The 500k-ton typo: Why data center copper math doesn't add up(investinglive.com) |
The 500k-ton typo: Why data center copper math doesn't add up(investinglive.com) |
In this case the output wasn’t actually used for financial modeling. If it had been, it would have been caught immediately when someone put it into a table where they calculated the price or the supply constraints or anything else.
If news agencies needed to pay out fines for false info, you better believe they’d be checking more.
Do not install aluminum wire if you are a homeowner unless you already know enough to use antioxidant paste and also to use a torque screwdriver or torque wrench for terminations and know where to find the torque values for the wiring devices you are using. If you don’t apply the paste, the surface of the aluminum will oxidize and could catch fire due to increased resistance.
I suggest not even touching copper as a homeowner, but it’s your choice and your house.
The math they do with their assumptions is usually pretty good, and you can tell when they put in the effort, but wow, the models and assumptions are all over the place.
In reality copper is just convenient. We use it because it's easy to work with, a great conductor, and (until recently) quite affordable. But for most applications there's no reason we couldn't use something else!
For example, a 1.5mm2 copper conductor is 0.0134kg/m, which at current prices is $0.17 / meter. A 2.4mm2 aluminum conductor has the same resistance, weighs 0.0065kg/m, which at current prices is $0.0195 / meter!
Sure, aluminum is a pain to work with, but with a price premium like that there's a massive incentive to find a way to make it work.
Copper can't get too expensive simply due to power demands because people will just switch to aluminum. The power grid itself had been using it for decades, after all - some internal datacenter busbars should be doable as well.
> "Tat sounds like the ultimate catalyst for the commodities market and copper has been hitting records."
"Tat" should be "That", imo.
https://developer.nvidia.com/blog/nvidia-800-v-hvdc-architec...
Quickly doing such "back of an envelope" calculations, and calling out things that seem outlandish, could be a useful function of an AI assistant.
Even among engineering fields routine handling of diverse and messy unit systems (e.g. chemical engineering) are relatively uncommon. If you work in one of these domains, there is a practiced discipline to detect unit conversion mistakes. You can do it in your head well enough to notice when something seems off but it requires encyclopedic knowledge that the average person is unlikely to have.
A common form of this is a press release that suggests a prototype process can scale up to solve some planetary problem. In many cases you can quickly estimate that planetary scale would require some part of the upstream inputs to be orders of magnitude larger than exists or is feasible. The media doesn't notice this part and runs with the "save the planet" story.
This is the industrial chemistry version of the "in mice" press releases in medicine. It is an analogue to the Gell-Mann amnesia effect.
But bus bars generally should be protected regardless of voltage as they carry currents from high current capacity sources so even a lower voltage can be a safety concern.
Many server power supplies can take AC or DC input, with the DC input in the 300-500V range as this is comparable to the boost voltage for the AC power factor correction circuit. I just assumed most data centers using DC would be distributing around 400V within each rack.
Source: we benchmark this sort of stuff at my company and for the past year or so frontier models with a modest reasoning budget typically succeed at arithmetic problems (except for multiplication/division problems with many decimal places, which this isn't).
ChatGPT 5.2 has recently been churning through unsolved Erdös problems.
I think right now one is partially validated by a pro and the other one I know of is "ai-solved" but not verified. As in: we're the ones who can't quite keep up.
https://arxiv.org/abs/2601.07421
And the only reason they can't count Rs is that we don't show them Rs due to a performance optimization.
Those of us who don’t base our technical understandings on memes are well aware of the tooling at the disposal of all modern reasoning models gives them the capability to do such things.
Please don’t bring the culture war here.
Check it out:
https://lugsdirect.com/WhyAluminumOverCopperFAQ.htm
And you can browse that site for lugs, and they’re mostly rated for aluminum and copper. Copper-only lugs are actually rather unusual.
Sure, you can’t stick copper and aluminum wires into a wire nut, and finding terminations for smaller-gauge aluminum wire can be hard. But for larger wire, it’s really no problem.
Residential aluminum is a Really Bad Idea because DIY Dave will inevitably do something wrong - which then leads to a fire hazard. Copper is a lot more forgiving.
But a large scale datacenter, solar farm, or battery storage installation? Those will be installed and maintained by trained electricians, which means they actually know what a "torque wrench" is, and how to deal with scary words like "corrosion" and "oxidation".
Like I said: it's what's used for most of the power grid. With the right training it really isn't a big deal.
For commercial installs, it shouldn't be a problem as long as it's planned for.
That said, there is no reason we can't design better connectors that can withstand the expansion and shrinkage cycles, like spring loaded or spring cage connectors.
Most homeowners know none of the requirements of aluminum wire installation so I don’t recommend using it, oxidation is bad and can cause fires. Just pay for copper NM cable, it’s dirt cheap anyways.
FWIW I sell and run electrical work for a living. I assume crote and amluto work in the electrical industry, since they’re the only other posters in this discussion who know what they’re talking about.
The biggest reason is that aluminum oxidizes, and unlike copper, the oxide layer has high resistivity. In theory that shouldn’t be an issue in datacenters hiring expert technicians.
Aluminum bus bars(solid, often exposed) would be designed for the required power levels and installation criteria.
TIL. I thought it would be relatively expensive due to the difficulty of extracting it.
(Iron is much cheaper than I thought, too.)
The Washington Monument has an aluminum cap, which at the time was as expensive as silver. Two years later the Hall-Héroult process was invented, and as a result the price plummeted.
Aluminum has a higher resistance, which means the same diameter will get hotter than copper. Make the cable thicker and its resistance drops, which means it gets less hot.
Want more amps at the same temperature? Ohm's law still applies: just use a thicker cable.
Wire can be used for up to whatever ampacity is listed for that size wire and temperature rating in Table 310.16 (Conductor Ampacity) Copper and aluminum have separate ampacity tables because you need to use larger aluminum conductors.
Example:
#250MCM THHN copper can handle 255A in a commercial setting (75C column)
#250MCM THHN aluminum can handle 205A in a commercial setting (75C column).
NEC ampacity table: https://media.distributordatasolutions.com/ThomasAndBetts/v2...
Look at the electrical fires of the 1950’s and 1960’s as an example, and that was at household levels of current.
Aluminum is used, but everything accounts for the insane coefficient of linear expansion and other annoying properties.
Each feeder can be aluminum if you put special goop on any copper connections. Breakers accept it just fine, etc.
You should avoid it for smaller wiring, though. There's special 8000 series aluminum if you're trying to be serious with Al feeders
It's convenient, it's easy to work with, great conductivity, and cheap enough all at the sametime... Dude, I think you just explained why cropper is used instead of anything else.
Not anymore. :(
Really? In larger sizes, an equivalent ampacity aluminum cable is generally lighter and more flexible than copper. The main downside is that it’s thicker.
(Common terminations for larger wire sizes are often dual-rated for aluminum and copper. The engineering details for how to design lugs that work well for aluminum and copper were worked out long ago.)
Sure, using or not using your brain is a negligible energy difference, so if you aren't using it you really should, for energy efficiency's sake. But I don't think the claim that our brains are more energy efficient is obviously true on its own. The issue is more about induced demand from having all this external "thinking" capacity on your fingertips
It's not hard to imagine why, as the embedding vectors for terms like pounds/kilograms and feet/yards/meters are not going to be far from each other. Extreme caution is called for.
Whether talking weight or bulk a decimal place is approximately the difference between needing a wheelbarrow, a truck, a semi truck, a freight train and a ship.
Go look at the terminals on any light switch or receptacle at Home Depot, they’re all Al/Cu rated.
It’d be nice to get 1000’ of 12-2 MC cable for $500 again, but those days are gone.
Gas-law calculations were where I first encountered this bit of scariness. It was quite a while ago, and I imagine the behavior has been RLHF'ed or otherwise tweaked to be less of a problem by now. Still, worth watching out for.
Yes, but I would also expect the training data to include tons of examples of students doing unit-conversion homework, resources explaining the concept, etc. (So I would expect the embedding space to naturally include dimensions that represent some kind of metric-system-ness, because of data talking about the metric system.) And I understand the LLMs can somehow do arithmetic reasonably well (though it matters for some reason how big the numbers are, so presumably the internal logic is rather different from textbook algorithms), even without tool use.
It's better to be safe and follow specs; it's more when you're doing some compound splice where it makes sense. I figure it'll make more people feel easy about it if there's a preventative measure
> difference between needing 26666666.667 and 266666666.667 <units> of <widget> is pretty meaningful
To be fair, that’s why we’d use 2.6666666667e7 and 2.66666666667e8, which makes it easier to think about orders of magnitude. Processes, tools and methods must be adapted to reduce the risk of making a mistake.
Engineers prefer (wait for it) "Engineering Notation": 26.67e6 and 266.7e6.
Feasibility and geological implications are left as exercises for the reader.
Regardless, I suspect a more cost-effective fix would be to redefine the meter to be a couple "legacy" millimeters longer.
So, this is rather complex because you can turn AI energy usage to nearly zero when not in use. Humans have this problem of needing to consume a large amount of resources for 18-24 years with very little useful output during that time, and have to be kept running 24/7 otherwise you lose your investment. And even then there is a lot of risk they are going to be gibbering idiots and represent a net loss of your resource expenditure.
For this I have a modern Modest Proposal they we use young children as feed stock for biofuel generation before they become a resource sink. Not only do you save the child from a life of being a wage slave, you can now power your AI data center. I propose we call this the Matrix Efficiency Saving System (MESS).
Also, while a body itself uses only 100W, a normal urban lifestyle uses a few thousand watts for heat, light, cooking, and transportation.
Add to that the tier-n dependencies this urban lifestyle has—massive supply chains sprawling across the planet, for example involving thousands upon thousands of people and goods involved in making your morning coffee happen.
Obviously not equal to a human brain, but my GPU takes about 150W and can draw an image in a minute that would take me forever to replicate.
1: https://www.nature.com/articles/s41598-024-54271-x?fromPaywa...
I agree with your point about induced demand. The “win” wouldn’t be looking at a single press release with already-suspect numbers, but rather looking at essentially all press releases of note, a task not generally valuable enough to devote people towards.
That being said, we normally consider it progress when we can use mechanical or electrical energy to replace or augment human work.
Old aluminum wires in your walls were designed for a time when you lit your home with 100 watt incandescent lamps rather than 12 watt LEDs.
The quantity and (edit: aggregate) power draw of modern appliances is far greater now than 60 years ago, so the overall load on the old wires is much higher.
Here's a article that claims that refrigerator energy efficiency has improved dramatically from 1972 to 2012.
https://appliance-standards.org/blog/how-your-refrigerator-h...
I'd bet that modern TVs are more efficient that CRT televisions. Do most people even have desktop computers anymore, or have they mostly been replaced by laptops, tables, and phones? I'd be interested to see the efficiency numbers for electric clothes dryers over time. I wouldn't be surprised if they are also slightly more efficient than older models, even if they are still using resistance heating. Due to smarter electronics that automatically turn the unit off after the clothes are dry (air humidity sensor). I think electric ranges, dish washers, toasters and coffee machines have been ubiquitous since the 1960s (but are probably about the same energy-consumption wise). Air conditioning units are one thing that I'd believe are much more common today than in the 1970s and 1980s. Household sizes are also smaller, so less electricity used for electric water heaters, and the oven, etc.. Electric vehicles are an up and coming user of electricity. What other appliances are likely to be using more now than before?
I can’t think of a single appliance from 1970 that consumes less energy than its modern equivalent. Anything with a pump or fan is more efficient and so is lighting. LCD TVs use less energy than CRTs.
I also can’t think of an appliance that has become common in households that draws more than 100 watts of continuous load since the 1970 aside from just ‘computers’. An ancient 500W 80% efficiency PSU at max load only has 5.2A of current at 120V single-phase.
If you convert your natural gas furnace to a heat pump, you will use more electricity but excluding that and NG to electric HPWHs leaves only more efficient equipment.
For example does it factor in the 18-24 years needed to train a human and the energy used for that?
The history is quite interesting and well worth checking out.
I can't recommend a book on the subject, but I do heartily recommend "Longitude", which is about the challenges of inventing the first maritime chronometers for the purpose of accurately measuring longitude.
It's not the most aesthetic one, but it was at the time the most able to be measured.
There is, of course, no more need to standardize on a specific brand or style of cigarette than on a specific depth of Olympic-sized pool.
And that's ignoring sources like food from agriculture, including the food we feed our food.
To be fair, AI servers also use a lot more energy than their raw power demand if we use the same metrics. But after accounting for everything, an American and an 8xH100 server might end up in about the same ballpark
Which is not meant as an argument for replacing Americans with AI servers, but it puts AI power demand into context
Standard small-house service used to be 60A, sometimes as few as 4 circuits! It's now 100A minimum by code, with 200A common.
Ovens/ranges have gone from 30A to 50A (dedicated) circuits by code. Microwaves also require dedicated circuits now. Gaming computers with big GPUs are common. Air fryers and electric pressure cookers are newly-common countertop appliances. People definitely use resistive electric space heaters more now (very cheap, much safer than the older options). And there's a trend away from gas and to electric ranges and water heaters. Heat pumps are also increasingly common. You mentioned air conditioners and EV chargers. Kitchens and bathrooms are now required to have dedicated (and GFCI) circuits. Household sizes are smaller, but houses are larger.
So I guess I'd say that, properly expanded, individual circuits should carry less current than they used to. But very often, appliances (AC, microwave, gaming rig, air fryers), are just "plugged in" to an unexpanded system, with varying results.
If you're lucky, they pop a breaker and you call an electrician. If you're not lucky, they push the power draw into uncomfortable zones, esp for Al wire.
Is there a good way to quantify this?
I don't track that market (not a gamer), but it seemed substantial enough that I was aware of it. I do travel in geeky circles though.
Also, plasma TVs were big for a decade or so, and they run hotter than the CRTs that preceded them, or the LCDs/etc of today.
In a renovated house, you won't have aluminum wire at all, so these concerns are null.
My original statement should be qualified. Since we were talking about aluminum wire it's relevant -- an updated house will have new (copper) circuits that can handle all this stuff. An NON updated house might have Al wire and be overloaded in a more severe way than it was in the 60s.
But FWIW, new >100W appliances:
- microwaves (1200+W)
- air fryers (1500W)
- electric pressure cookers
- rice cookers (mine claims 610W on the plate)
- stand mixers (old: 80W, new: 475W)
- desktop computers (esp gaming rigs)
- resistive space heaters (1500W)
- *bigger* TVs (compare 72" LCD to 19" CRT?)
- air purifiers (mine clocks 175W on high)
- towel warmers? :)
- and the ubiquity of 10-20W small stuff has of course exploded, and it all adds upPerhaps, but none of them are continuous load, which absolutely matters.
Rice cookers, microwave, stand mixers, air fryers, pressure cookers, etc are all short duration usage, not continuous load. If homeowners decide not to add dedicated kitchen circuits and instead use a 120V 12A load on a 120V 15A shared circuit and trip the overcurrent protection, that’s their own fault.
These loads don’t really matter in the way a heat pump, air conditioner, furnace fan, or water heater does, it’s a bunch of random kitchen appliances that you won’t be using simultaneously. Your utility does not even take the full non-continuous load into account when calculating the kVA demand of your electrical service. IIRC a random convenience duplex receptacle for non-continuous loads only adds like 180 VA (this is 1.5A at 120V with a power factor of 1) to the demand calculation.
You are correct in a technical sense that people have more devices they plug into a wall, but most of the power consumed by a home is to devices that are hardwired in, aka continuous loads, not cord and plug connected appliances.
The continuous load of a home should be lower than ever without electrifying heat. Every continuous load (which are almost exclusively motors and lighting) in a home is more efficient now than in the past due to variable frequency drives and electrically commutated motors.
Varying high loads are more significant than a continuous medium load in terms of the effects on wiring junctions.