.
I think the article has things backwards. It's the shortage of stable demand that is holding back the building of transformers. A transformer factory that can make reliable, efficient, large transformers takes a long time to create because a lot of it relies on institutional memory. But it can be destroyed much more quickly by adverse market conditions and impatient investors.
Remember that the product has a typical lifetime measured in decades, there are huge numbers of large power transformers that have been in near continuous operation for over half a century. When one of those fails it is often more economical to repair it than replace it with a new one but that depends on there being institutions that understand what was done fifty years ago. All this requires the opposite of modern move fast and break things investing.
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.
Governments keep making contracts with megacorp prime contractors, who stiff their suppliers at the first opportunity, instead of the SMEs that are essential to reliable long term capability. It's the bean counter obsession with counting delivered parts as the only basis for payment.
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.
The US Government selling off the helium reserve at cost over two decades effectively capped the global price, even while exploration costs got higher. So exploration was killed, no investments made in better extraction, processing or recycling.
Now that it's gone we're ultra dependent on a by-product of methane extraction and liquification for LNG transport. But most of the helium we extract as natural gas is not separated, as it just gets piped as gas. Helium is getting very very expensive.
You can have the government buy the equipment with the economy goes down, or you can have the government manufacturing it and letting the factory go idle when demand dries down.
But amplifying the orders just makes the problem worse.
> Put the spares in a strategic repository and sell them at “cost” to whoever wants them.
That means that eventually the factory goes idle, when all the demand is serviced by the spares.
The Biden administration invoked the Defense Production Act and used $250m of IRA funds to increase production of grid transformers. Guess what happened when Trump took office.
I'm not sure that this helps.
The problem expressed, I think, that it is not useful to scale up production quickly (or perhaps at all), because a factory catching up on all of their orders means that the factory goes idle. Idle factories can't afford to pay wages, so they lay off some or all of the workers -- and those folks go and find different jobs.
And when they leave, they take their institutional knowledge with them.
So the sustainable goal is to never be idle, and the way to accomplish this is to never catch up.
For an example of how idle factories can go sideways, look at the Polaroid film story: Polaroid closed. Everyone left. Some investors with a big dream eventually bought many of the physical assets that remained.
But owning some manufacturing equipment didn't help them much because the institutional knowledge of producing Polaroid film had already evaporated. They had to largely re-invent the process. (And they've done a great job of that, but it's still not the same film as the OG Polaroid was.)
---
So anyway, suppose the government steps in and simply artificially multiplies transformer orders x2, and pays them fairly for this doubled production. Since transformers are tangible things and we can't just spin up more AWS instances to cover demand, the immediate result is that the "short" lead time on new orders has increased from 2 years, to 4.
That's not seeming to be very ideal. It seems to amplify the problem instead of resolve it.
I suppose that the government could also offer safeguards that would help protect the businesses (including suppliers for parts) once they eventually catch up on orders, and that this might motivate them to scale production sooner instead of later (or never).
Which -- you know -- that isn't unprecedented. As an example: The Lima Army Tank Plant, in Lima, Ohio, is place where I've spent a fair bit of quality time. It still exists and continuously has employees largely because the institutional knowledge of how to build tanks (and a few other war machines) is considered to be too important to lose. During lulls, it mostly just sits there on its expansive site, loafing along repairing stuff that comes in, and waiting for the day when things to turn bad enough that we need to start increasing our number of tanks again.
It needs to keep operating (at any expense), and so with the magic of the government money-printing machine: It does. But it's one of the most actively depressing industrial sites I've ever been to; like the life just gets sucked right out of you before even getting past the entrance gate.
We can certainly extend that kind of thing to transformer production. But should we?
Depends if we intend to reboot after a major geomagnetic event or a war that destroys electrical infrastructure.
Sure.
I mean: I've got some MREs in the pantry along with some other shelf-stable food, and I've got some water stored (primarily to fill empty space in the chest freezer for various practical reasons, but it exists). I keep some basic first aid and survival stuff in the car (bandages, space blankets, stuff to catch fish with, stuff to cook with). I've got my camping gear, including a small off-grid solar power system, stored in organized totes that can be loaded up very quickly. And I try to keep a minimum of a couple hundred miles worth of fuel in the gas tank at all times.
I do these things just in case. The bulkiest items see frequent use. None of this cost me very much to buy, or to maintain. And none of these things can replace the lifestyle I've come to expect, but they might be able to buy me some time.
Can we afford to have a spare copy of the hard-to-produce parts of the electrical grid sitting in a warehouse?
Would we even want to rebuild the grid in the same shape if the shit really hit the fan and we had to start it over from scratch?
> 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.
Tariffs don't help onshore manufacturing when they apply to the materials that the manufacturing needs and might evaporate before the manufacturing capability is actually created. Tariffs needs to be applied carefully and consistently to actually encourage this.
Sure, I’m just saying the article was pretty long but pretty short and declarative on the impact of tariffs. Earlier in the article for example is said there was still a factory in the US where the magnetic core material was made.
We had targeted policies under Biden to increase US production of grid components. This entailed invoking the DPA and setting aside millions for manufacturing improvements. Trump paused all that and created blanket tariffs that don’t seem like they’re designed to onshore US manufacturing of these very specific components but do increase all the material costs. This is not an easy thing to fix with dumb tariffs, and it’s really easy to make everything worse.
I’m just noting the article doesn’t have anything specific of value to say about tariff’s. This is not directed at you but rather the reporters: I can read general opinions on tariffs or political parties anywhere; I need details relevant to transformers here to not just ignore other opinions
> 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.
HVDC and UHVDC are used extensively for long distance transmission, notably for undersea cables and in China, which has made massive R&D investments in the technology in order to shift energy from West to East. Large solar, wind and hydro in the West.
However, DC does not make sense for a radial power distribution network. The article is propagating nonsense.
HVDC transmission over 100kV lines are common now. https://www.emeranl.com/maritime-link/overview
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.
I've been wondering for awhile about the economics of the AC vs DC grid thing. Historically, AC made a lot more sense because transformers are simple and relatively straightforward to make. But now we have amazing capabilities to handle enormous amounts of power with modern IGBTs and similar power-switching transistors. (A modern high-end EV motor controller, for instance, might be able to handle a megawatt of power. Not continuously, but still.) Is a DC-DC converter now more economically viable than an equivalent transformer? The former is more techincally complicated, but the latter is bulky and requires large quantities of expensive input materials like copper.
Still roughly 2x the cost and about 10x lower MTBF.
transformers are infrastructure, 100% duty cycle with a significant overload capacity that can be 3 times name plate, right there with dams and bridges, and if one developes a fault, realy bad things happen and you get a crater. There very nature makes them imensely heavy and very compact, all of the equipment used to form the parts is gargantuan, and materials to build them come in units that must be moved by house sized forklifts, consider changing a tire on such a forklift. Remember that the largest transformers travel on the heaviest rail cars, specials, these things are way heavier than anything else per ft³. Which gets us to cold,warm, or hot idle, or decomisioning, which are your choices when a huge factory has no work, hot idle means limited production, warm means some of the guys hang out and tinker with stuff, cold means, locked up,no employees but security, as decomisioning something like this has strategic considerations, or should.
The basic problem is easy to grasp, like the mess with charging cords for laptops before it, every large power transformer is a custom design. The fix would be to standardize on a much smaller number of options, and parallel them for the desired loads.
Think of it as analogous to USB-C power, on the megawatt/gigawatt scale. ;-)
People already parallel transformers. That's nothing new but it's usually undesirable because the extra ancillary equipment costs make paralleling more expensive than having a single transformer of equivalent rating if you are building it all at once.
But even fairly small standard specification distribution transformers are custom designs or very short runs. It's not economical to make the same design year after year because the relative prices of copper and core steel vary over time. A design made last year can be uneconomical to make this year because last year copper was relatively cheap so the designer used a lighter core and more copper to achieve the required efficiency. But if this year the copper price has gone up while the core steel price has gone down it would cost more to make the same design while the same specification could be achieved for a lower material cost by making a new design.
The new design is not a new type and for distribution transformers the effort required to design it is of the order of a man hour or two, far less than the difference in material costs.
For very large transformers (megavolt HVDC for instance) the situation is somewhat different and the design can take a very long time. But the opportunities for standardisation are relatively small because the quantity of units in the market is small and the manufacturers and regulators are always chasing ever greater efficiencies.
A far as specifications go there is already quite a lot of standardisation. But standards evolve over time and transformers can last for over half a century so you inevitably end up with a mixture of device types
Also, if one of your paralleled large power transformers fails you can't just buy an off the shelf replacement because no one keeps a stock of items that cost a million dollars each.
Switching to USB-C was trivial because most of the devices involved are essentially consumables with lifetimes measured in handfuls of years ad often much less so the old stuff withers away rapidly. That is not the case with large capital projects such as national electrical networks
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.
"Transformers are necessary to make the AC system work."
This isn't quite wrong but the motivation is backwards: AC is necessary to make transformers work.
1. All grids need to move energy at high voltage and low current to minimize losses.
2. This requires a mechanism to step voltages up and down for transmission.
3. In 1890 the only such mechanism was the transformer.
4. Transformers only work on AC, not DC.
Hence our legacy grid is AC.
Nowadays we have an additional mechanism: Power electronics. Power electronics work on both AC and DC, so transformers with their huge requirements for copper and steel are no longer necessary.
We need to accelerate the transition of our grid to DC because DC grids are simpler and cheaper than AC grids.
Grid-scale power electronics are also extremely niche and expensive, perhaps moreso than transformers. HVDC is used where it has a significant advantage, but ease of conversion is not one of those.
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...
It might be easier for DC transmission components to be standardized. Sure, anything with complex controls has a lot more opportunity to fail to interoperate, but DC gear can often be configured for different voltage ratios and can much more directly control how much current flows where.
Maybe the grid needs a multi-source agreement for equipment like the network industry has for optics.
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.
Also the sewer system backs up after about a week because the pumping and lift stations need power to operate.
The water system shuts down because the tanks aren't reserve supply they're pressure support.
And solar plus storage will keep you running for maybe a week if you're conservative and mostly don't use anything...which doesn't help you if it's months till replacement.
> no power for hospitals
Which have days worth of backup generator power
> refrigerated food distribution
Do you think refrigerated trucks trail big long extension leads to a socket somewhere?
Way stations still need power to accept and refrigerate shipments. Distribution isn't just on trucks - although they could act as a small stopgap that also prevents them from making deliveries while being used as storage.
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.