The National Academies call for the US to be smart about new reactor designs:
"The race against climate change is both a marathon and a sprint," declares a new report from the US National Academies of Science. While we need to start decarbonizing immediately with the tech we have now—the sprint—the process will go on for decades, during which technology that's still in development could potentially play a critical role.
The technology at issue in the report is a new generation of nuclear reactors based on different technology; they're smaller and easier to build, and they could potentially use different coolants. The next generation of designs is working to avoid the delays and cost overruns that are crippling attempts to build additional reactors both here and overseas. But their performance in the real world will remain an unknown until next decade at the earliest, placing them squarely in the "marathon" portion of the race.
The new report focuses on what the US should do to ensure that the new generation of designs has a chance to be evaluated on its merits.
Most of the next generation of nuclear power designs fall into the category of what are termed small modular reactors (SMRs). These designs have two emphases: They are modular and could potentially be mass-produced, and they focus on inherent safety. Combined, these factors will theoretically allow for rapid and cheap production of reactors and a far lower footprint for the supporting power plant where the reactors are installed.
Many of them generate power by boiling water. But some use more unusual coolants, such as gas, molten salt, or liquid sodium. Every one of them, however, shares a critical feature: They haven't been built. All the expectations we might have about their costs, electricity production, and so forth are estimates. The only approved small modular design will first be incorporated into a power plant at the end of the decade—if everything goes well. Some other companies plan to be ready to go into production sooner, but their designs aren't yet approved.
While these designs are unlikely to compete on cost with renewables, they have a number of potential uses once the low-hanging fruit of decarbonization has been picked. These include helping with managing the intermittency of renewables, providing heat for hard-to-decarbonize industrial processes, and even desalination or the production of hydrogen (either for direct use or for the production of synthetic fuels).
The report acknowledges that the potential utility of next-generation designs is completely up in the air, noting that it will depend on "the evolution of energy policy, comparative economics with other energy technologies, the challenge of building plants on budget and on schedule, future energy demand and the structure of the grid, societal preferences, and the prospect of using nuclear energy for purposes beyond electricity generation."
(Score: 4, Interesting) by Rich on Monday May 01 2023, @01:28PM (13 children)
These people coming up with the concepts, and working the media so we have one story a month about these small modular reactors, who pays for them? Is it Bill Gates? Or some sort of public-private partnership with university people hopping from grant to grant? Running campaigns at that level ain't cheap.
I haven't done so in a while, so I'll re-iterate my positions here:
- If it's small AND has enough power density to be worthwhile, it can melt down from post-fission decay energy
- If the coolant is anything else but water, cost will be a magnitude higher. Sodium works, if you factor in your weapons budget
- If it's mass produced, enough of those will go derelict (see the state of Beta-M RTGs, and they weren't even privately owned)
- If it's privately owned, someone's banking on socializing the technical debt for the next 100k years.
In any case, the total cost of operation including complete disposal will exceed the price of purchasing or invading some sandland near the equator, plastering it with PV, and shipping home the hydrogen.
Yet, even with the above, I'd be tempted to accept the risk of an accident, if the operator proves it can safely and permanently treat nuclear waste. That could be by demonstrating a permanent storage facility at scale, by pyroprocessing the waste and chartering a few starships to shoot the residue into the sun, or whatever. It just has to happen, and reliably prove itself before any license is granted. And it should probably happen in the country where the majority of investment money is from. "Blood bonds" would also help, where the not only the investors are liable with their entire property, but also their heirs and offspring until all waste is dealt with, or for eternity, whatever is shorter. (That'd make a nice novel, btw)
(Score: 4, Interesting) by khallow on Monday May 01 2023, @01:40PM (7 children)
Keep in mind that US society isn't allowing operators to safely and permanently treat nuclear waste. We don't have breeder reactors to turn 100k year dangers into 1k year dangers. We don't have safe geologically sound depositories for those 1k year dangers. Thus, I consider this requirement voluntarily waived.
I agree on the novel, but I disagree on the bonds. A key problem again is the above: society deliberately making the harm of nuclear power worse. Thus society should be partially liable for the results.
(Score: 5, Insightful) by Rich on Monday May 01 2023, @03:20PM (6 children)
I guess the society is more inclined against haphazardous shoving of eternal waste into a primitive mountain tunnel. I don't think they would object methods that are reliable. Looking at the medium-activity "long term" storage in Asse, Germany, that's to be expected. They primitively piled up mild steel barrels with a thin paint coating in a salt mine. Go figure. That stuff is rotting and leaking not after 30k years, but already after 30 years. Also, the Finns have a high activity terminal storage at Olkiluoto (sp?) that already had problems with the water table before it went into full operation.
As for the breeder reactors for transmutation, we don't even have the means for splitting the actinides in a way that would allow "transmutation fuel rods" to be built to be stuck into a breeder yet. The major nuclear nations even gave up on the plutonium cycle, which is a tiny fraction of the reprocessing needed for transmutation, because it's to much of a hassle. As for the fast breeders themselves, they are (Dounreay, Superphenix, Monju, Kalkar not even completed) shut down and only the Russians keep Beloyarsk online. IMO, saying "safe terminal storage will be here real soon now", or the related "it's the greenies that hold up progress" is a bit like the mindset of Ford engineers designing the Nucleon, hoping that light and compact shielding material would be here "real soon now".
(Score: 1, Interesting) by Anonymous Coward on Tuesday May 02 2023, @12:05PM
Synroc [wikipedia.org] is all you need.
(Score: 1) by khallow on Wednesday May 03 2023, @02:55AM (4 children)
Society is far more comfortable with having that waste stored haphazardly on site at the nuclear plant. /sarc
That just tells me that the storage problem isn't being solved. You haven't actually mentioned any problems here that would harder than building nuclear reactors.
My take is that the real problems here are political factions that are playing the long game by destroying the nuclear industry's ability to mitigate future harm. Destroy their ability to recycle and store nuclear waste, and nuclear power will eventually shut down. Of course, there will be that modest 100k years of liability, but it's a small price to pay. /sarc
(Score: 2) by Rich on Wednesday May 03 2023, @12:14PM (3 children)
I assume solving the storage problem IS harder than building reactors, simply because the first hasn't been reliably done yet, but the latter has been done hundreds of times. Also, there are many kinds of waste, from all kinds of reactors, let's just look at the typical low enrichment light water power reactor wastes.
It has to be considered that no one yet has managed to even successfully do commercial reprocessing. The US had the Western New York reprocessing facility, which shut down reprocessing after 6 years, then continued as a dump site for 3 years and now can be considered nuclear waste itself in its entirety. No other commercial plant ever opened (2 in the US and Wackersdorf in Germany were shut down even before operation), Sellafield, La Hague and Rokkasho can be considered military (Rokkasho is about as science/commercial as the Epsilon rocket and the Hayabusa re-entry demo). Both Sellafield and La Hague dump waste into the sea at a level that would be entirely unacceptable for commercial operation. Germany stopped sending fuel for reprocessing in 2005 and declared the intention to terminally store the spent fuel as is. So here we have it: I conclude the PUREX process is not a viable path, or someone would have gotten it right.
I also (handwaving) assume that the sheer amount of complete fuel elements, as well as their construction, precludes putting them away for eternity as-is and therefore a waste isolation through reprocessing is needed. Waste isolating reprocessing would be needed for transmutation breeding anyway.
So, if not PUREX, what else? "Pyroprocessing" (I don't know the exact details, the state of the art can be read here: https://www-pub.iaea.org/MTCD/Publications/PDF/TE-1967web.pdf [iaea.org]) appears to be the next most promising approach. However, as the South Koreans wanted to move forward, they got intense pressure from the US to stop their research. Japan seems to get away with their bomb building efforts, but neither Korea does...(What are they going to do in the South now? Send it to the North for reprocessing?)
So the first thing needed to be demonstrated is a way of reprocessing that at least doesn't create even more waste in form of the reprocessing facility itself. After that, we'll start talking about safely enclosing each component of the resulting isotope zoo, in borosilicate glass, or synroc, or whatever, under the consideration that the material matrix will be unter radiation for thousands of years and the waste occasionally changes its chemical composition in place (including to a gas) along the decay chain. Or alternatively, how a breeder reactor with enough neutron budget for external waste transmutation would look like. (Very oversimplified: fast fission average neutrons: 3. Fission fragments in need to be transmutated themselves (or just capturing): 2, neutrons required to sustain reaction: 1).
I don't think that any of the issues can't be solved, I even think they HAVE to be solved. It just doesn't work out when considering classic economics.
(Score: 1) by khallow on Wednesday May 03 2023, @02:26PM (2 children)
Actually, in the US, the storage problem has been done many dozens of times in the past few decades (local storage as I have already noted), while no new nuclear reactors [wikipedia.org] have been built in the period between 1977 and 2013 and only two thereafter ( at Vogtle Electric Generating Plant [wikipedia.org], possibly completed this year).
What makes you think they didn't get it right? I think the real problem here is that a working PUREX would be a blow to anti-nuclear political factions since it would mostly solve the waste disposal problem, so it needed to fail. Consider the years of operation of the only plant that was open for commercial operation: Western New York reprocessing facility 1966-1972. Are we really to believe that no one could have come up with fixes to its problems over the past 50 years?
Similar examples of this in practice is the interesting legal opposition to projects like the John W. Turk Jr. coal plant (which generated supercritical steam), the Yucca Mountain nuclear waste depository, or the Keystone XL pipeline. Certain types of projects are going to generate years of litigation because of their relative safety or efficiency not because of their risks!
(Score: 2) by Rich on Wednesday May 03 2023, @03:34PM (1 child)
Your view is really US centric and has a vibe of conspiracy theories. There have many NPPs been built and are being built since the US stopped doing that. The capitalist US stopped it (and before TMI), because it wasn't economical in a purely commercial setting, even with externalizing the waste issue. I suspect the AP1000 contract for Vogtle was a political thing to keep Westinghouse and the entire nuclear industry in the US from going under and also maintain a competitor to the VVER "threat". Germany had the Konvoi series in the 80s, France the N4 in the 90s and is now struggling with their EPR legacy. The Russians are building a VVER in Bangladesh, of all places, right now. And the Chinese take a few of every of those to copy the best bits. They are even building a fast breeder atm, but that's not for economic reasons, but because the US cancelled the ABM contract and they want to keep their ability to nuke the US.
You'll get NIMBYs for every technical project, windmills are as bad as everything else in that regard.
For all the PUREX issues, the German wiki article is really good (deepl.com should do), it even ventures into the possible alternatives.
(Score: 1) by khallow on Wednesday May 03 2023, @11:22PM
It would have to be covert first in order to be a conspiracy. Shutting down new plant construction and closing off means to safely dispose of waste conveniently leaves a bunch of aging power plants with no upgrade path. Nuclear power will end sooner or later under that scheme. I bet many of the people involved are surprised at how long nuclear power has lasted under those circumstances.
Same goes for Japan and Germany. Japan lost a whole generation of plants that were to be built from 1995-2005. And Germany is in the final stages of shutting down its nuclear power plants because of Fukushima even though the key problems have nothing to do with German nuclear power.
In 1972 with plentiful enriched uranium supplies and low disposal costs. Now, there's tens of thousands of tons of fuel rods melting a hole in power companies' budgets. Better tech and more at stake. So why isn't anyone trying? A: they'd have to survive the tidal waves of lawsuits first.
(Score: 3, Informative) by DeathMonkey on Monday May 01 2023, @09:48PM (3 children)
EPA's SuperFund program was intended to be a "polluter pays" system for cleaning up the worst contamination by making polluting industries pay into a cleanup trust fund ahead of time.
However, in 1995 Congress allowed all those taxes to elapse so now we the taxpayers cover the bill.
Funding the Future of Superfund [pirg.org]
(Score: 1) by khallow on Wednesday May 03 2023, @02:58AM (2 children)
Except it was intended to clean up existing polluted sites and thus, there would be no "ahead of time".
(Score: 2) by DeathMonkey on Wednesday May 03 2023, @03:10PM (1 child)
No, there is a process for adding new sites and new sites are added all the time:
Proposed and new Superfund sites 2023 [epa.gov]
(Score: 1) by khallow on Wednesday May 03 2023, @11:10PM
Even so, a site doesn't get added to the National Priorities List, until it's a priority, savvy?
(Score: 2) by PiMuNu on Tuesday May 02 2023, @09:53AM
> some sandland near the equator
Why invade. US has several massive deserts that are mostly full of nothing.
(Score: 2) by JoeMerchant on Monday May 01 2023, @01:51PM (4 children)
Read it in the voice of "Plastics" from "The Graduate":
Politics m'boy, Politics
It was the past, it is the future, it is the all-defining gateway for nuclear power, everything else is pretty simple by comparison.
🌻🌻 [google.com]
(Score: 2) by RS3 on Monday May 01 2023, @05:00PM (3 children)
That and economics, which obviously go heavily hand-in-hand.
And then you have one of my favorite: "popular misconception [wikipedia.org]", which is pretty hard to beat, esp. with for-profit news media. TBF, they often and thankfully dispel many inaccuracies and misconceptions too.
(Score: 5, Interesting) by JoeMerchant on Monday May 01 2023, @05:24PM (2 children)
The economics of nuclear power is how politics controls it. If politics put as much "safety" hurt on coal as they do nuclear, preventing injury and environmental contamination from the mining and burning of coal, coal based electricity would cost far more than nuclear power. Not saying I want to play fast and loose with nukes, but they have turned the dial up way past 10 and it seems like much of the "safety requirements" are a politically acceptable way of saying "no nukes in my backyard until you pay, and pay, and pay."
🌻🌻 [google.com]
(Score: 2) by RS3 on Monday May 01 2023, @05:45PM (1 child)
If I told you how much these quite simple coolant flow detectors sell for, compared to their cost, it would just add fuel to your fire. (had to mix sarcasm w/facts there...) But they do have a 40+ year life expectancy, so they end up being low cost in the long run. My point is: whenever "safety" requirements are increased, prices go skyward (due to absolute demand). It wasn't that long ago that a GFCI outlet was like $3.50, and maybe $9 for a pack of 3. Now that NEC has increased the need for them, exact same thing goes for much more $. I see them at $20-28 now. Pack of 4 for $56.
So yes, your points are all spot-on, and I wish I really understood politics...
(Score: 2) by JoeMerchant on Monday May 01 2023, @06:30PM
Prices in home building supplies have a suspiciously "whatever the market will bear" aspect to them.
Our local nurseries have raised some of their most common landscaping plants prices as much as 10x during the recent house building boom - pretty hedge bushes that used to sell for $5 they're asking $50... trees that used to go for $25 are now $250. Builders gotta have 'em to get their certificates of occupancy, so...
Sooner or later, they'll ramp up GFCI production volume to meet demand, but I doubt they'll drop the prices, just wait for inflation to catch up with them.
🌻🌻 [google.com]
(Score: 4, Insightful) by istartedi on Monday May 01 2023, @04:17PM (22 children)
What do I mean, it should be like flying?
I'm talking about how the military trains pilots. I don't know what the percentages are, maybe it's gone down but a fairly hefty chunk of our airline pilots got their training in the military. Aside from the training, it instills a sense of discipline and weeds out some bad characters. A lot of them wanted fighters, but ended up flying cargo and they're still excellent pilots because they generally don't let numbskulls take $100 million dollars and dozens of lives in to harm's way.
Those guys come out and commercial aviation is probably a cake walk by comparison.
We already train nuclear reactor operators in the Navy, we just don't use them as much in civilian life AFAIK.
The new civil reactors should operate, as much as possible, the same way Navy reactors do. Of course the designs will be different, they are likely to be larger; but they should use similar interfaces and controls. To the extent that we can do this without compromising classified information (and I think that's possible) a Navy nuclear reactor operator should be primed for civil reactor operation after leaving the service.
Appended to the end of comments you post. Max: 120 chars.
(Score: 5, Interesting) by RS3 on Monday May 01 2023, @04:54PM (16 children)
I'm not expert, but safe nuclear power has been a strong interest of mine for a long time. I was always into science and technology, and learned the simplest basics of fission and power generation. When I was still a kid the Three Mile Island accident [wikipedia.org] happened. What little I knew about the specifics, I was sure that better monitoring and controls would have helped, and of course it turned out I was right.
Full disclosure: a few years ago I found a little occasional job (gig) where I actually build, repair, and test flow detectors that are used to detect reactor coolant flow, so I have some inside info. Tiny company of course, and the market is all but gone as some of the customers' plants that I built / repaired flow detectors for are now shut down (stupidly). When I met the owner of the company that makes the detectors he said "If TMI had had our system, you would never have heard of TMI". Obvious implication being: the accident occurred because they didn't know if coolant was flowing and/or if the reactor core was uncovered.
As an engineer I see far too many systems where they compromise on sensors and instrumentation, and basically "surmise" some things that they could actually measure. That's all well and good when everything is working as intended. But it seems nobody tries to anticipate the many possible malfunction scenarios, especially when two or more anomalies or failures coincide. To be fair, there are usually some people trying to raise a red flag but money-focused management shuts them down and we have things like 737MAX / MCAS, Challenger, Colombia, on and on. I learned at a young age if I tried to point out potential problems, I was a "complainer", "troublemaker", "roadblock", "pessimist", etc.
Point is: you could have the best "Top Gun" flyer or nuke operator, but if they don't have good instrumentation, they're crippled.
Not sure if you know names like W. Edwards Deming, Tom Peters, et al, but if there was a way to make those quality-only philosophies the main paradigm, we'd have a very different world. I wish people like you and I and many here were totally in charge. As long as the more money-conscious are running things, we'll continue to have preventable disasters, and then the great harm to public opinion, which is why nuclear power stopped being built in the US 40 years ago (IMHO).
(Score: 4, Insightful) by JoeMerchant on Monday May 01 2023, @06:25PM (14 children)
We have a deep well system for our home water. Built in the 1960s, originally the ground source was effectively a spring, just open the valve and you had 6 to 10 feet of "head pressure" to fill a tank with. Somewhere in the 1970s the local utility put pumps drawing water from the aquifer which made that spring head pressure unreliable, so they paid to install submersible pumps so people's wells would keep flowing like they used to. Even as late as 2016 we had a hurricane, no power for 3 weeks, but the submersible pump wasn't necessary, the head pressure filled our tank to 5' above ground level.
So, that tank feeds a 3/4 horsepower shallow well pump that fills a pressure tank, so we have 40-65 psi in the house. Never was a problem with the tank being full, so the shallow well pump just had a simple high/low pressure contactor switch on it. Well, in 2018, we had two massive lightning strikes within a couple of days, and the 50 year old submersible pump fried. Wasn't long before we started having problems with the shallow well pump running dry, overheating, melting the PVC pipes attached to its iron body, etc. and eventually that old pump died, so I put in a new one. Just this past weekend we had another run-dry event, and even though the new pump is advertised to have "overheat protection" circuitry, apparently that cutoff point isn't low enough to prevent it from heating the water sufficiently to soften the PVC, which then expands under pressure and not only leaks at the thread joints, but no longer is compatible with slip fittings due to the expansion of the pipe... Now, CPVC for hot water would survive a bit more abuse, but how many CPVC fittings do you find at your local Home Depot/Lowes as compared with PVC fittings? Yeah. Further, there are things called "low pressure cutoff" switches which would shut off the pump in the event of a loss of feed water, but do they equip the pumps with those by default? No, they do not, that would cost an extra $0.50 per unit, and prevent breakdowns and re-installations in the future, why would they provide such a thing in any easy format for the consumer to obtain?
Yeah, so I have re-built the system with a bunch of galvanized fittings leading at least 18" away from the pump body - the galvanized pipe and fittings actually cost more than the pump. What I really want/need is basic instrumentation on the relevant variables in my system: a reliable tank level indicator would be a good start: Tank is getting low, shut off the pump - duh. Pressure into the tank feed would be another nice one to have, a high resolution log of that would have shown me when the (shared well with neighbor) neighbor's Jerry rigged pipe repair blew apart, speeding up the debugging process to find the problem and fix it. Pressure at the output, pump on/off state, all that into something like a Pi Pico serving up a webpage with the data to my WiFi and we'd be in great shape.
That's just the water system for two houses with 10 residents total, pump replacement is more annoying than costly, new pumps are available off-the shelf from any one of 5 stores within 5 miles drive and the pumps run $125 to $200. So, yeah, I'd like to have more instrumentation and controls to prevent failures, but we're doin' o.k. without it still. How they thought that NOT instrumenting EVERYTHING POSSIBLE in a freakin' nuclear reactor cooling system situated in the middle of a population of 30 million people was acceptable is beyond me. Yes, sometimes the instruments themselves fail and everything is o.k. sometimes the fittings for the instruments cause a problem, so you have to ask yourself if it's really worth the added complexity for that piece of data, but cost? Who can't do the math on risk-benefit when the risk is nuclear core meltdown to a water table clearly visible because your plant is in the middle of a RIVER!!!? If a $50K installed/maintained cost flow sensor reduces the risk of a serious problem by 0.001% across the coming 50 years, it's WORTH THE MONEY.
🌻🌻 [google.com]
(Score: 3, Interesting) by RS3 on Monday May 01 2023, @10:13PM (13 children)
Preach it brother!! I'm so of that ilk it doesn't even occur to me to not have instrumentation wherever you can. Sometimes I wonder about the whole design process. Sometimes I think people are too clever (coders included). I'm big on brainstorming, design review, etc. Too much ego to have small numbers of people designing things, not to mention human error.
I've had water wells most of my life. Always deep- 150 - 400'. Some people have very shallow wells. Interesting you're getting good water artesian. Best is to have it lined and grouted in, but I'm sure you know what you're doing there.
I'm sure you know about jet pumps too. I've never had one but some neighbors do.
Right now I have 2 wells- old and new. Old is 150', but can run out, so ~25 years ago we had another drilled that came out to 400'. Problem with old well: it would be simple, many methods, to know the well water level. I did put in one of those low-pressure cut-off control switches, but, it's by no means foolproof. The pump can be running pressurizing the tank, run out of water, it keeps running, pressure switch is happy but in mid-pressure. Flow sensing would help a lot, and is easy to do. Well level could be a float switch just above the pump, or an ultrasonic "sonar" looking at level, or a pressure sensor at the bottom would work very well.
In your case, I'm troubled that the pump can get that hot! I'd want my own temperature sensing and turn it the heck off before it gets hot enough to melt PVC.
You could use stainless steel fittings. SS is far less thermally conductive. Again, I'd rather sense the heat and shut the thing off.
Aforementioned reactor cooling water flow sensing is simply an ultrasonic "listener". It's called an "accelerometer" but it's just a piezoelectric transducer strapped to the pipe. Contact microphone if you will. In the reactor case, the pipe is too hot, so there's a rod- maybe fiberglass- I forget- that's maybe a foot long, and a large band strap around that. Just for grins, frequency range might be 1k - 100kHz. You could easily run flow tests and characterize the spectrum for a given sensor + piping. It doesn't measure flow rate, but based on a set threshold decides if there's enough flow. It's pretty clever really. I doubt you could truly calibrate it, but you could profile the acoustic spectral energy over the full flow range and worst-case scenario use a good old look-up table to give an approximate flow rate output. In your and my well situation, just knowing there's flow should be good enough. I'd love both flow and well level. Oh heck, why not have an app for that. :)
BTW, you may know- new thing with well pumps is tankless, or very tiny tank. Pumps are 3-phase and they control pump speed to keep pressure constant.
(Score: 2) by JoeMerchant on Tuesday May 02 2023, @12:10AM (12 children)
Yeah, I looked at tankless when the old pump died, but the existing system worked well ( ;-P ) enough it didn't feel worth re-engineering it.
Pressure sensor in the tank is my next thing. I got a cheap wireless ultrasonic level sensor, it only worked for two months, then the sensor quit, that was about two months ago. There's not enough room above the normal water level in the tank, only about 4-5" to the sensor so it quickly caked up with limescale.
Our well is about 200' deep in a limestone formation, good for drinking, bad for things that don't like calcium deposits.
Neat sonic sensor system.
🌻🌻 [google.com]
(Score: 2) by RS3 on Tuesday May 02 2023, @12:29AM (11 children)
Yeah, pressure sensor should be good. Look for pressure rising with pump on, obviously. It's possible you could use water faster than the pump, but not likely.
I should have more limestone in my water but have very little. More manganese. Lots of limestone underground- several quarries not far away.
Tank: you're referring to the non-pressurized tank? Most pressure tanks now have bladder, as I'm sure you know and likely have.
I assume there's a way to filter / absorb the excess limestone? I think softener will remove it.
Gee, for your tank level sensor I'm suddenly thinking of an automotive fuel tank level sensor...
(Score: 2) by JoeMerchant on Tuesday May 02 2023, @01:54AM (10 children)
Oh, meant to say depth sensor (which is pressure, but sensitive...) Maybe this one: https://www.amazon.com/dp/B07PXFPPMM/ [amazon.com]
Prefer to toss that in the bottom of the unpressurized tank and just shut off the pump that draws from it if it ever gets even half empty, if it's slow filling (meaning: problem with the submersible pump) the system could still work semi normally pausing the pressure pump (that fills one of those bladder tanks). Normally the water level never drops more than an inch.
🌻🌻 [google.com]
(Score: 2) by RS3 on Tuesday May 02 2023, @02:53AM
That sensor looks awesome- thanks. Yeah, seems like a no-brainer with that.
This might be simpler? https://www.amazon.com/Switch-Sensor-Stainless-Double-Controller/dp/B08CTY9L8G/ [amazon.com]
(Score: 2) by RS3 on Tuesday May 02 2023, @02:56AM (8 children)
Or this one: https://www.amazon.com/Aopin-Stainless-Plastic-Controller-Aquarium/dp/B095HQB8Q2 [amazon.com]
Or this: https://www.amazon.com/Jiayouy-Plastic-Switch-Control-XSL-3508-P/dp/B07Q1GJ7JL [amazon.com]
(Score: 2) by JoeMerchant on Tuesday May 02 2023, @09:51AM (7 children)
Yeah, the question is: am I going for simple pump control, or do I want a Pi Pico involved so I can monitor from my phone, control some irrigation valves, etc. So many other projects in flight I will probably do nothing for quite a while.
🌻🌻 [google.com]
(Score: 2) by RS3 on Tuesday May 02 2023, @03:30PM (6 children)
In one of the above posts I half-jokingly mentioned an app. I've used older laptops that still have parallel ports for digital I/O, but yeah, some kind of Pi or similar would be an awesome project. You could integrate home security system, monitor refrigerator / freezer temperatures, and who knows what, as well as the water system. This sounds like a journal story. :)
(Score: 3, Informative) by JoeMerchant on Tuesday May 02 2023, @04:01PM (5 children)
I have a couple of Pi Picos in the yard, one solar powered, the other charging a battery from 12V yard light power when it is on. The solar power one has been running continuously (sometimes from battery) since September of last year. Both run a little web server that allows control of ultrasonic emitters from any web browser in our local network: phones, computers, etc. So, when the neighbors dogs are going nuts, we can "bark back" - dog behavior modification is mixed, but better than nothing - but the solar powered Pico is super impressive to me - 24/7 webserver availability, and the Python code hasn't crashed in months, even with active use.
There's another project "in the pipeline" to put a Pico by the entry gate with a microwave motion sensor to give a doorchime type alert (bird calls, actually) when somebody is driving in the gate. That's a shaded location, but there's 12V lighting so it will be another vampire system - when I've got the time to do the physical assembly, battery power system, software, etc. The bird call door chime is already built and running in the house on a PiZero driving a PC speaker. It has been triggered by a Zone Minder setup watching some cameras, but as the PC that Zone Minder is running on has gotten older, it has started to run hotter and spin the fans more so I took Zone Minder offline. Also, Zone Minder will trigger the bird call alerts sometimes for cloud shadows, and every day at the sunset transition to black and white on the cameras, etc. Hopefully the microwave motion detector will have fewer false positives.
Then, we've got a small 4 zone irrigation system on a bluetooth controlled AA battery powered timer valve thing. Those batteries run a little over a year, so that's not too bad, but I'd really rather have it a little smarter, accessible from anywhere and not just within 20' of the device, plumbed more directly into the water source (direct from the deep well instead of running from our drinking water system), etc. That would be located in the "pump house" with 110/220VAC available, so no power challenges, but I'd still probably go with latching solenoid valves instead of continuously powered NC. With wall power available, it's also tempting to multi-function in a higher power ultrasonic emitter there. But... there's a kitchen remodel in progress with about 200 hours of work remaining before we're really "done" with that, landscaping projects, etc. etc. so the Pi Picos sit in a box, waiting...
🌻🌻 [google.com]
(Score: 2) by RS3 on Tuesday May 02 2023, @05:15PM (4 children)
You are way too cool. Thanks for the inspirations.
I haven't used any yet, but there exist low-power long-range RF communication systems. Data rates are slow- perfect for everything you're doing, but wouldn't do 8K video (as if that was necessary anyway). "Zigbee", "LoRa" are two I can think of right now.
https://en.wikipedia.org/wiki/LoRa [wikipedia.org]
https://lora-alliance.org [lora-alliance.org]
One interesting guide: http://edge.rit.edu/edge/P11252/public/Low%20Power%20RF%20Guide.pdf [rit.edu]
If you've got wire running to the gate, you could power it 24/7 and use the LoRa to control lights on / off and whatever else (camera?)
There are nice motorized valves available. Simple ones have built-in limit switches to stop the motor when the valve is fully open or closed. Hydronic heating system flow control valves are a great example. They usually run on 24V.
(Score: 2) by JoeMerchant on Tuesday May 02 2023, @07:45PM (3 children)
LoRa is very tempting to run from the house to the marina, some 5 miles away, but I'm not sure what the point is of having an independent channel run that far when 5G is also available... I've got solid WiFi coverage around the yard, and the Pi Pico only consumes a couple of milliamps when on server-standby listening for an http client to connect.
The wire to the gate is at the end of a long string of lights, two conductors in parallel, so I'd really rather just keep those dozen or so light connections simple. The cameras run PoE, so just a direct-bury capable Cat6 cable from the router to the camera. Due to lightning considerations, I've got a mesh WiFi system and the big long Cat6 cables in the yard tie in to satellite mesh nodes - no direct conductors to the main house network, but decent bandwidth, and the mesh nodes are what make the WiFi coverage in the yard so good.
There's so many kinds of valves in the world, these are the ones I'm thinking of using for the irrigation system when it finally gets here:
http://www.vegetronix.com/Products/Valves/ [vegetronix.com] They're basically the same thing that battery powered BLE water timer uses.
🌻🌻 [google.com]
(Score: 2) by RS3 on Tuesday May 02 2023, @09:26PM (1 child)
Those valves look awesome. I'll call BS on their energy savings thing. They're obviously using energy from water pressure to actuate the valve. For sure the low current is a huge factor in very low electrical power situations.
Thanks for the explanation- I didn't quite understand your whole setup. My main thing with the LoRa was where you were talking about solar / battery powered things, and WiFi is quite power hungry, and Bluetooth is still more power hungry, and very short range, compared to LoRa. But again, I didn't understand your whole situation.
I've been sort of trying to help a friend who has a side job working in hydrogeology. He and others have to go to a remote place, at least an hour's drive, every 6 hours, to measure test well depths, stream depth and flow, etc. Besides using a depth gauge, which is a very long tape measure with an electronic water sensor at the end, they have submersible data loggers they pull up once a week or two and read out the pressure and temperature data. Those things are very expensive and fail surprisingly often.
There is an Internet-connected pump station, so LoRa stuff could communicate back to the pump station. Someone would still need to check things, take manual readings, etc., maybe once a week or so, just to be sure. I'd love to do the project but I don't live near the operation and communication with aforementioned friend is scant / sporadic on a good day. He and others spend so much time doing it, then huge time analyzing data and writing reports to various govt. agencies.
(Score: 2) by JoeMerchant on Wednesday May 03 2023, @12:15AM
The efficiency of those pulse valves is that you only energize them on the change, for 50ms or so, as opposed to NC valves which are powered the whole time they are open. We are using an off the shelf Bluetooth low energy water timer which ran for over a year on 4 AA cells, just changed them. It is cycling an average of about 5 valves per day either on or off, but I only connected via Bluetooth about a dozen times on that set of batteries.
I'm just thrilled with the low power requirements for a WiFi server on the Pico, there are other micros as good or slightly better. It only serves 20ish pages a day (probably could serve a few thousand on my solar panel), they come up in one second or less, and it's pretty much all at default configuration from the Python environment.
USGS has lots of water monitoring stations and I believe satellite link is pretty common for them, though you will also see YAGI antennas and other things providing connection.
At the boat I have shore power, or 600AH @ 12V so 5G is well within power budget there. I keep meaning to do something with a Google Fi data sim in an old phone but $.01 per MB adds up and I find Android development annoying as well.
🌻🌻 [google.com]
(Score: 2) by RS3 on Tuesday May 02 2023, @09:29PM
Sorry- I mean to add cell network communication to the list of much higher power systems compared to LoRa (or whatever other similar systems exist).
(Score: 3, Informative) by PiMuNu on Tuesday May 02 2023, @10:13AM
It's not instrumentation, but you might be interested in Cockroft's follies:
https://www.bbc.co.uk/news/uk-england-cumbria-29803990 [bbc.co.uk]
(Score: 3, Interesting) by JoeMerchant on Monday May 01 2023, @05:57PM (1 child)
USNRC recruited me straight out of grad school to be an on-site plant inspector, made a pay-competitive offer and everything. Thing was: A) I didn't like the "2 years at a location and then you move" aspect of the job, and B) nuclear in 1990? even my 22 year old cultural antennae were well tuned enough to call B.S. on the NRC guy's "oh, there's plenty of new plants going to be built in the near future, passively cooled designs, minis..." line. Work 10-12 years as an inspector for the NRC and what do you do for an encore?
Now, think about this for a moment: your federally employed safety inspectors are, largely, composed of kids hired straight out of school who were gullible enough to go for that B.S. Highest paid position on the GS scale, you'll be at six figures after a few years...
🌻🌻 [google.com]
(Score: 2) by RS3 on Monday May 01 2023, @10:17PM
Join a circus doing a "I can make florescent things glow in the dark" show? :)
Dumb, I know, but I had to...
(Score: 2) by turgid on Wednesday May 03 2023, @01:15PM (2 children)
That's a great idea, but it would only work if the civillian reactors were of the same design (Pressurised Water Reactor) as the Navy reactors.
In general, despite their fancy names, modern designs are just that: PWRs with the cooling loops nice and high up so that natural convection can remove decay heat in an emergency.
I dipped my toes in the UK nuclear industry many years ago and our reactors then were mostly gas-cooled. Their reactor physics, their behaviour, was very different from the PWRs used at sea. We had ex-submariners on staff, and they were interesting people indeed. They had to be trained extensively to operate our gas-cooled reactors.
In the UK, we had some experimental fast reactors, which were liquid metal cooled and could be configured either to consume or to produce plutonium (high-level waste/fuel for nuclear weapons). Again, the reactor physics were very different requiring different training for the operators. I never saw them personally.
We, as a society, need to get over our fear of civillian nuclear power and our pathological obsession with trying to run it at a significant financial profit. We need to see it as an investment in ourselves, an investment in relatively clear, reliable energy production and we need to further develop our designs that consume plutonium. It's fuel! It could be used and consumed to provide us with energy. Instead we leave it sitting around, afraid to do anything with it, or we put it in weapons of mass destruction.
There have been all sorts of interesting and novel designs for nuclear reactors over the decades. Some are very safe and clean indeed. The main challenge is being able to safely remove decay heat in an emergency. There have been many designs where the reactor can cool itself naturally and passively, provided the cooling circuits are intact. You need to be able to avoid meltdown and re-criticality (with old fuel, containing plutonium, there is a positive temperature coefficient of reactivity).
There have been designs proposed where the reactor is in a sealed concrete building which can be left for 30+ years without human intervention. This means it can be made very strong, safe and reliable. That's the sort of thing we should be aspiring to.
And as for Bill Gates, his "new" reactor is just a fast reactor with bells and whistles. It's the WIndows 95 of nuclear reactors.
I refuse to engage in a battle of wits with an unarmed opponent [wikipedia.org].
(Score: 1) by khallow on Wednesday May 03 2023, @11:29PM (1 child)
On the second, if it's providing more value than cost, then it's likely running at a profit.
(Score: 2) by turgid on Thursday May 04 2023, @07:20AM
There may be a financial profit eventually. For me, the biggest profit would be the reduction in greenhouse gas emissions which would make life better for us all and make us more productive and healthy in the long run.
I refuse to engage in a battle of wits with an unarmed opponent [wikipedia.org].
(Score: 4, Interesting) by VLM on Monday May 01 2023, @09:00PM (5 children)
My understanding of the problem as a long term energy investor who knows about nukes and related items as a civilian investor-type, is there's plenty of small modular designs, all classified military designs, but there's very few big players in the industry and they work the civilian and military sides at the same time, and they don't want to piss off the military contract sides by essentially declassifying the latest sub/carrier designs, so they have to pretend to invent civilian designs on their own.
Rephrased, the problem is the civies want to build declassified USN S9G reactors then the navy throws a fit and says "no". Ironically China and Russia I'm certain have better documentation of our reactors than we do as Americans, so declassifying won't actually release any information to foreign governments.
Really the only countries with a hope of selling small civilian reactors are those NOT using small reactors for military purposes. Maybe Costa Fucking Rica could get into the civilian small nuclear reactor business.
(Score: 2) by Rich on Tuesday May 02 2023, @01:20AM (1 child)
I don't think there's much to declassify about any of the shipborne reactors. Their (not-so-)secret is in that they run on highly-enriched uranium. That's a non-starter for civilian use, and even more so for export. The navy reactors might even make compromises in efficiency vs. size or so. Also, I don't see how you would end up with a significantly smaller power plant than now. E.g. the VVER vessel is 4m in diameter (*) by 11m length, how much smaller will you go for a powerplant? The bio shield concrete is needed anyway, and with that you want a big ass turbine to make up for all the building effort spent for the nuclear part.
(*) They did that, so they could transport the pressure vessel on trains, but it leaves its walls in close proximity to the reaction, which in turn makes its walls brittle rather quickly with the neutron flux, so they came up with an "annealing" process to somehow make the brittle steel last a bit longer. Cf. e.g. "Annealing of a VVER-440 reactor pressure vessel in Loviisa". The same consideration has to be done for any other "small" design.
(Score: 2) by turgid on Thursday May 04 2023, @07:28AM
The British AGR design solved that problem by integrating the biological shield and pressure vessel into one pre-stressed concrete structure with a steel liner to make it gas tight. The primary cooling loop, including the boilers, was all within the pressure vessel/biological shield. The reactor core had "re-entrant flow" for the carbon dioxide coolant, which meant that the cold gas was passed through the graphite moderator in dedicated coolant channels before being passed over the fuel. This had the effect of holding the moderator temperature almost constant, mostly eliminating the positive reactivity coefficient from the moderator. I believe the coolant carbon dioxide had methane mixed in to help mitigate graphite erosion.
I refuse to engage in a battle of wits with an unarmed opponent [wikipedia.org].
(Score: 0) by Anonymous Coward on Wednesday May 03 2023, @12:51PM
Well maybe if China succeeds in building dozens of nuclear power stations AND no big problems occur despite inevitable earthquakes etc; then we could steal some ideas from China...
https://en.wikipedia.org/wiki/Nuclear_power_in_China# [wikipedia.org]
(Score: 2) by gnuman on Friday May 05 2023, @09:00PM (1 child)
There is nothing magical with those reactors. And they are useless for power generation anyway since they are not designed with safety in mind.
(Score: 2) by VLM on Saturday May 06 2023, @02:58PM
I think the fear, rational or otherwise, is something like lets save-a-buck by using the same upper primary cooling loop pipe, in fact here's a CAD drawing of the upper primary cooling loop pipe same as our subs use, now today's boogyman does an extensive finite analysis of the acoustic signature of the pipe resonance modes to determine their subs should see the resulting hyper detailed acoustic fingerprint, download that to their passive sonars, now they gain an extra two or three meters of detection range, which ain't much, but, rinse and repeat a dozen to hundred times, it could be an issue...