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Wind turbines definitely can, if for no other reason than that they are required to be able to demonstrate that they can survive a sudden grid drop without tearing themselves apart. I don't know why you would ever do this on purpose while its not idling/braked and you're not testing this particular emergency situation.
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May 1, 2023 00:09
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spf3million posted:This feels like a very dumb question but can solar panels be "shut off" if their power isn't needed? Like could there be a remote relay that just opens a breaker to stop their contribution to the grid? Same for wind turbines? My very crude understanding is that solar panels left in an open circuit do nothing, you need to actually place a load on them to extract power. This is what the inverter does, and a decent inverter will place an appropriate load to extract the maximum amount of power available for the amount of sunlight falling on the panel.
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May 1, 2023 00:16
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Yes, the solar system can throttle from 0% to whatever % sunlight you have available, and it's effectively instantaneous.
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May 1, 2023 00:22
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We have a lot of rooftop solar here, and some plans that feed energy back into the grid are setup so the panels are shutoff instantly when it would be dangerous to feed energy into the grid.
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May 1, 2023 07:33
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FWIW, the NRC has decided that fusion power plants will be regulated like particle accelerators, and not like fission plants: https://www.fusionindustryassociation.org/post/nrc-decision-separates-fusion-energy-regulation-from-nuclear-fission
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May 3, 2023 15:18
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Phanatic posted:FWIW, the NRC has decided that fusion power plants will be regulated like particle accelerators, and not like fission plants:
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May 3, 2023 15:57
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drat. Maybe I shouldn’t have bought that old firehouse.
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May 3, 2023 16:26
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cat botherer posted:They'll still come down pretty hard on any unlicensed particle accelerators, though. Don't tell them but I'm still running a CRT monitor 
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May 3, 2023 16:32
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Phanatic posted:drat. Maybe I shouldn’t have bought that old firehouse. that's a job for the EPA
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May 3, 2023 16:56
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KillHour posted:Don't tell them but I'm still running a CRT monitor are you in the UK?
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May 3, 2023 17:50
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Electric Wrigglies posted:are you in the UK? No? Why?
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May 3, 2023 18:21
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KillHour posted:Don't tell them but I'm still running a CRT monitor drat, so you can't use it in Florida?
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May 4, 2023 03:37
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Jows posted:drat, so you can't use it in Florida? I was informed that wokeness and Biden is the reason that conduit and unistrut is so expensive. E. SpeedFreek fucked around with this message at 22:58 on May 6, 2023 |
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May 4, 2023 04:18
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Jows posted:drat, so you can't use it in Florida? 
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May 4, 2023 07:20
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KillHour posted:No? Why? I don't know if they still do but the UK was famous for having requiring a TV license to watch the public broadcaster. Obviously in the days of ariels, it was a bit of an honour system but vans did drive around trying to identify is someone was using a TV to watch the public broadcaster without a license.
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May 4, 2023 08:01
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A license is still required. Even if you don't watch the BBC the TV license people will spam you with leaflets trying to get paid.
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May 4, 2023 08:29
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Electric Wrigglies posted:t vans did drive around trying to identify is someone was using a TV to watch the public broadcaster without a license. That's disputed. I mean, there were vans that the BBC claimed were TV detector vans. But they were probably just propaganda. https://arstechnica.com/tech-policy/2016/08/bbc-tv-licence-vans-wi-fi-snooping-analysis/?comments=1&comments-page=1
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May 11, 2023 15:33
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TV detector vans are plausible based on the same principle as radar detector detectors, which exist and are used by police in areas where radar detectors are illegal. Superheterodyne receivers generate an intermediate frequency signal which can be detected and if you know the design of the receiver that can be used to determine what frequency it's tuned to. In the modern era with better shielding, lower power equipment, and digital multiplexing the technique still works in theory but is a lot less useful in practice. A much simpler approach that still works today would be to just drive around at night and watch the level of light cast by a TV on the windows. If there's a known commercial break coming up where the screen's going to go black you could reliably tell who's watching that channel live by seeing which windows dimmed. Less effective of course in the world of DVRs and lots of channels to choose from, but still potentially effective during major live events.
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May 11, 2023 16:36
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Remember the Fusion company Helion? https://www.geekwire.com/2023/microsoft-and-helion-want-to-build-the-worlds-first-fusion-plant-and-seize-energys-holy-grail/ Apparently they made a deal with Microsoft to deliver a functional powerplant worth 50MW by 2028. You may think that it's some scam, where Microsoft paid in advance, but it's actually the opposite. They wont pay any money until the electricity flows and Helion has to pay a fine if they don't meet the deadline. I know that many people are sceptical of Helion, their approach and their tight timeline, but I think they must feel quite hopeful for their big test reactor in 2024, otherwise they wouldn't really gain anything from signing that deal. So either their confidence is genuine, or they intentionally set themselves up to pay massive fees for no gain, just to make other investors more confident. Either way, it seems like a win-win deal for Microsoft. cant cook creole bream fucked around with this message at 16:53 on May 11, 2023 |
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May 11, 2023 16:51
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cant cook creole bream posted:they intentionally set themselves up to pay massive fees for no gain, just to make other investors more confident. I have bad news about investor behavior under capitalism.
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May 11, 2023 17:13
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Phanatic posted:That's disputed. I agree with you. My dad from that vintage who is a retired radio technician always said that if you looked, he expected there to be a hand crank with no wires on the inside of the van for a guy to rotate the dish to make it look like it was functional direction finding equipment. He tells the story from his time in the navy, a Canadian destroyer mounted a guy in a trash bin on a mast so that when a Soviet helicopter flew past, the lid would spring up and "lock on" to the helicopter (without any emissions, of course). The helicopters kept visiting the destroyer and the trashcan would reliably spring up and track the helicopters, seemingly a lot of interest in the new equipment that was being used by the Canadian ship. It was a joke that many an analyst wound up in Siberia for telling their boss it was just a trash can.
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May 11, 2023 17:25
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cant cook creole bream posted:Remember the Fusion company Helion? I'm of course hopeful, but let's just say I'll believe it when I see it. There'd better be a lot more to their system than what they've disclosed to the public. I'm not a fan of this youtuber (I roll my eyes when he tries to 'joke') but the issues he points out are pretty fundamental: https://www.youtube.com/watch?v=3vUPhsFoniw
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May 11, 2023 18:08
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What is the theoretical advantage Helion is offering over Takomak or Stellerators or Big Lasers?
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May 11, 2023 19:29
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Helion's design (supposedly) directly generates electricity, while more traditional designs are more of a "hot plasma transfers heat and boils water" approach.
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May 11, 2023 20:13
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Family Values posted:I'm of course hopeful, but let's just say I'll believe it when I see it. There'd better be a lot more to their system than what they've disclosed to the public. I saw that video a while ago. That guy didn't really put a lot of effort into into be quite honest. He mentioned some stuff which was disputed long before and presented mechanical hurdles like huge impassable baricades as if nobody before him had ever thought about those. Raenir Salazar posted:What is the theoretical advantage Helion is offering over Takomak or Stellerators or Big Lasers? There's actually a several ones (assuming any of it works out, of course.) The biggest one ist the fuel. Most attempts at fusion are based on the combination of the hydrogen isotopes Deuterium (D) and Tritium (T). While D absolutely plentyful and quite easy to produce from seawater, T doesn't really exists and decays after 12 years. The only supply is from radiation in cooling water for fission plants. And the production is way below what ITER alone would need. Helion's fuel cycle effectively only uses Deuterium as input. It produces and uses Helium3 (aka Helion) as an intermediate step. Another big advantage is that pulsed generation can be scaled. If the energy grid is full, you can chose not to add further reactions on a whim, while a tokamak could only be useful other longer contiuous operation, which are hard to maintain anyway. This also means that you can clean the used fuel from the barrel after each reaction, which seems dubiously possible in tokamaks. And then there is the big difference between netronic and aneutronic reactions: D T reaction produce almost all of their energy as fast neutrons (i.e. nuclear radiation .) While those are on another power level then the ones from a fission plant, you shouldn't stand near that. The only way to extract that energy is to do the same thing as yfission plants do. Heating and boiling water to make turbines run. This other reaction D+He3 releases the energy as a fast proton. The cool thing about that? Protons have a magnetic charge. The same magnets, which squeeze the hydrogen can steal the speed of those protons and directly convert that to electricity, no water heating required! That last part sounds a bit out there, but that concept has actually been demonstrated quite thoroughly. They already did extract electricity from that. Just not on a break even level. cant cook creole bream fucked around with this message at 20:21 on May 11, 2023 |
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May 11, 2023 20:17
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So the direct generation of electricity would be presumably way more efficient?
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May 11, 2023 20:36
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cant cook creole bream posted:I saw that video a while ago. That guy didn't really put a lot of effort into into be quite honest. He mentioned some stuff which was disputed long before and presented mechanical hurdles like huge impassable baricades as if nobody before him had ever thought about those. How does that make sense as an objection? For example, "Your reactor seems to have very little shielding for something that produces prodigious amounts of neutron radiation" is a legitimate objection; whether people thought of it before doesn't change that. quote:The biggest one ist the fuel. Most attempts at fusion are based on the combination of the hydrogen isotopes Deuterium (D) and Tritium (T). While D absolutely plentyful and quite easy to produce from seawater, T doesn't really exists and decays after 12 years. The only supply is from radiation in cooling water for fission plants. And the production is way below what ITER alone would need. It's not way below what ITER would need because ITER is just a research reactor, obtaining sufficient tritium for it is a known quantity. ITER doesn't breed tritium because, again, that's not what it's researching, but any D:T based power reactor would do so. Basically, "There's not enough tritium for D:T power reactors" is not a real objection because if you build a D:T power reactor you can produce all the tritium you want to. quote:Helion's fuel cycle effectively only uses Deuterium as input. It produces and uses Helium3 (aka Helion) as an intermediate step. This is very important and will have implications further down. Ask yourself, how does it produce He3? quote:Another big advantage is that pulsed generation can be scaled. If the energy grid is full, you can chose not to add further reactions on a whim, while a tokamak could only be useful other longer contiuous operation, which are hard to maintain anyway. This also means that you can clean the used fuel from the barrel after each reaction, which seems dubiously possible in tokamaks. Not even sure what you mean by "used fuel." quote:And then there is the big difference between netronic and aneutronic reactions: D T reaction produce almost all of their energy as fast neutrons (i.e. nuclear radiation .) While those are on another power level then the ones from a fission plant, you shouldn't stand near that. The only way to extract that energy is to do the same thing as yfission plants do. Heating and boiling water to make turbines run. Nope. I mean, yes, but that's a very incomplete picture. The cross-section for D:He3 fusion is far smaller than that for D:D fusion, which means under any conditions in which you are fusing D and He3, you are also fusing D:D. In fact, you allude to this above when you say the reactor produces He3 in situ. How's it do that? It does it by fusing D:D. When you fuse two deuterons, there are two possible reactions: D+D -> T + p That is, you had two deuterons, now you have a triton and a proton. The other is D+D -> He3 + n Note that this second reaction, the one you're relying on to produce He3, is *not* aneutronic. Each of these reactions has a 50% chance to occur, there's nothing you can do about that (and even if you could, you *need* the He3 one to happen). Every reaction that produces your reactor's He3 is accompanied by a high-energy neutron. And then the cross-section for D:T fusion is even higher than that for D:D (it's orders of magnitude higher than the cross-section for D:He3 fusion), and D:T fusion gets you He4 and another, much-higher energy neutron. In other words, for every D:He3 fusion event, you're going to have like 10-100 D:D events. For every 2 D:D events, you're going to get one ~2.5 MeV neutron and one ~14 MeV neutron and those are are going to both irradiate and escape from your reactor vessel. This is not aneutronic at all! And Helion doesn't seem to acknowledge this fact even in their reactor construction. quote:The cool thing about that? Protons have a magnetic charge. The same magnets, which squeeze the hydrogen can steal the speed of those protons and directly convert that to electricity, no water heating required! This is absolutely the least out-there thing about it. Extracting energy from moving charges is trivial. This concept was generated the first time someone moved a coil around a magnet. Phanatic fucked around with this message at 20:43 on May 11, 2023 |
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May 11, 2023 20:40
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I'm actually aware of these points. To be honest, I didn't want to bother going to much into the detail phone posting during my train ride. The main takeaway of the question was what the theoretical advantages compared to a tokamak were and even though it is not fully aneutronic, the concept remains that the energy is extracted from that part. The (relatively) fast ~2.5 MeV neutron for a He3 + n result is baked into the fuel cycle as an acceptable loss. As for the harmful side reaction between a freshly minted T and a D (i.e. the bread an butter of a tokamak) I am no particle physicist, but from what I've read, directly after creation, the T has too high of an energy level to instantly jump into a new fusion and by the time that would be statistically likely, the compression pinch is already over. Afterwards the chamber actually gets cleared out. That's what I meant by used fuel. Plus extracting finished He4 which just makes the process less likely. This extraction process is actually fundamental, because Helion wants to get the Tritium out and trade it for more Helium3 or to set it on a shelf for 12 years to get the same result. If it is electrical positive despite the loss from that neutron, it's good enough on that part. That loss of heat energy is actually a relatively part of the total cycle as opposed to the DT-tokamak, where it is simply the only outcoming energy. As for material and security concerns of those ~2.5 MeV neutrons: The simple solution is to put the reactor in a pit and replace parts at some intervals which might be long enough to be financially viable. I wouldn't advise standing next to that thing either. But if it is actually possible to make the ~14 MeV DT side reaction rare, the degradation and the dangers would be far less than what a tokamak with water cooling would produce. * Over the lifetime of the current model, there have been a large amount of fusion reactions and from that they can estimate the total tear of a productive system with a higher pulse frequency and built the chamber in a way resistant to it. That doesn't sound easy, but it's an engineering challenge, rather than some physical impossibility. Another approach, in case this proves futile is to split the reaction into two processes. You have one breeder-reactor which does nothing but turn DD into T and He3 and some nasty neutrons which you extract and another one which is supposed to be almost 100% aneutronic, which takes D and He3 as a fuel. Now you may argue that this produces D+D too, but there is no reason to make those two inputs symmetrical. If you put in 1 D for every 1000 He3, suddenly the reaction is skewed heavily towards D+He3 (Besides, David Kirtley did a presentation where he postulated that under the right temperature and pressure conditions D+He3 is more likely than D+D under the same input amount.) Such a reactor would be almost fully aneutronic. In fact the plan for Polaris is to work as such a breeder reactor to extract He3 and T. They mostly just want to see the effectiveness of that breeding and to produce fuel in that iteration. But their (honestly quite baffling) assumption is that the half of the cases where D+D -> T+p happens is already enough aneutronic fusion to make the breeder reactor electricity positive. I honestly don't buy that claim but we will see next year. Maybe they haven't considered the problem of neutrons enough. And maybe they will find out that it does not scale up as they expected. Heck, maybe it turns out that their magnetic plasma tori don't scale at all and the reaction doesn't happen in the first place. But claiming that they haven't considered these points at all, is frankly speaking a bit arrogant. * Neutronic discharge for Tokamaks might work with a lithium blanket, which extracts the heat and uses the neutron to produce new tritium. That's honestly an elegant solution. But as far as I am aware, no reactor prototype has one of those yet and it is not yet proven if that concept can work at all. cant cook creole bream fucked around with this message at 21:49 on May 11, 2023 |
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May 11, 2023 21:44
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Raenir Salazar posted:So the direct generation of electricity would be presumably way more efficient? Maybe but maybe not; the photovoltaic effect also directly produces electricity, but you can get comparable efficiency to a PV panel by just using mirrors to heat water. So while this fusion design does literally create current that's not the same as creating a usable source of electricity that's compatible with the grid, there will be extra steps that may be lossy
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May 12, 2023 00:45
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Family Values posted:I'm of course hopeful, but let's just say I'll believe it when I see it. There'd better be a lot more to their system than what they've disclosed to the public. This is quite good. It's short and covers the main problems because the obstacles here really are that basic. Some things the video didn't really address is the heating and confinement. Most tokamaks use a combination of a huge MegaAmpere pulse from a central solonoid, radiowave & microwave heating, firing MegaWatt particles into the plasma to even come close to the 100 million Kelvin needed for D-T reactivity to become significant and you need a factor of 10 (1 billion Kelvin) again for D-He3 to peak. It doesn't seem possible to achieve that with pulsed heating as they call it. You have to consider the collisions of all the particles in the individual "plasmoids" aswell. They are bouncing off each other and changing the magnitude of their velocity along the length of the device to velocity in the radial and perpendicular directions. Since the individual particles in the "plasmoids" have a significantly broadened velocity distribution, not all of them are going to make it through this compressed magnetic field at the centre and a lot of them are going to be reflected back to where they came from. The plasma that does make it to the centre need 3 things to achieve a sustained fusion: high temperature, high density and high enough confinement time before the particles are lost to the walls of the reactor. Even by their own numbers (submillisecond confinement time, 10^22 m^-3 density, ion temp 8keV) they would be far below the x-axis for the Lawson critereon which puts them in the 1960s or 50s:  Magnetic confinement fusion works because a low density plasma can have confinement time of up to 1 second to sustain fusion reactions. Inertial confinement fusion works because you have a plasma at such extreme densities (think the sun) that confinement doesn't matter. What Helion is doing is really like the worst of both worlds here. breadshaped fucked around with this message at 11:50 on May 12, 2023 |
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May 12, 2023 11:47
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Germany on track for the lowest monthly co2 emission of the last 12 months in may 2023, 6 weeks after shutting off the last nuclear plants, showing that while shutting them off before coal was not a good move, it's neither lead to increased emissions nor costs. It's been a good wind year so far with average sun hours, but in general nothing much outside of the long term average.
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May 28, 2023 18:59
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Well sure, if you just import half of your energy from greener countries when the sun isn't shining  
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May 31, 2023 14:24
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mobby_6kl posted:Well sure, if you just import half of your energy from greener countries when the sun isn't shining Yup, one of the few clearly good thing to come from the EU.
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May 31, 2023 14:34
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mobby_6kl posted:Well sure, if you just import half of your energy from greener countries when the sun isn't shining One weird trick that the nukechuds hate.
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May 31, 2023 14:48
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VictualSquid posted:Yup, one of the few clearly good thing to come from the EU. Except for the people in those other countries whose electricity prices have risen due to increased german demand.
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Jun 1, 2023 04:25
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https://slate.com/news-and-politics/2023/05/rich-republicans-party-car-dealers-2024-desantis.html https://www.bloomberg.com/graphics/2022-clean-energy-power-lines-transwest-wind-maps-private-property/#xj4y7vzkg Both the spread of EVs and the construction of transmission lines to send renewable energy have to deal with a lot of GOP 1%-er opposition. I'm not talking about billionaire opposition either here, but the actual largest faction in American 1%. Car dealership owners, mass gas station owners, construction company owners. The petty multi-millionaire failson and faildaughter that inherited a 30,000 acre ranch from their dad, and have stalled out a billionaire's transmission line project because they don't want anything to change* from when daddy owned the ranch. * except for the new trophy horse operation
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Jun 1, 2023 05:36
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His Divine Shadow posted:Except for the people in those other countries whose electricity prices have risen due to increased german demand. Germany is still a net exporter though.
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Jun 1, 2023 06:10
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cant cook creole bream posted:Germany is still a net exporter though. Yet it hasn't helped push prices down at all, guess it has to do when during the year they typically have a surplus everyone has less need of electricity, so they are lowering already low prices.
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Jun 1, 2023 06:43
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golden bubble posted:https://slate.com/news-and-politics/2023/05/rich-republicans-party-car-dealers-2024-desantis.html ahh, that's how we are motivating displacing people without free and informed prior consent, just label 'em a rich failson then job done? I got no love for GOP car dealership owners but opposition to economic development is the popular thing to do these days (who can support anything that is just for number go up?). I find it a bit amusing that a lot of the same people that yay and cheer impediments to nuclear development or a hydro dam are now bemoaning that someone might get a say on a powerline going down the guts of where they grew up.
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Jun 1, 2023 09:32
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Electric Wrigglies posted:ahh, that's how we are motivating displacing people without free and informed prior consent, just label 'em a rich failson then job done? No, you see the world is black and white and rich people are always evil in any situation if a poor person wins the lottery today he's automatically evil tomorrow. hth
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