Posts by MachDiamond

US regulators set the stage for small, local nuclear power stations

Re: More lawyers

>Think building a whole estate of identical houses versus building a millionaires mansion.<

Building a whole bunch of homes doesn't often cause years of very expensive lawsuits. If the cost of a nuclear reactor was down to mostly the construction cost, you'd be right that building them in a factory would be the best move. The problem is that construction costs are less than 50%. There haven't been new designs put into commercial service as they center around fuel assembly availability. A design that needed new fuel configurations would need a plant that could make that fuel and there isn't the demand to build and operate that new fuel fabrication facility on a full time basis. It's another downside of continuing with the old way of doing nuclear reactors and a really good reason to be looking much harder at liquid fuel designs.

More lawyers

Why would building more reactors be simpler or cheaper? Each one of those would be subject to environmental assessments, anti-nuke protests, NIMBY lawsuits at the outset and more lawsuits for perceived injuries down the road after they've been built, etc, etc. The father of the Pressurized Water Reactor, Alvin Weinberg, was of the opinion that they weren't the best approach to take after further research into different types of reactors were theorized and work done on a few. We've been stuck with what we've always done because anything else is "unproven technology". The latest crop of computer processors was unproven just months ago. The same thing happens with everything from transportation to medical therapies.

The only reason I can see for zero progress building new reactors is the political election cycle. Anything proposed has to be completed within a 4-6 year timeframe from start to finish. This relegates anything new to the dust bin if it has a governmental aspect to it. It won't get any support unless it has the possibility of buying votes before the next election. For publicly traded companies, most things have to be done in 3 months or less so the quarterly report looks good when published to the stockholders (ie, the C-level execs). Gone are the days of a Bell Labs where the goal was to pursue novel new technologies on a continuous basis so there was a possibility of new products that aren't just a rehash of an old product.

If people are going to continue adding to the world population at an unsustainable rate, how and when power is used will have to change alongside how it's generated.

Re: @Dr Syntax - "more radioactive"

"if you leak a single radioactive particle from a nuclear power station you never hear the end of it.'

That's because the radio activity from the fly ash piles is NOR, naturally occurring radiation and we all know that natural things are good for you.

Re: @Dr Syntax - "more radioactive"

"we could build really big solar-thermal plants in desert areas"

That's been done at scale and it looks like it doesn't do very well. The big system on the California/Nevada border is offline and never met its promises. It did have the bad side effect of attracting and incinerating birds as the mirrors look much like a body of water from an angle. Other systems have faired pretty much the same.

Re: There is another explanation

"They're not great, and they're certainly not cheap. Hence our ever increasing energy costs."

Where do you go once you've banned the coal and nuclear power plants? That includes heaping on so many regulations and restrictions that they are effectively banned. Geothermal requires certain geography to be cost effective. Drilling tens of km to have enough delta T in some areas it too expensive up front. Just about every river that can can accommodate a dam has got them already. Dams aren't exactly ecologically benign and many groups are lobbying to have many removed.

So far, there doesn't seem to be a cheap and easy drop in replacement for coal/nuclear while still trying to support the same usage. Processes that are the most energy dependent may wind up being only viable in regions that can supply steady and large amounts of power. Cycling a refinery on and off isn't a good idea. Processing and refining metals is also something that would be hard to stop and start. Producing ammonia might be something that can tolerate intermittent production if it isn't entirely banned. It's a big user of electricity. More than many people might realize.

Re: @Dr Syntax - "more radioactive"

"You do realize that states have interconnected grids so on a day when the wind isn't blowing as much power can be imported from another state, right?"

Not always. I was just reading an article that was saying the issue wasn't with generation in a particular area, but interconnects being maxed out. The price per mile of transmission lines isn't cheap and it requires a whole bunch of environmental assessments and lawsuits to get done. The area is a hot spot for data centers and they can't put anymore in. I have no idea why all of these data centers have any need to all be in the same place to start with. The owners and sort of data they handled were pretty diverse.

"Plus, doesn't "more radioactive" equate to "is radioactive and dangerous for much less time"?"

Yes, but in a PWR, you don't just get one or the other, you get both.

Pull jet fuel from thin air? We can do that, say scientists

Re: Misled by the headline

>Thought it was going to be about planes that get fuel chemicals out of the air which they are flying through. Now that would indeed be difficult....<

An atmospheric ram-scoop? That would be truly amazing.

Re: Not Good News for global warming.

>Reductions in numbers of flights would, of course be a great help too.<

So if there were train routes and schedules that made sense for more people. there would be less of a need for air travel. With an electric train, a whole bunch of the av fuel from the air process chain wouldn't be needed. Generate power from the sun, cram into a train.

>Oh yes, I see. The first stage of my plan was to burn all the greens as a source of ecologically friendly power.<'

If you sell tickets, you'll cover the cost of the coal.

Re: What an achievement ... in hyperbole

>Same goes with the much touted hydrogen gas production through hydrolysis. As long we can be charging a BEV or something that's a more useful and efficient use of that energy than generating H2.<

If gas gets phased out and then banned, there will be more demand to use electricity to produce heat in homes. It's on my mind as my house uses propane. It would be difficult to make the changes to have an electric range, but if I can shift heating water to solar, an 8kg can of propane could last plenty long to not be much of a worry. Heating the house in the winter is already done with solar for the most part.

Re: What an achievement ... in hyperbole

"Hyperbole aside, this seems like an interesting starting point and there may well be something of value to come from it."

The danger is this sort of thing gets written up in the popular press where it's seen by some politician's staffer and all of a sudden some governments are pouring money down any rat hole that claims to be on the track to commercialize the "discovery". None of the politicians nor their staff usually have any training in anything but law. Rarely will you find any that understand science and engineering being rather deficient in the genes that let one do maths.

This is a curiosity way off the end of the graph. It might give some insight into a similar process that could turn out to be useful, but perhaps not. For the time being, it should be left in the university labs until somebody clever spots the improvements that need to be made. There are many things that are feasible to do now or are much better candidates for getting research grant money. Is it the mystique of flying that makes something like this a flame for all of the moths?

Re: At scale??? Yes, easily

>Similar for Uranium, there's an awful lot not being mined because the demand just isn't there.<

This happens a lot with elements and minerals that aren't in large demand. Cobalt gets a bad name when it's just another element that hasn't been in high demand so it's only sourced where it's most plentiful by people that don't have anything else to do to put food on the table. It's very useful in Li chemistry batteries and makes them even more valuable for recycling. Uranium was thought to be very scarce and the US was buying up all they could find during the time the Manhattan program was going so Germany would have a hard time getting any and the US could tie up all of the finds. After it wasn't so important to protect the secret of Uranium's potential, prospectors were finding it all over the place. Lithium is being found down old mines in Cornwall now that it's in high demand.

Re: At scale??? Yes, easily

>"Thorium reactors come up all the time, but no one seems to actually be able to build them."

<

The US had one running for a couple of years before the program was quashed by President Nixon and before the next iteration could be made that included continuous processing of the fuel. The Chinese paid a visit and picked up all of the plans and will hold the patents in another couple of years when they have a commercial system all worked out.

Re: David MacKay..a book that showed how "easy" that is "Sustainable energy without the hot air"

>My usage, and that of many others is that we use our car in the morning to go to work <

Obviously there has to be a way to place limits on how much power you are willing to sell back to the grid and at what price. While many places don't have options for charging an EV RIGHT NOW, there may be in the not too distant future.

There seem to be so many people that rage against EV's because they don't have off-street parking. I figured out long ago that I have no desire to live somewhere with housing that dense. I say "tough" you don't get an EV and that's that. Maybe it's time to take a look at why you live someplace where you are cheek by jowl with your neighbors. Are you happy living packed in like that or is there tension due to neighbors making more noise than you like? With the one exception of the neighbor in my area that has a military grade sound system, the only problems I have are with a certain ethnic group that holds the belief that their "music" needs to be heard and felt and cruise slowly through the city to share it with everybody.

Re: David MacKay..a book that showed how "easy" that is "Sustainable energy without the hot air"

>If we all have EV cars, then we can use their batteries for the night, ie, Vehicle to Grid. <

The problem with that is The Grid often can have a surplus of generation at night and demand is quite low. It's better to have lots of places to plug in a car and be able to transmit pricing down the line so when supply is abundant, an EV, home battery or other storage device can charge up at a lower cost. That might be in the middle of the day when a strong storm is pushing the wind turbines like mad off of the NW coast.

Re: At scale??? Yes, easily

>That means 1.2% of the Sahara desert is sufficient to cover all of the energy needs of the world in solar energy. <

Elon thinks that the US could be powered by just a corner of the state of Utah being covered with solar PV. It starts falling over when you find out the state isn't flat, the environmentalists would band together and have somebody with a thick neck track Elon down to have a short conversation with him and to install the HV transmission lines everywhere would take more energy to produce than all of those panels will put out in their lifetime.

I'm not against putting up some solar installations in the Sahara, but the power would need to be used locally. If that power can transform local raw materials into useful products, it might help the continent join the first world and shift some industries that require lots of energy such as Aluminum production from bauxite and ammonia production if there is a useable fresh water source that doesn't kill off a swath of people if it's used.

Re: only 4% efficient ?

With Starship ready for over 1,000 launches per day in just another month or two, we could build a Dyson Sphere and capture 100% of the sun's output so .........................

Re: Anyone got any more paper napkins?

>Given incident sunlight has about 1kw/m^2<

At the top of the atmosphere, but not at ground level. The figure gets used as a measuring point for solar PV because the math becomes so much easier.

Re: Chemical process

>No. The Siemens project uses solar power in Abu Dhabi to electrolyse water to make hydrogen which is then used through a number of steps to make the aviation fuel.<

The efficiency for that is likely scary low. I can see that sometimes even a very inefficient process is useful for a very niche application, but if you are looking for ways to mass produce transportation fuels, it's a dead end street.

Re: Chemical process

>Come to Australia - we have masses of useless sun-drenched desert that is ideal for this kid of thing.<

It still doesn't make sense. With the efficiency so low, it would be better to use that land for just about anything else after covering it with solar PV and concentrators for process heat.

>A very big, very wealthy industry sector will spend billions to bury this.<

Tin foil hat time. If something will make money, there will be some wealthy investors that will put money into it.

>Given a large area that you are willing to cover in solar something, you get several times better bang for your square metre if you just generate electricity.<

If you are dead set on covering the landscape in solar something, why not power rail cars? It doesn't have to be a system as dedicated as HSR since I haven't seen any implementations that could share the right of way with freight too. Rail isn't handy for crossing oceans, but it makes the most sense to work on the lowest hanging fruit first. If we wind up finding some way to replace aircraft powered with bog standard Jet-A as the last piece of the puzzle, that might not be so bad. In the mean time, electrically powered trains including some HSR might get more people out of the sky reducing the amount of petroleum fuel being used in planes.

>showed that if ever a safe autonomous electric vehicle could be made, cities would change dramatically. <

I have a few cupboards full of cookware that spends most of its time gathering dust. Should I get "cookware as a service"? If I planned my meals out a couple of weeks in advance, maybe it would work, but if I wanted to be spontaneous and cook something I found myself craving, I might be stuck.

The same thing might happen with "Car as a service". You decide that you'd much rather go out for a sit down dinner but discover that due to a sports event just letting out that all of the cars in the area are spoken for until late. Maybe you need to pick up your son from football practice, but your payment card has been cancelled due to somebody trying to make a fraudulent charge against it. The bank caught it so it won't cost you any money, but you won't have a new card delivered for 10 business days. In the mean time, it's raining and your son still needs to be picked up. The argument that most cars spend their life sitting around isn't a good argument. We aren't buying a car with an expectation that it will be used continuously. We own a car so it's ours to use when we need it. I own a car but I still would prefer to take the train to visit my mother for the day on a weekend. The train tickets are cheap and I've rarely had a delay. Taking the car is slightly faster on a good day and significantly slower when there's been an accident or it's hissing down with rain.

Flying is completely off the menu. Somehow I seem to be on that non-existent list and would be "randomly selected" for extra screening when I would fly to the point where I was sick to the teeth of being groped and having my bags completely tossed so I've sworn off entirely. Busses that stop every block take far too long and always feel like they will tip over when they go around a corner.

>If you need to change the line for whatever reason, you can't. If a service is no longer required, you can't repurpose the tracks. You're stuck with it.<

In the US, tracks are owned by the freight companies with passenger trains leasing access. If a passenger service is no longer needed, it's highly unlikely that the route is also going to lose freight as well. Given that passenger trains can be booked a couple of months in advance, more lines going to more places and more frequent service on existing routes would work out really well. I was looking at a trip last week and there were no rooms left, only coach seats. Coach doesn't come with meals or access to showers so it isn't that good for long trips. I also don't sleep well sitting up even though the seats recline quite a bit. It's too bad the trains don't still have the curtained cubby holes for sleeping anymore.

Many population centers got their start due to being serviced by a train. There are still the remnants of that left. I don't see that train routes going between major cities would ever wind up being cut.

Re: you focus on EVs were you can

>The problem is that in Britain (and the USA) there's no concurrent plan to improve public transport alongside it<

There is no rational plan, but there will be plans of some kind. Las Vegas is a popular weekend destination for people in Southern California. Train service would alleviate all of the traffic problems and get rid of the massive tailbacks when there is an accident. The problem is as soon as there is talk about adding train service again, some attorney makes it a requirement that it will be High Speed Rail and that kills it. The project gets trimmed back to a route that doesn't get anywhere near Los Angeles or San Diego so people will just make the whole trip in their car rather than park up in some small desert town along the highway and hope their vehicle will be there when they get back while at the same time only minimally shortening their trip time.

There are also those projects that fall short of being a complete solution. Going back to Las Vegas, Elon carved out a couple of sewer pipes under the convention center and instead of going with a system like the one at Heathrow terminal 5 with automated cars, they are using human driven off the shelf Tesla vehicles where I haven't seen a demonstration of whether the passenger doors could be opened enough to get out if there were a problem. The UltraPRT pods at terminal 5 doors open like a barn door so don't need the same clearance as a gull-wing or standard car door. Only half of a proper transportation system was worked out and the rest just bodged.

Sleepy Joe Biden's office has put forward an allocation for Amtrak, the US's national passenger rail service, to expand it a bit. One of its big problems is the lack of destinations and not much of a schedule. They also don't have the amount of rolling stock they can use and even less now as there was an accident when a train hit a dump truck that stalled at a level crossing. I believe that train service is one of those things that lends itself to "build it and they will come". It's a great way to travel without all of the indignities of going by air. Schedules that connect points with overnight service might not even need to travel all that fast. I love that I can take luggage without yet another fee and get a meal of my choosing or a drink if I want from when I board to the end of my trip.

Re: The plan for the combustion fleet isn't to ban them from the roads

"That's *because* of cars - the cars are the problem, not the solution."

If it were only that simple. I'd love to take the local bus to the train stations some miles away when I want to visit my mom on a weekend since parking at the train station overnight would cost several thousand dollars in car repairs if the car didn't just go missing. The problem is that the bus isn't on a schedule that meshes with the train schedule. There is also no bus in the evening that would bring me home. We don't have public transportation that is thought of as a whole system. Every mode is considered, routed and scheduled in it's own little world.

Anybody with kids knows that having a car is a requirement in this day and age. They need dropping off and picking up from all sorts of programs. I don't get the whole idea of a school run as I walked to school or rode a bike when I was young. When I got my license, I drove myself and my best friend (or he drove) as the school was a bit further away and the gross tonnage of gear we had to schlep back and forth became burdensome. I don't think any parent wants to be trying to find a way to get their child to hospital in the middle of the night when the busses have stopped running. While that might never be necessary, it is a big fear.

US-funded breakthrough battery tech just simply handed over to China

"AT&T might have demonstrated the point contact transistor first, but the technology we actually use is based on the thick film transistor Philips demonstrated a few weeks later and that was in widespread use whilst AT&T were still trying to get workable yields on the point contact design (let alone generally consistent devices)"

Anybody that works at the forefront of science and engineering knows that these thing emerge when it's their time to emerge. This often means that it can look like an invention or discovery was made in different places only separated by days. A good read that shows a bunch of example is "The Making of the Atomic Bomb" by Richard Rhodes. The same concept is a key point in "Raising Steam" by Terry Pratchett and is also mentioned in "Outland" by Dennis E. Taylor. There are also many stories that stem from the race to discover all of the elements suggested by Mendeleev's Periodic Table.

Re: Sounds familar

"He has been pretty ruthlessly focussed on a single long term aim,

hahahahahahahahahaha. Elon focussed? Ever seen a graph on his Twitter usage. He flits from one thing to the next faster than a small rodent on meth.

Bloke robbed of $800,000 in cryptocurrency by fake wallet app wants payback from Google

What was the point

Why did this person have a burning need to buy and store $800,000 of real money in a manner to obfuscate its comings and goings? Was it some belief that digital Leprechauns would wave their willies at it and it would grow? Did this person want to make some dodgy purchases? Being on the cutting edge can often mean getting bits sliced off.

There is no way that Google can completely test every app that gets posted to the App Store. The most they can do is conduct some minimal checks that what's being posted looks like it comes from an identified source. If somebody complains, perhaps they can have a look to see if there's something untoward going on, but too many times reports are just malicious attacks from competitors. Just look at YouTube. If Google took down everything that had a complaint lodged against it, there would be little point in having the marketplace at all. Not that I get anything through them and I'm dismayed by the lack of being able to directly download software from the manufacturer. iOS is even worse.

Virgin Galactic delays commercial suborbital flights again

"I can not help to wonder what was the actual status of the rocket that launched the first flight?"

The first spaceship was lost in an accident that killed the co-pilot and severely injured the pilot. The status is it's in a big load of pieces somewhere if it hasn't been disposed of.

Re: How far could the flight get?

"I understand that they leave and return to New Mexico, with a flight time of 2.5 hours. If, instead, they landed somewhere else, how far would they get?"

Most of the time is getting the stack to the release altitude. From drop to landing is a very short period of time spent going moderately straight up and then down again. If distance was the goal, the spaceship might go a pretty considerable distance if flying horizontally didn't overspeed the airframe. The mothership would still need to fly to meet it again to take it home for a new fuel grain and a fresh dose of nitrous oxide. It's really a one-trick pony. Point to point travel isn't something it would be very good at.

Amazon buys Roomba maker iRobot for $1.7b

The unstated reason for buying iRobot scares me

I've never owned a Roomba, but I think they are very clever. The problem I have with them is I'd still need my standard vacuum to get the corners, stairs, etc. The Roomba only gets the easy to get to main patches of floor which are the fastest bits to do with the upright (it's even an actual Hoover). The more time consuming parts of the process is moving chairs, picking up things and shifting trash bins. A Roomba won't do any of that so I don't see how it's saving me any time cleaning.

The big question is why would Amazon be interested in spending a very large sum of money to get into the floor cleaning business. It has to have the potential of a very large payoff. How would they improve the product? Would it get an array of microphones that will relay to an Alexa? I'm sure their marketing could put a good spin on that. A camera is super obvious. Not only would it map the floor, it could assemble a 3D map of what's in the room as well and make assumptions about what it sees that can be inserted into a simulated view. How about if it could talk with baby monitors and other CCTV cameras looking from a higher perspective and uses the Roomba as a beacon for calibration since the image from a wide angle lens makes for lots of distortion. The cherry on the cake might be a sensor that samples the air exhaust of the vacuum cleaner for various substances. I don't believe I've come across a self-installed spy package that uses smell as an input, but it could be very telling.

Anybody that's worked on reverse engineering projects knows that every clue helps. Spies don't just think they'll find a damning piece of writing when they have a rummage through the contents of a dust bin. They will be able to put together a surprisingly accurate picture of the sort of people that use that rubbish bin. Just somebody's food preferences over a period of time can give away their national origin. Many religious observances have preferences or prohibitions around food even if only during specific times. Many of today's mega companies not only sell a product or service, but sell their users/customers information as a product. The more complete a picture they can paint, the more money the data is worth.

>Sometimes quite accurately but often I struggle to reconcile its drawn map with my floor layout.<

Joke's on you. The map isn't for you to use. bwahahahahaha.

The US grid is ready for 100% renewables, says DoE

No reports.

I have yet to see that grid operators have been diligently working on doing exhaustive analysis to see if there will be any issues with removing large centrally located power plants with many smaller and variable inputs at random nodes. That bit South Australia in the buttocks and did a lot of damage.

If you've seen anything, please post a link.

"No, that's because they aren't shutting down nuclear plants, coal-fired plants, or gas-fired plants yet. In other words, she said absolutely nothing."

You must be from out of town. All of those things are happening. There are even some unintended consequences stemming from new regulations that will go into effect in a few years regarding coal power plants. Some of those operators are retiring the plants early as they hit the point of heavy maintenance since they won't be able to operate them long enough afterwards before they'd have to be upgraded to meet the new regulations and they are approaching EOL anyway. If they don't do the maintenance, the plants might not comply with existing regulations so it's not possible for the companies to just run them until the wheels fall off. It's making a few politicians look like the bad guys as warnings are already being sent out to large customers that there may be no way to serve their needs past a certain date. That's often going to mean a large employer shutting down and moving or just shifting production to someplace like Mexico where a "small payment" can smooth over emissions irregularities at the local power plant.

veti,

All good points. Where will the battery cells come from for all of these grid level storage battery packs? Where will all of the raw materials come from before that? EV makers such as Ford are already under productions constraints due to limits in securing battery cells. Battery back up on a grid scale is also monstrously expensive.

The military isn't going to be zero carbon, ever. The vehicles they drive around on bases right now just to move one or two people from A to B are fuel wasters. You'd think they'd at least have a fleet of hybrids by this point.

The city I live in has a bunch of F-150 pickups that get driven around by works supervisors that don't have a need to haul tools or materials. The code enforcement witch trundles around in a giant SUV although at her size, a stout vehicle is necessary. The PD just bought several new SUV's although they did get V6 hybrids this time around. The surplus military troop carrier makes up the difference in fuel usage although they don't seem to drive it around much anymore with how fuel prices have shot up. It's not the sort of town where heavy artillery is needed.

Bad news, older tech workers: Job advert language works against you

Re: This news

"being able to see through the bullshit the PHBs come up with every day to try and justify their own employment/existence."

We also don't "request days off" and instead just send an FYI.

"no staying power at the company party..."

By preference I'd rather have the best excuse to not be staying at the company party for very long. By the time midnight rolls around, pickings are bleak (discovered the following morning. At the time they are perfectly acceptable.)

Re: We don't get to chose the language...

"He was obsessed that you needed a Master's in order to get out of bed this morning."

I can recall a job posting for a sale position selling an audio amplifier module targeted to be embedded in other maker's products where they wanted somebody with a PhD. For a sales job!

Re: We don't get to chose the language...

"and the people who insist on using them, are Absolutely Fucking Useless."

That last part is usually just abbreviated "H.R."

Re: We don't get to chose the language...

"I spend a week or two talking to the rest of the team, and some related teams we work closely with and come up with a careful description of what the job will entail,"

What kind of weirdo are you? Nobody does that! All of the important work is done choosing the biz buzz words that will go in the blurb about how awesome the company is. /s

Re: Not noticed it an ads, but have been told to my face in an interview

"came up with an entirely new app covering a massive hole in our customer needs, all using the latest tech, which has now become a major focus of our company."

Having lots of experience doing the work can be a bigger qualification than using the latest tools. Many times I find that one software package I'm being supplied with or told to use is so similar to one I'm already pretty good at that learning the new one is less than a week. The skill is more in knowing how to approach a problem than learning a new CAD program to make the pretty pictures.

Re: Anon CVs

"No, no, what IT training have you *received*?

Well, none actually.

Have you got any qualifications?

Well, BSc: Bronze Swimming certificate. ;)"

Excellent. The positioned is salaried and starts at 50% of the local cost of living if you aren't still living at home with your parents and they feed you as well. We like to see our "associates" commit to at least 60 hours of office time per week and to be willing to be on call the rest of the time with any communications being responded to within 15 minutes. You will need to supply a "high end" laptop and a reliable dual sim mobile phone with service provided by two independent companies so if one is down, we can reach you on the back up.

Re: Anon CVs

"Sometimes there's a competitive need to be somewhat vague about certain things but not always."

Too often that's what companies think when thinking is not something they do very well at. If there is truly a need to not publicize positions needing to be filled as it's a new direction for a large company, something like Apple looking at making cars, it could make more sense to work with a recruiter that's under an NDA that boldly states their body will never be found if they leak the info. Otherwise, it's easy enough to write a fairly generic job description that covers most of the needed requirements of the job but leaves off a couple of crucial bits that might give away too much.

Re: Anon CVs

"I understand that you're probably writing to a dozen companies a day and just want to be efficient. "

That can translate to somebody that just looking for any job, not a really good fit and could bail at a cough. The best candidates will be the ones that put some effort into finding out about the company they are applying to and not just going by the marketing drivel that was posted with the job listing.

Re: Anon CVs

"I will always let the candidate decide whether they're overqualified or not. "

That's a good idea. The person might be overqualified but is applying due to reasons you may not know or are allowed to ask. It will be good to get them into an interview and see if those reasons surface. An older worker may want to live in the area to be close to family such as grandchildren and the job is something that pays enough and won't be super stressful given their background. They could also be taking part in looking after somebody and doesn't want a "fast-paced, dynamic job" that usually means lots of unpaid overtime. Even if they are just looking at the job as something to tie them over for a period of time, if you know that going in, you may be able to leverage their qualifications and plan to bring somebody else onboard later. They might be just the person to streamline a department and build a better workflow for the next person to slide into and don't need to be there for the next ten years to be worthwhile.

Re: Anon CVs

"That sounds more like a cover letter for a CV than a CV."

True and many companies don't want to see a cover letter anymore.

"So it is fine to offer a non existing job and waste the time and effort people looking for a job put into applying if it is done in the name of science?"

Companies do this all of the time. It's a way to keep an eye out for people that they might hire even if they don't need to fill a position. Some job listings are aimed at just one person or a very short list as a way to get around non-poaching agreements. If you leave a company to start your own, your employment contract may forbid you from making offers to colleagues to join you, but you can post a job with such specific requirements that the people you want to bring along will be some of the only ones that fit the bill, you might be able to stave off a lawsuit. You will want to talk with an attorney first if you decide to tread that path.

"Large companies are probably looking at the future pensions liabilities of an ageing workforce who may have been with the same company since leaving education."

Pensions these days might be a big trap to avoid. I'd rather just manage that money myself. Beyond using it to buy and pay off a home (which I've done) and be in position to pay cash for things and avoid spending lots of money on interest, there are many more ways to save for retirement. Each has its own advantages. I don't like anything that has big restrictions on it. Life can have all sorts of bumps and change is a constant.