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Cake day: October 12th, 2024

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  • Lithium grid batteries are a non-issue for safety, in practice. They’re LFP (which is really forgiving heatwise, as lithium batteries go) and adding a ton of passive cooling isn’t a big deal since weight isn’t a problem when it’s stationary. And sodium-ion will only be better in this regard.

    Recycling is overblown as a problem. Like any industry, recycling needs scale to be economical, and every new tech isn’t recycled at scale until 1) it’s produced at scale, and 2) that generation produced at scale reaches EOL and needs to be recycled.

    In practice, recycling lithium batteries is a non-issue because a lithium battery contains an entire battery’s worth of lithium (it’s ~10%+ lithium - and that lithium is a liquid that, when drained out, is >99% lithium!), whereas lithium brine is like 0.1% lithium. It’s not hard to recycle most of the battery, and the other parts will only be learned after we have mountains of free dead batteries to practice on, not before.




  • Solar was rapidly getting cheaper, hydrogen isn’t. Sooner or later, batteries will be more energy-dense than hydrogen - I don’t think you understand just how dogshit hydrogen truly is.

    Hydrogen is, IIRC, ~30% efficient roundtrip (multiply the efficiency of the electrolyser (70%?) with the efficiency of the fuel cell (50%?)), where batteries are 90%. And batteries are waaay cheaper per cycle. That’s why BEVs are selling like hotcakes whereas surplus hydrogen cars from failed hydrogen car initiatives can’t be sold (that’s not entirely true - they’re being bought up and converted into BEVs).

    So batteries are cheaper, their power source is cheaper (because they’re ~3x the efficiency of hydrogen - and BTW that basically won’t change due to thermodynamics, hydrogen is just fundamentally rather inefficient), and you need a ridiculously absurdly expensive pressurized pumping system just to refill your hydrogen tank (which BTW has huge problems of its own because when you pump hydrogen into an empty tank it expands, and when hydrogen or helium expands it heats up, which then needs cooling which takes a bunch of power and engineering work), what’s the advantage of hydrogen?

    Well theoretically hydrogen is more energy-dense. Except there are two types of “energy density” (the term is often used loosely/wrong) - there’s power per weight (specific energy), and there’s power per volume (energy density). And hydrogen is literally the least dense substance in the universe, that’s why we filled airships with it, and it’s why we need pressurised tanks in hydrogen cars. Pressurizing the tanks helps, but not by much. It still sucks unless you’re using it as rocket fuel (which cares a lot about weight, not so much for volume)

    So, hydrogen needs pressurized tanks. Pressurised tanks weigh a lot, and they weigh more the smaller the tank! (the weight overhead follows the cube-square law). And car fuel tanks are much smaller than rockets.

    What’s worse is that unlike fuel tanks, hydrogen tanks need to be cylindrical (or theoretically spherical) to efficiently contain the pressure. Which means they’re a pain in the ass to fit onto a car, because they can’t be flat. They’re in practice way worse than batteries, volumetrically, because batteries can be low and flat on the bottom of the car, in the middle between the axles for a nice clean centre of gravity. You can sort of flatten the hydrogen tank by having two cylinders side by side, but that’s inefficient and adds a ton of weight, which undercuts the point of using hydrogen in the first place.

    Hydrogen refills quickly… But so do batteries nowadays. And of course if you really care them you can just make batteries swappable (check out Janus trucks, they have swappable batteries that take less than 5 minutes to swap with a forklift, and they’re actually commercially used in the real world on public roads, unlike hydrogen trucks).

    By the way, you know how BEVs can literally be charged with a $20 power cord plugged into a standard wall outlet? Guess how much a hydrogen refuelling station costs (keep in mind the entire thing has to be pressurised). Are you ready?

    $3million.

    LOL

    (Even a DC fast-charger is sub-$100k (might be closer to $10k I forget)

    All that to pay more than petrol costs (even post-Hormuz, hydrogen is still 10x more expensive IIRC). But still, if you ignore the practical range limitations, you still have more range than a BEV though right?

    Yes, you do. I forget the numbers but it’s not that much better (like 20% or 30% maybe?) and absolutely not worth almost literally everything else being worse than batteries.

    But I forgot the worst part of hydrogen: it can’t be produced by unfirmed solar panels. It’s not a flexible chemical process, so realistically you need batteries to firm the solar panels while they electrolyze. Chuck that onto the giant “technical breakthroughs required to make hydrogen fuel a thing” pile, I suppose.

    We’ll still need green hydrogen as a chemical input, it just doesn’t make sense as a fuel.

    Seriously, why adopt the world’s most explosively flammable gas that’s also a chemical Houdini when you could just… Not handle fluid transfers in the first place and just transfer electricity normally, with a wire?

    Why would anyone consider mass-adopting a 30%-efficient battery?

    Hydrogen electrolysis currently requires an iridium catalyst for practical long-term durable efficient electrolysis, and might always require one. Iridium is stupidly expensive and a major reason why hydrogen can’t currently scale. Chuck it onto the “technical breakthroughs required” pile, I suppose.

    I do think hydrogen-based energy has a future, funnily enough - I have high hopes for the TABQ “proton batteries” (AKA hydrogen-ion, which is like lithium-ion but a positive hydrogen ion is literally just a proton. It should be theoretically more efficient - hydrogen is lighter than lithium, after all). It’s a cool tech, if very new, and I hope it succeeds. It’s just a normal battery, one made from an organic molecule (TABQ) with no need for rare materials.

    I used to be on the hydrogen hype train myself, but it took me an embarassingly long while to realise that hydrogen was motivated by hype and wrong thinking more than any technical merit. Especially said thinking by chemical and car companies. Hydrogen is a fuel, like hydrocarbons, and if you can’t imagine a world without fuel - a world where you don’t take your car to the fuel station and fill it up - then hydrogen is the only alternative. BEVs charge slower because they don’t need to charge quickly at home - in other words, they’re different and we have to think of them differently. Hydrogen is in basically every way the type of round-peg square-hole thinking that’s preventing adaptation to climate change; it’s this absolute turd that people are nonetheless actually considering adopting.

    Seriously, why would you want to reinvent fuels? To paraphrase Technology Connections, the problem with fuel is that you have to literally light it on fire and replace it every time you use it. CATL’s latest Sodium-ion batteries claim a cycle-life of 15000 cycles, whereas hydrogen fuel has a cycle life of 1. Battery cycle life is only getting better, hydrogen will always be single-use, just like diesel.

    We have commercially-viable battery-electric planes (namely the Heart X1, a 30-seat regional airliner - not just a wimpy Cessna replacement, although we have an electric Cessna knockoff too) before we have commercially viable hydrogen planes. Because batteries let airlines save money on fuel. If there’s one place where hydrogen’s better energy-weight ratio should dominate, it’s aerospace, but hydrogen has nothing.

    I guess what I’m saying is: if you were wrong and hydrogen is indeed a pipedream, what would look different to our current situation?


  • Which is stupid and insanely expensive, since methane itself is an insanely potent greenhouse gas and methane has plenty of fugitive emissions.but, back up a second: isn’t the main reason for banking so much methane in the winter… heating? Because we can easily 10x the efficiency and 100x the cost - efficiency, by skipping the hydrogen - methane crap and storing heat directly.

    See, you can store heat trivially in insulated thermal mass. “Thermal mass” is basically just mass, I.e. dirt-cheap materials such as rocks or dirt. You can skip a whole raft of fluid-handling stuff (methane and hydrogen being fluids, and fluids requiring pipes, pumps, leakage handling, inspections etc) by just using electricity from summer solar to resistively heat a 20m-diameter cylinder full of rocks wrapped in 1m of insulation, and when you need heat in winter you can just run air through the vents to extract that heat. It’s based on 1950s technology (probably older tbh) and most of the materials are literally dirt-cheap. Hook it up to district heating and you have an effectively infinite battery to handle your winter heating needs, based on informed summer renewables costs. Sand, insulation, a big cylinder (probably the most expensive part), resistive heating, an air vent. None of it is expensive (except the land, but those 300sqm can be located underground if it helps) and it’ll last for a century because there’s nothing that can even break.

    It’s basically just a bunch of sand wrapped in an electric blanket (and an actual blanket). It’s dead simple.

    Compare all that to a hydrogen electrolyser on a river, with a chemical plant to transform the hydrogen into methane (with carbon from where, exactly?) then a pipe or tanker or truck to transfer the methane to a big methane storage cavern, which is then piped to an individual furnace to burn. That’s a Rube Goldberg machine.


  • It’s a mix, not a battle. Kill nuclear and you pretty much kill decarbonisation.

    We need some nuance here. In e.g. South Korea, I agree. Nuclear is needed.

    But here in Australia, nuclear is unfathomably stupid. Not only do we not need nuclear, but it’d take decades to build (because we haven’t built one before so we’d have to first write the laws, then build the supply chain, train the workforce, design a nuclear plant to build (again: we haven’t built one on this continent before, we can’t just assume a design from a different climate will work) and then build it (with a construction workforce we might have to import or train). All up, it’ll take longer than building 100% renewables.

    Which is exactly why our far right-wing lunatics are advocating it as an alternative to renewables (note that I said alternative, not complement), and to build more coal plants in the mean time.

    The whole battery discussion is similarly stupid. In Australia, you don’t need storage for more than a week. And within that week, renewables rarely reach less than 70% average (note that “fucktons of energy on Monday and fuck all on Tues through Sunday” can still add up to 70% of an average week’s energy, though), and never reaches 50%. What that means is that we will need at most 2x the renewables and half a week’s worth of batteries. And of course realistically it means we only need ~1.43x the renewables (it’s not always worth building to meet every possible once-in-a-blue-moon outage when we can pay people (especially commercial customers) to take their demand offline) and to diversify our energy sources (read: offshore wind and onshore wind peak at dusk and nighttime).

    More importantly, sooner or later the combination of renewables and batteries will make the marginal Watt-hour from a battery cheaper than the marginal Watt-hour from burning a unit of gas in a turbine. Especially when chasing reliability will inevitably produce cheap surplus energy to store - e.g. suppose solar has collapsed the market for midday power but a new solar farm might still be profitable just by selling more power from 3PM onwards and before 9AM in the morning. That solar farm still wants a customer for its otherwise-wasted midday power and will take basically any price above zero, which means the cost of battery power is effectively just the cost of the battery itself since the midday solar is essentially free and infinite.

    This is already in the process of happening (again, in Australia) and gas turbines are dying.

    And seriously, fuck nuclear (in Australia). It’s main advocates here deny global warming is real (or at least deny that humans caused it), reject Net Zero by 2050 as radical and unaffordable, and want to block wind/solar farms and transmission lines as much as they can get away with. They are fucking clowns.

    To be fair, I don’t think they actually want to build nuclear, they’re just pushing it as a bad-faith ploy to kill renewables, and if they succeed will immediately pivot to “nuclear unsafe, we should build coal plants instead”. They already need a stopgap since our current coal plants will shut down ~2035 and there’s no way we’ll have nuclear up by then, so if not renewables then we’ll need to build coal or gas as a stopgap (and there’s no way that those coal/gas plants will be profitable if they’re shut down 10 years after construction due to the nuclear plant being ready, so they’ll be even more expensive in that context).

    Seriously, the Liberal Party (a conservative party), the National party (rural party, also conservative) and Pauline Hanson’s One Nation Party (PHON is like Nigel Farage’s party I think, BTW I’m assuming you’re British because your instance is feddit.uk) are absolute clowns on climate policy (and nuclear). Although it doesn’t help that the Libs have completely collapsed to the point that One Nation is looking to eat their lunch in the next election, so they’re currently trying to out-One Nation One Nation, which they’re obviously failing because they can never be as One Nation as One Nation so voters will just vote for the genuine article. And One Nation’s policies (assuming they have any) are unfettered by any concern about actually getting into power and implementing them, with Pauline Hanson (and her fellow party members) will respond to questions about their policy by trying to pick a fight and throwing names (a comparison to Trump isn’t too far off).

    Anyway, I don’t know whether nuclear would be a good idea in UK, and it might well be, but it’s stupid in Australia and so is basically everyone who advocates for it (in Australia) at this point.






  • On the one hand: Yes, go to the ballot and vote blue. Even if they’re 99% Hitler. If you think you have “nothing to lose”, go look at Syria or Russia. ‘The worst the Republicans could do’ is worse than you can imagine.

    On the other hand: Have you ever heard of the ultimatum game? Imagine you and a friend are offered $100, and your friend offers you a split of $X. You can either accept the $X, or reject it and you both get nothing. You might think you should accept the $X no matter how low, but if the scenario happens again and you have rejected low values last time, your friend will be more likely to offer you a fair X. Otherwise, if your friend’s a bastard (and he is), he’ll offer you $1.

    Anyway, in 2020 the X offered was a Biden, and in 2024 the X offered was a Kamala. If every Leftist votes for Biden/Kamala/Next, then the DNC will keep offering the same dogshit or even shift right because 1) they want to grab more centrist voters (who won’t vote for a more progressive candidate), and 2) they won’t lose any leftist voters so why not. And then when the right-shifted candidate loses they’ll blame it on “leftists didn’t vote enough” anyway, in spite of the statistics saying otherwise.

    So in other words: If you’re willing to vote for a 99% Hitler, don’t be surprised if you’re offered a 99% Hitler. Unless you’re expecting the DNC to be extremely principled, anti-corruption, and spineful?

    “Vote blue no matter who” isn’t a solution; it’s forfeiting democracy (if you follow it, you literally don’t get to choose not to vote blue) in pursuit of… not letting Republicans in. Great! The Dems reliably prevented Trump from being re-elected, right? No, he trod water in the status quo but didn’t actually fix the core problems, so Trump’s “vote me in and I’ll burn down the system” still resonated with voters. But hey, at least Biden prosecuted Trump and all the criminals who he enabled to flagrantly break the law and rewrite it to their benefit? Not really, no.

    “Vote Blue No Matter Who” is a travesty which can be at best justified as a strategy of lesser evil - but still evil. If it doesn’t have an expiry date then you’ve already abolished democracy, and that’s fucking horrifying, even if it’s the correct strategy.