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This molten salt thermal storage company just got a $26M first round and their concept looks interesting. It started at Stanford and then got into Google's incubator. Paper on the tech here, with numbers: https://aip.scitation.org/doi/10.1063/1.4994054  Looks like the two turbines shown in this cartoon are in reality the same single turbine:  They use a brayton cycle turbine to drive a temperature difference between molten salt and some kind of antifreeze (n-hexane in the paper) cold reservoir, then run it the other way to generate power. Their cold reservoir is 180K and their hot is 823K. For the temperatures they're targeting, they end up with a maximum theoretical roundtrip efficiency of 75% (that's electric->thermal->electric) which is very impressive IMO.
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Jan 10, 2019 00:10
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bawfuls posted:This molten salt thermal storage company just got a $26M first round and their concept looks interesting. It started at Stanford and then got into Google's incubator. That's really loving cool, and pretty sound from my understanding. Are the biggest issues still the salts themselves, and how corrosive they are? WHat kind of materials do they have to use to contain those?
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Jan 10, 2019 00:15
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They claim to be using cheap materials, no need for expensive high grade steel, etc. My understanding has been that the limitation on molten salt is the top end storage temperature (~600C), which limits your potential thermodynamic efficiency when converting back to electricity. But this system gets around that with the lower cold reservoir and by using the same turbine to drive both the E->T and T->E. edit: the paper I linked has a pretty complete overview of the technical limitations and advantages vs other systems. There is some discussion about maybe not being able to use the same turbine for both ends of the process. The salt in question (NaNO3/KNO3 eutectic) is apparently no problem for steel. bawfuls fucked around with this message at 00:40 on Jan 10, 2019 |
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Jan 10, 2019 00:28
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bawfuls posted:This molten salt thermal storage company just got a $26M first round and their concept looks interesting. It started at Stanford and then got into Google's incubator. Better than electrolysis/fuel cells.
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Jan 10, 2019 01:41
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quote:The marginal cost per stored joule, dominated by the cost of the storage fluids, is about $3.54 × 10−6 J−1 ($12.7 per kWh). (for context, thats almost exactly one order of magnitude below li-ion today)
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Jan 10, 2019 04:26
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StabbinHobo posted:
When considering this pricing advantage, keep in mind that this type of storage system is not as quick to respond to power needs as li-ion. We will see a blended system of a low cost bulk storage system like this and a higher priced system that is capable of 'instant' response being deployed by most power/generation companies.
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Jan 10, 2019 06:26
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bawfuls posted:The salt in question (NaNO3/KNO3 eutectic) is apparently no problem for steel. Stress corrosion cracking (SCC) is actually an issue for this kind of salt mixture in many/most steels especially at higher temperatures and pressures. It is a known issue for exactly this application with at least one documented case in an experimental concentrating solar plant with molten nitrate salt storage. In the "limitations of steel" section their paper uses fairly aggressive operating temperatures and pressures based on staying just below the limit for creep deformation in the steel, but doesn't address stress corrosion cracking at all. They just note that corrosive metal loss is small which....isn't really helpful since SCC failures can and usually do occur in only mildly corrosive environments. This kind of stood out as a yellow/red flag for me. I doubt it's an unsolvable problem and I remember from 2-3 years ago seeing studies with some proposed SCC inhibitors or alloy modifications for nitrate salt energy storage using steel instead of nickel alloys. So hopefully they've got it sorted out and it was just omitted from the paper for some reason (other than bullshitting idiot VCs)
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Jan 10, 2019 07:11
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That’s good info, I wonder how much it could be mitigated by higher (more expensive) grades of steel? Of course, that’s part of their value pitch, a lack of expensive materials.
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Jan 10, 2019 07:35
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My one month takeaway from this project is that wind is the option of last resort for people with nothing left, more ex-military guys than I've ever seen, and a few very talented folk rapidly going grey. Holy poo poo my dudes, what a hosed up industry. 
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Jan 15, 2019 15:40
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Rime posted:My one month takeaway from this project is that wind is the option of last resort for people with nothing left, more ex-military guys than I've ever seen, and a few very talented folk rapidly going grey. Holy poo poo my dudes, what a hosed up industry. Depressing, or is this just Sudbury?
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Jan 15, 2019 17:10
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Nebakenezzer posted:Depressing, or is this just Sudbury? This is the standard makeup for the industry in Canada, I understand, this isn't the first project for most of these guys. Wasn't really expecting a workforce of barely literate chain smoking alcoholics, should have just doubled my wage and gone to the rigs instead of having ethics and poo poo. Feels bad. 
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Jan 15, 2019 18:05
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PG&E (LA Utility) is going BK: https://www.bloomberg.com/news/articles/2019-01-14/who-could-get-hurt-by-pg-e-s-fire-driven-bankruptcy-quicktake Mainly because of the fire lawsuits (estimated costs could hit $30 billion) but I'm sure dealing with SONGS (nuke plant they broke) doesn't help. I have SDG&E and my rates (14¢/kwh ... and that's a discount) suck partly because of SONGS. But I don't use much electricity anyway. Only 288 kWh for the month.
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Jan 15, 2019 20:30
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VideoGameVet posted:PG&E (LA Utility) is going BK: https://www.bloomberg.com/news/articles/2019-01-14/who-could-get-hurt-by-pg-e-s-fire-driven-bankruptcy-quicktake SDG&E and SONGS is a different utility than PG&E. PG&E is shutting down Diablo Canyon (a different nuke) because it isn't worth the money to upgrade to meet incoming one-through cooling standards. At this point PG&E biggest asset is probably their downtown SF HQ building. Also PG&E occasionally blows up neighborhoods on the gas utility side, lest you think their issues are only with the E.
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Jan 15, 2019 20:37
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Trabisnikof posted:SDG&E and SONGS is a different utility than PG&E. PG&E is shutting down Diablo Canyon (a different nuke) because it isn't worth the money to upgrade to meet incoming one-through cooling standards. At this point PG&E biggest asset is probably their downtown SF HQ building. You are right ... it's owned by Southern California Edison (78.2%) and San Diego Gas & Electric (20%).
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Jan 15, 2019 21:54
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Rime posted:I'll dump when I'm out of NDA, I've already got stories which would make you When are you out of NDA?
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Jan 15, 2019 22:12
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VideoGameVet posted:PG&E (LA Utility) is going BK: https://www.bloomberg.com/news/articles/2019-01-14/who-could-get-hurt-by-pg-e-s-fire-driven-bankruptcy-quicktake Burning down half of Malibu and setting an old site filled with christ-knows-what 50-60s chemicals and a bunch of un-shielded nuclear reactors on fire and letting the smoke drift all over LA is a hell of a reason to declare bankruptcy Farmer Crack-rear end posted:When are you out of NDA? Looking forward to dis, will not lie
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Jan 16, 2019 00:32
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Is there a good reason the California National Guard hasn't been issued to seize infrastructure back from PG&E at bayonet point? Rephrased: what is perpetuating this joke of a utilities privatization experiment? For contrast, Southern Company is a hilariously awful manager of funds, but  totally-independent distributors aren't literally blowing houses out of existence on a regular basis.
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Jan 18, 2019 17:31
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Potato Salad posted:Is there a good reason the California National Guard hasn't been issued to seize infrastructure back from PG&E at bayonet point? What the hell are you talking about? PG&E has always been private, as were its various subsidiaries and predecessors going back to the 1850s. Southern Company is similarly wholly made of former private systems going back to the early 1900s.
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Jan 18, 2019 18:24
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fishmech posted:What the hell are you talking about? PG&E has always been private, as were its various subsidiaries and predecessors going back to the 1850s. Maybe he got confused. After all, state-sanctioned regulated monopolies are just kissing cousins away from being state owned/run.
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Jan 19, 2019 01:32
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Crewmate has been hospitalized with chemical poisoning. Turns out using a mix of simple green, super clean, windshield fluid and heavy-duty brake clean in enclosed spaces for months is probably bad.
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Jan 19, 2019 01:46
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PG&E is private without any of the benefits of an actual free market. Also, don't quote fish mech. Potato Salad fucked around with this message at 23:12 on Jan 19, 2019 |
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Jan 19, 2019 23:05
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Potato Salad posted:PG&E is private without any of the benefits of an actual free market. Free markets have never existed.
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Jan 19, 2019 23:14
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Rime posted:Crewmate has been hospitalized with chemical poisoning. Turns out using a mix of simple green, super clean, windshield fluid and heavy-duty brake clean in enclosed spaces for months is probably bad. based on your posting history, when you get out of your NDA go hither to the OSHA thread and be a superstar.
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Jan 19, 2019 23:22
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What's the thinking on Molten Salt Nuclear Reactors (and Stable Salt Reactors)?
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Feb 20, 2019 23:31
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They work just fine, more O&M from corrosion effects unless somebody pops out an additive or a molten salt formulation that would inhibit the corrosion at the wall-molten salt boundary. IIRC Dr. Garcia-Diaz was working on something similar-ish for a liquid lithium tritium breeding blanket for ITER when I left the DOE. Heck, she might have a project on it by now, I know IDL was wanting to get their design on paper dusted off for another look.
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Feb 21, 2019 01:52
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Got to gently caress around inside of, and manually restart, a 122 year old Westinghouse Pelton Wheel AC Generator last night. loving. Awesome.       The quality of engineering and machining on this thing was un-loving-believably beautiful, and it shows off. The slip rings on this are 100% original (everything is, it's never had a part replaced), whereas the slip rings in modern wind turbines regularly fail in about five years. A fully functional work of industrial art. Rime fucked around with this message at 04:39 on May 9, 2019 |
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May 9, 2019 00:34
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Rime posted:Got to gently caress around inside of, and manually restart, a 122 year old Westinghouse Pelton Wheel AC Generator last night. My father ran an 8 story Manhattan parking garage that was built pre-automotive. The elevator motors were installed some time prior to 1920 and were still going strong in the 1970's (the elevators were 100% manual, cable and counterweight design). Incredible design and quality.
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May 9, 2019 23:20
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Is this just a case of survivor's bias or were thinks some how made 100x better back in the day?
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May 9, 2019 23:30
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Baronjutter posted:Is this just a case of survivor's bias or were thinks some how made 100x better back in the day? Nah planned obsolescence is a hell of a drug. Things are built to wear out on purpose these days, if we kept building things that lasted 150 years nobody would need to buy new ones and that's bad for profit margins. Growing up my family used an old refrigerator that's pushing 100 years old and still going strong with minimal maintenance, it's still working to this day while the parents are on their second modern fridge in 10 years. Crazycryodude fucked around with this message at 23:38 on May 9, 2019 |
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May 9, 2019 23:35
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It also was probably hilariously inefficient.
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May 9, 2019 23:38
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Yeah probably. But while I am not a refrigerator engineer, I can almost guarantee that there's no inherent materials science or whatever limitation to building a modern refrigerator that can last 50 years instead of 5.
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May 9, 2019 23:42
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There's no reason to. Said 100 year old fridge was probably made almost the same way as one a decade or three later. Now there's typically rather significant changes in the same time frame, so people are more likely to replace it. (Energy efficiency is but one reason)
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May 9, 2019 23:49
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It's mostly survival bias and things today being built with a lot more "efficiency" / competitive on price / not being overbuilt. Planned obsolescence is just for a few kinds of electronics... if you fridge craps out after 3 years people are going to change brands. The boom in plastics in the 1950s/60s probably didn't help, either.
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May 9, 2019 23:51
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Crazycryodude posted:Nah planned obsolescence is a hell of a drug. Things are built to wear out on purpose these days, if we kept building things that lasted 150 years nobody would need to buy new ones and that's bad for profit margins. Growing up my family used an old refrigerator that's pushing 100 years old and still going strong with minimal maintenance, it's still working to this day while the parents are on their second modern fridge in 10 years. Of course, this assumes good faith efforts to make quality products instead of just the shittiest loving thing you can trick someone into buying for maximum $$$. So naturally it got murdered by capitalist greed.
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May 9, 2019 23:53
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Crazycryodude posted:Yeah probably. But while I am not a refrigerator engineer, I can almost guarantee that there's no inherent materials science or whatever limitation to building a modern refrigerator that can last 50 years instead of 5. I've never had a fridge that only lasted five years. Are you not cleaning the condenser coils or something? Anybody watching Chernobyl on HBO? First episode was some really good TV.
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May 10, 2019 00:09
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Crazycryodude posted:Yeah probably. But while I am not a refrigerator engineer, I can almost guarantee that there's no inherent materials science or whatever limitation to building a modern refrigerator that can last 50 years instead of 5. The value of something 25 years down the line, let alone 50, quickly approaches negligible. The 50 year refrigerator isn't obviously a better purchase at $2000 than a 10 year model at $1000.
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May 10, 2019 00:14
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The point is to not emit the carbon and landfill the raw materials that go into 5 fridges instead of 1. We don't all need the bleeding edge smartfridge when the planet's dying, a 50 (or 100) year old fridge keeps your food from rotting just as good as a new one.
Crazycryodude fucked around with this message at 00:30 on May 10, 2019 |
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May 10, 2019 00:27
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The only reason this is probably the last operating generator of its type on earth is because it has a tiny output. Even in its era, in the 10's, they brought in four outrageously loving massive diesel generators to handle the additional load the mines required. Like, yeah, it could theoretically run forever, and that's awesome, but it's been rendered obsolete from a utility perspective. Hell, it was functionally obsolete in generating capacity within years of installation, from how fast things were advancing back then. The company was going to scrap it in '95 when the last mine closed for good, but this dude saved it tied it into the grid instead. What I like about it is that you can tell the engineers cared, despite it being an industrial install. Knurled brass wheels, fine calligraphy everywhere, the swoop on the bearing pedastals. Today you just get a big shoddily-welded box in one color. Which will break down in a matter of years because nobody gives a poo poo.
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May 10, 2019 00:34
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Crazycryodude posted:The point is to not emit the carbon and landfill the raw materials that go into 5 fridges instead of 1. We don't all need the bleeding edge smartfridge when the planet's dying, a 50 (or 100) year old fridge keeps your food from rotting just as good as a new one. Metal is usually economically viable to recycle so it probably will be, and the older refrigerator is going to be significantly less energy efficient. That's not to say that the incentives currently in place don't prioritize short-term accounting over externalities like pollution, but there's also a case to be made for better engineering tolerances that allow for efficiency gains in manufacturing to a shorter lifespan - planned obsolescence if you will.
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May 10, 2019 00:40
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Is there true evidence things are made worse today? There are certain gimmick companies like luxury car brand and Apple phone that are easily breaking trash, but it doesn't seem most day to day thing break more easily than they used to. Even thing like TV now is more likely to break because it is thin delicate object with a big surface to shatter, rather than stop working natural. Many old appliance required frequent repair services to keep in working order as well. To say nothing of how if your refrigerator is much old, it contains refrigerant that is harmful to whole atmosphere and environment and sometimes you can not even refit the machine to use safe refrigerant. Or joint western standards of the 1990-2010 era that forced down more efficient power-water-other material usages in major device from heating system to clothes washer. I understand you can find much gimmick of some equipments that has been "working" since 80-100 year, but how much was the cost of maintenance and resource in repair plus inefficiency in that time. Who here have even need to replace the LED lightbulb, compare to old incandescent style that also used 7 times the energy? Is not ages of typical car on the roads in all major country now much longer than they were decades back? It seems to me that true quick-useless manufacture was of the immediate post WWII period, as all sort of appliance became mass available in the first world, paritucularly in Europe where there was not so uch in use before for being poorer than America in the public.
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May 10, 2019 00:44
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