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Cake day: March 22nd, 2026

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  • I think you have to look at the actual orders of magnitude difference in raising the temperature of water versus air. The Arizona story you linked is about a study that found up to +4°F (+2.2°C) temperatures in air.

    The same amount of heat, spread across the same volume of water moving at the same speeds, would only raise that water by 1/830 as much, for a +0.0048°F (+0.0027°C) 1/3300 as much, for a +0.0012°F/+0.00067°C temperature change across the same area/volume.

    (I got to 830 by taking the specific heat of dry air of approx 1 J/g K at room temperature and regular atmospheric pressure and 1.22 kg/m^3, versus water’s 4.184 J/g K and 1000 kg/m^3).

    (Edit: I fucked my math. Water has approximately 3300 times the heat capacity as air, per unit volume, and I just looked it up directly).

    The higher conductivity of water might be offset by the higher convection potential of air (because air responds to temperature changes with differences in density/pressure, which creates wind in itself), so that the heat will spread through either medium relatively quickly and therefore dissipate very quickly with distance to the source.

    I just don’t see a world where a data center raises the water by even 1°C, even locally.




  • This page says the ocean is about 352,670,000,000,000,000,000 gallons, which is about 1.3 x 10^21 liters, and each liter is a kg of water (yeah, yeah, the dissolved salt adds some mass but I don’t think it adds sufficient thermal mass to make a difference). It takes 4.184 kilojoules to raise 1kg of liquid water 1°C, and 1 joule is 2.778 x 10^-4 wh.

    So that’s 1.55 x 10^18 watt hours, or 1,550,000 TWh.

    Global electricity consumption is about 30,000 TWh per year, so if you use the entire world’s electricity consumption for 51 years you’d raise the oceans’ temperature by 1°C.

    Or if you take global data center power capacity of about 125 GW, and ran them at full power 24/7, you’d be producing about 10.8 TWh per day or 3944 TWh per year. It’d take about 393 years of the world’s data centers to raise the ocean by 1°C.

    Just goes to show that much more of the energy heating up our world and our oceans is coming from the sun heating up the planet and the planet failing to radiate it out past our greenhouse blanket, not from the actual heating of our atmosphere from our own energy sources.


  • GFCI doesn’t protect against arcs, so AFCI would be necessary to protect against arcing causing fires.

    The danger with outdoor outlets is short circuiting (like when water drips onto a live wire), so GFCI is almost always required of outdoor outlets. Generally, outdoor outlets also require covers that keep the receptacle dry, at least when not in use (and more modern code generally requires it have an “in-use” cover that can stay on even when something is plugged in).

    But having GFCI isn’t the same as AFCI, so arc fires can still theoretically happen.



  • Taste: it’s actually really hard to taste just as good as normal meat, as meat is not only meat but also fat, tissue and blood.

    One thing I’d push back on is the idea that meat has one single flavor. It’s entirely possible that we’ll be able to replicate many different types of sausages and meatballs and ground meats, things like imitation crab or meatloaf or chicken nuggets, while still struggling to mimic whole muscle cuts. Or it may be easy to mimic certain types of flavors like meat-based soups and sauces, or poached/braised meats, while not quite getting there on grilled or roasted meats.

    Meanwhile, I can also see a world where lab-grown meat is cost competitive with more expensive meats, like beef or lamb or lobster, while not being able to compete with cheaper meats like chicken.

    It doesn’t have to be all or nothing substitution. Sometimes imperfect substitutes can partially replace something and reduce overall demand while the original item still remains available in smaller volumes.






  • But fundamentally there is less energy storage in a charged sodium atom than a charged lithium atom so it seems sodium batteries must always be bigger and heavier than equivalent-capacity lithium batteries.

    Well the battery chemistry will always include much more than just the loose charge carrier of Na+ or Li+ or whatever cation floating around. It’s always a suitable cathode material made from other elements, too. Lithium ion batteries in cars today have cathodes mostly of high performance lithium nickel manganese cobalt oxides (NMC) or cheaper/more stable lithium iron phosphate (LFP).

    The dominant sodium ion chemistry hitting mass production now uses Prussian Blue Analogues for the cathode (made from a 3d matrix out of sodium, plus a metal like iron/manganese/nickel, plus cyanide made from carbon and nitrogen).

    Plus even separately from the raw chemistry of the battery, built in mechanisms for durability or longevity or charge cycles or thermal management or safety or other material properties may change the overall weight of the battery for any particular performance characteristics.

    In the end, the performance of the entire battery is what matters, and lithium’s head start in less weight per cation may one day be overcome if the overall materials involved can be lighter in some as-yet commercialized sodium ion chemistry.





  • now both Hyundai and Kia have stopped selling EV models last year solely in the US

    They’re basically one company and they stopped importing EVs. They still build and sell plenty of new EVs in the U.S., made in their plants in the state of Georgia. They’re also currently expanding capacity at their plants, in the hopes of catching more of the growing electric SUV market.

    So they no longer sell the top of the line trim level of the Kia EV6, or the Hyundai Ioniq 6, but they’re still building and selling very similar models on the same platform. The Kia EV6 still exists in the lower trim levels, and the Ioniq 6N and the Ioniq 5 and 5N, and their smaller EVs (Kia Niro, Hyundai Kona) are still available, too. Both brands launched their 3-row electric SUVs in the US, too (Hyundai Ioniq 9, Kia EV9).

    A lot of companies are slowing down their EV rollouts, but I wouldn’t say that Hyundai/Kia is the best example of that.


  • Average new car price has gone up a lot because the average new car has been purchased by rich people who demand high performance and luxury features. And rich people have been doing great the last 50 years, so the top of the market has totally run away with high prices.

    If you actually dig into specific models and what they go for, you see that the most basic cars have only gone up slightly in price, but are also much higher performing (0-60 times, quarter mile times, braking distance), more efficient (better highway/city gas mileage), more reliable (more miles/years to failure), and have a lot more standard features that used to be expensive add-ons (automatic transmissions, power windows/locks, power steering), and are generally better constructed (smaller panel gaps, better sound proofing/vibrations), and much, much safer by pretty much every measure.

    Today’s cars, even the cheapest ones, are much better than the cars from the 90’s, much less the cars from the 70’s (5-digit odometers because getting past 100,000 miles wasn’t necessarily expected, bodies that rusted within a decade of normal use).

    So if a first generation Honda Civic in 1974 cost $3000 in 1974 dollars (inflation adjusted to $21,000 today), we should compare what that car was, compared to what a Honda Civic is today (starting at around $25,000 for the barebones model, $30,000 for a few nicer features). Compare torque/horsepower specs, actual performance at 0-60/quarter mile, gas mileage, all of that. I’m not entirely convinced that the people of 1974 were getting a better bargain on their cars than today’s new economy car buyer.

    I hate that cars have gotten so big, and that the SUV is basically the American default at this point. But I don’t think that car prices have actually gone up that high in the 30 years I’ve been driving. And cars from before I was driving just…sucked.


  • It would still depend on a non-renewable resource that needs to be mined

    One thing to point out is the energy density in nuclear fuel, even before reprocessing, is higher than all the energy that will pass through the same amount of lithium processed into rechargeable batteries, over the entire life cycle of that battery. A typical 1GW plant consumes an average of 70 kg of fuel per day, at a 90% capacity rate. So that’s 24 hours x 90% x 1000000 kW, divided by 70 kg, for about 300,000 kWh per kg of fuel.

    Meanwhile, LFP batteries are about 10% lithium and have 150 Wh per kg of battery weight. Let’s say the battery can get through 10,000 charging cycles before recycling. That’s 15,000 kWh per kg of lithium.

    Obviously lithium can be recycled and uranium fuel can be reprocessed. We can also compare the very inefficient extraction of either element (uranium or lithium) from the actual natural ore pulled out of the ground. And the very involved manufacturing processes of turning that ore into useful fuel or batteries.

    But either way, the overhead of mining physical stuff to support the supply chains of things that get used up, even reusable/recyclable durable goods, will always be there. Uranium genuinely is special in its energy density and requires closer examination of the calculations.


  • Yeah, one of the issues I’ve read about happening for concrete failures was that some construction crews are under enormous pressure to salvage concrete that had been mixed too early, or delayed in pouring, or whatever, and where the concrete pouring characteristics cause issues (or crews add unauthorized water or things to slow down curing and then alter the characteristics of the poured concrete without the engineers’ awareness).

    It’s wildly counterintuitive to those of us who don’t work in the space.