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Comment Build trend doesn't support the option (Score 4, Informative) 68

Triple capacity in the next 25 years? Good luck, even with the $trillions those companies could in theory throw at it.

A quick look at OurWorldInData indicates that total capacity has gone from ~2,540 TWh in 2000 to ~2,700 in the 2020-2023 window (jagged but roughly flat). So, about a 6.3% increase over the last 25 years, globally. Now, in the next 25 years, they want to see a 300% increase, in deployment of systems that take on the order of 6-8 years each, globally (thanks Google). With a little over 400 plants operating (per Google, 2023) globally, that means a net build of ~1200 equivalent plants, not accounting for rebuilds or decomissionings. Then further, all those reactors need the associated transmission capability and grid capacity, wheresoever they may be built.

All of this build needs to involve fairly rare, specialized skill sets and fabrication capabilities, which would need to be expanded to handle the volume (and then, perhaps, be mothballed? Or would the pace continue afterwards?) -- and over 25 years, we're talking about people who are starting *today* being potentially ready for retirement at completion, so entire generations of skilled workforce being involved.

Can it be done? Potentially. Personnel,manufacturing, and materials availability becomes a concern, but those might be worked through. Realistically? Not even close.

Comment 5%? In 5 years? That's "on the rise"? (Score 1) 103

Statistics, and damned statistics.

Per the article, someone named "Moorhead" (and CNBC forgot to reference who that is!) is thinking of seeing "up to" 5% increase in feature phone sales, over the next 5 years. The article also indicates that HMD Global is selling "10s of thousands" such phones, in 2022.

So, first; 5% of 90000 (the highest "10s of thousands" number) would be less than 5000 additional phones.

Given some numbers about the American market; 97% of people have a cell phone. 12% are "non smart", the remainder smart. That means, on a population of about 335M, there are about 40M non-smart phones out there, and about 285M smart phones.
5000 incremental phones per month, presuming the 2022 increase isn't related to covid-delayed purchasing, if totally due to people switching off smartphones, would make all of a 1% dip in the relative smartphone ownership over the course of...about 570 months, by my math. Or, about 47 years.

Given the iPhone was first released in 2007, and calling that the first "smartphone" -- it's taken 15 years for smartphones to reach the ~85% saturation level. It'll take 3x that (or more) for feature phones to increase another 1% from the current level... and I'm ignoring population changes.

"up to" 5% growth in 5 years is... up to 1% per year, which is not efficiently off flatline, and generally below inflation levels. This doesn't smell like "on the rise" so much as "maybe falling slower" to me.

Comment Re:Wheat? (Score 2) 124

Interesting thought.
I can't begin to measure against the yield tonnes (precooked? cooked? hulled?) , but cooked, rice seems to be about 100Cal / 100grams, and wheat closer to 340/100grams (thanks again, google)

So, from a caloric view, even the ~50% lower yield by weight would seem to indicate a ~50% higher caloric yield for the wheat, per unit area being farmed.
With the earlier comment indicating that wheat is also a lower-carbon crop to farm, would seem to indicate a move towards wheat would be a good idea.

Comment Re:Wheat? (Score 4, Insightful) 124

Carbon footprint may not be the driving piece, or may depend on how you're measuring.

Low-tech farming (and, in fact, all farming) pays more attention to output per space (acre or hectare); on a quick set of searches, it looks like China, for instance, puts out about 7 tonnes of rice per hectare, or about 3.5 tonnes of wheat. Rice is therefore more efficient for the land use, which may be one of the drivers.

There are also challenges around space - rice needs water, and can be grown in tiered hilltops, but wheat prefers wide flatlands, for instance - that may drive interest in particular grains.

And all that ignores what the local consumers want, too...

Comment Re: Almost doesn't count. Need Another Seven Analy (Score 5, Informative) 53

Thanks for sharing this.

One key point in the video (4:45-4:52) notes that Dragon splashdown is at about.... 16mph. So both NASA and SpaceX seem to think that a splashdown landing at 16mph is valid.
Soyuz, which shares a parachute-based landing, has a landing zone area of about 25 miles in width. The same page notes that minimum speed under parachute is 24 feet per second... which translates to 16.4mph. Soyuz, with a hard landing (not water), has retrorockets to reduce speed further at the last moment; Dragon and Orion use the water to soften that landing.

Soyuz spends about 15 minutes under parachute; that's a 4-mile vertical travel window with zero horizontal control. In the video linked by bws111, Dragon was under main chutes for about 3 minutes prior to touchdown; about 0.8 mile vertical drop. With a crosswind of just 10 mph, Soyuz would have a ~2.5 mile variance in landing from the direct fall; Dragon would be down to about 0.5mile with the same crosswind.

Neither is remotely close to "pinpoint" landings, as seen with a glide-entry vehicle like the STS, the Dragon boosters, or what SpaceX is trying with Starship.

Orion apparently pops chutes at about 24000 feet, or about 4.5 miles up. That means accuracy from that stage can only be similar to Soyuz -- about 2.5miles with a 10mph crosswind -- and presumes that the capsule was dead on course at the moment the chutes opened.

Take into account that wind speeds at 24000 feet can routinely be 150+mph, typically decreasing with altitude. At 100mph average over the descent, we're now at a +/-25 mile radius from where the parachutes deploy to where the capsule comes to rest.

Suddenly a ~6mile radius as a target is actually really, really tight plotting, at least in my mind.

Comment Re:Why Investing is Fucked. (Score 1) 91

All true... I think my point is that there is nobody required to take the other side of my "bet". If I think a stock will go up, I buy some; if I think it will go down I can short sell; all I need is someone who is willing to sell or buy the stock at the given rate, either way. Their sale or purchase either starts or ends their own 'bet'; how they did isn't relevant to my own.

But, absolutely; the market as designed allows for 'bets' on both positions, for and against success of the company behind the stock.

Comment Re:Why Investing is Fucked. (Score 5, Informative) 91

Shorting stocks is an odd one, I'll grant.

Contrary to someone a couple posts up, one does not need anyone to take the other side of a bet; if I invest in a stock, expecting success, then I'm looking for the stock value to rise, and potentially for dividend income from ownership in the business. If my "bet" fails, then the stock value falls, and perhaps there is no (or not as much) dividend income. I "lost"; *nobody won because if it*.

For a short sell, as I've had it described to me; the "bet" is that the company's stock value will decline over a given period of time. So, as a short seller, I go to a existing shareholder, and write up an agreement; you (as the existing shareholder) let me sell your stock today, and in two weeks I'll give it back to you for today's value plus something. Meanwhile, since I sold it today for $X, I plan to buy it back next week for $X--. I use the difference as my gain (and to add the plus something to the loan of the stock).

So; sell a stock today for $100, buy it next week for $80 -- still have all the stock, plus $20. Give it back to the original person, add in their cut of $5 - I'm still up $15. That's a successful short sell. On a failure, sell this week for $100, buy back for $120 -- and still have to give the stock and an extra few bucks back to the original owner. Now out $20+; that's a failed short sell.

Short sells don't require that the company "fail"; only that the seller can take advantage of a (potentially short-term) decline in stock price by leveraging timely sell and buy orders.

Or put one more way; "classic" stock market is "buy low, sell high". "Short" selling is "sell high, then buy back low".

Comment Re:It's because a person can only (Score 3, Interesting) 149

The metric indeed.... number of houses or total quare footage built per employee.

One of the other changes over the last ~50 years? Death of the generalist construction worker. It takes several people to build a house, sure; but a great deal more people when each one employee has only one role - Framer, Roofer, electrician, drywaller, taper, mudder (yup, 3 people/roles for the drywall alone!), plumber, finish carpenter, window installer, painter, masonry, soffit/faschia installer... the list undoubtedly goes on.

A house might only have 2-5 people on site at a given time... but roll through over 40 different employees to finish the work.all the way from digging the foundation hole through final touchups.

A different metric would be to look at the person-hours involved per sqft, as compared over the timeline. Is the work "more" efficient (less person-hours)? Or has the multiplication of required job roles increased the total person-hour count required? In the first case, we might have situations where individual tradespeople are underutilized. In the second, we could be dealing with true productivity stagnation or loss (the workers in question, on average, can't do as much) or we could be looking at impacts of complexity or regulation increasing the total workload, as others have pointed out in these threads.

"Efficiency" is a funny number to work with, mathematically. Choosing what to measure efficiency against is almost more of an art than a science...

Comment Re:If I ever get an e-bike (Score 2) 141

I don't get why cyclists apparently can't be trusted not to ride at dangerous speeds on narrow paths in the town. Just... don't? My car isn't limited and I could do 200km/h around town, but just don't, because it would be very dangerous. Maybe they should get cops set up some speed traps and give out fines.

As an ebike owner... one of the tricky things with ebikes is that, if you pedal much (or ever use the throttle), they *will* take you up to their top speed, fairly easily (on the flat). For me, that means 32kph (~20MPH) -- holding to a lower speed requires a great deal of attention to (usually reducing) pedaling power, or changing the limiter settings. My ebike is legal (in Canada, in Ontario) for road work, but not in for some dedicated bike paths or parks, depending on the city. Limiting the maximum (powered) speed for the device simply makes it easier to confirm that the rider, not the device, is the one running too fast.

Other than making it less fun, the limits have very significant practical implications. In the EU the bikes are capped at 250W and it causes them to struggle significantly when going uphill, into headwind or just requiring higher speed on flat ground on shared roads.

Here, I'm 100% behind getting rid of this limit. Similarly, my 500W motor has a real challenge on heavy hills. Personally, I'd rather see a restriction around maximum powered acceleration (say, 0-max in 10 seconds) than on absolute power, to facilitate hilly riding. That said, I'm *not* in favour of increasing maximum powered speeds; 32kph already puts me well over the average cyclist's flat road speed, and bike helmets are not built to handle crash scenarios much faster. Classifying faster (powered) bikes as motorcycles or mopeds, with the inherent rule changes, makes sense to me.

Comment Re: 1,5 degrees since when? (Score 4, Informative) 49

Almost precisely.
From the article;

The greenhouse gases emitted by human activities have driven up average global temperature by about 1.2C to date...

There's a lovely webcomic by XKCD that shows the general timeline. Look for the swoop at the bottom... that's what the climate folks want to bend back closer to a straight line.

Comment Re:Profit and ecology align (Score 2) 217

...hold an entire continent power grid up...

Happens several times every year in most parts of the world. No doomsday needed.

I think this is where we differ.
Locally? Sure. One US state; one European country, or a couple of such, near each other. I'll totally agree here; happens regularly, particularly with smaller geographies. Again, the wider grid should help.
But *Continent wide*? That's the entire US, Canada, and Mexico, for mainland North America; or every country in Europe, simultaneously; or Russia, China, India, and a host of others for Asia, all having the same zero-wind, low-sun scenario. Far, far more likely that the south of France has power to feed north to Belgium; or that the Carolinas can feed to Vermont; or that India could feed power to part or all of China to reduce that battery load requirement.

Regions without an integrated grid? Yeah, they're going to need other sources. Texas, island nations like Cuba, and remote spots with insufficient hydro capability may well be using fossil fuels for a while, at least for their power backup requirements.

Probably doesn't help that I first read the 28 hours as *48*. Quite a climb down from that to 18, too...

Comment Re:Profit and ecology align (Score 1) 217

...build a gazillion batteries to hold an entire continent power grid up for 28 hours straight.

This is a rediculous requirement.

28 hours of *total contintenal* battery power? Absolutely not required, unless we're somehow worried about a scenario where the wind doesn't blow, and the sun is eclipsed, and there's no water flowing down power dams, more than a day straight across the entirety of the continent. In which case, by my estimation, problems with available electricity will be rather low on the list, as the Vogon fleet blocking the sun will be clearing us away for their hyperspace bypass anyway...

"Renewable" energy includes solar, wind, and hydropower. Hydro's convenient, if massive to build; once the dam is complete, one tends to expect it can produce at- or- near capacity unless the water level drops. The Hoover dam's a good example of that changing -- over the course of years, not days or hours -- but Niagara, as a counterexample, is being *expanded*. So there's a source of 24-hour power available, regardless of any short-range weather systems.

Solar is highly consistent. Every day, the sun comes up and shines; and, across the continent, large fractions of land receive direct open sunlight. Even in areas clouded on a particular day, solar still provides some fraction of the nominal load. Overbuilding resolves capacity requirements, and planning for overnight darkess is predictable.

Wind, also reasonably predictable. At the height of the commercial generators, and in locations where such generators are built, wind tends to blow most of the time, at a fairly steady pace, and all day. There will be times when the wind drops -- or goes too high -- but wind generation helps cover the solar overnight. Again, overbuilding - and building in multiple areas - tends to negate the low-generation windows for any specific area. If the wind stops in the southeast, it's probably blowing in the northeast... or southwest. Or both.

So, then -- what happens overnight on a still night? The grid! Power from the windy northeast can be redirected south to the storm-covered southeast, or west, or... and locallized battery installations can maintain power for a period, as well. This is exactly what already happens today, when a particular power plant is taken offline; the grid routes power from elsewhere.

28 hours of continent-wide battery capacity? Expensive and wasteful; the doomsday scenario where it could be 'needed' is irrelevantly unlikely.
~24 hours of *local* capacity, depending on the specific mix of readily available grid power sources? Might be reasonable.
12 hours? Fairly reasonable, for those overnight, still days. Though even there, the grid's likely to be able to compensate from somewhere, most of the time. And achievable using hyperlocal solutions, including local home batteries and vehicle-to-grid.

All of that, *and* reducing greenhouse gas emissions, while producing power at cheaper total cost. Yes, Coal and Gas plants will go away, eventually, at least for areas where the grid can compensate for localized changes in renewable power. Island nations and isolated communities, particularly in very remote areas like the far north, might need local, fossil-powered generation for a while longer, but continental grids like North America and Europe should certainly be capable of removing those power sources, given some time to continue building out renewable generation and storage capacity.

Comment Re:Won't matter anyway. SLS is a dead end. (Score 1) 71

I understand your thinking. So far, I'm not seeing it reflected in the planning - Starship HLS seems to be building on the same chassis, with massive (~100T) up- and down- mass capabilities from lunar orbit to surface.

That said, using a similar, full-build Starship as an earth-moon shuttle would also work -- if Starship is planned to be able to launch from here and make Mars, translunar seems straightforward - though fuel costs might be a question.

But I think either goes around the point of other comments, which arise from the overall SLS being overly expensive for the task. At $4.1B/launch, SLS gets one Orion vessel to the moon (and back). Starship (with Super Heavy), at the formally estimated $10M/launch - heck, let's use a 10x factor and say $100M/launch -- could put 41 Starships in lunar orbit for the same total outlay of funding. At that ratio, mass differentials and orbital transfer fuel requirements between Starship and Orion become irrelevantly small in the financial arithmetic of "cheaper" lunar landings.

A full Starship transit (Earth->Lunar Surface and return) will likely make a great deal of sense, if we're looking to colonize the surface. The cheaper launch costs, combined with greater payload per launch, would make SLS and Orion completely irrelevant for the purpose. For a small-crew science-only mission, Orion may indeed be a more efficient spacecraft to use -- if the launch costs weren't so high.

Or, so I see it at least!

Comment Re:Won't matter anyway. SLS is a dead end. (Score 1) 71

For manned trips to the moon there's little point taking Starship. You would need a lot of propellant to land it on the moon and lift off again. There aren't many missions planned that would need that kind of capacity on the surface.

You are aware that NASA has selected Starship as the planned lunar lander? Meaning Starship *is* the "lighter-weight craft" you're referring to for descent and return?

Comment Re: Wonder what (Score 2) 163

Check your data.
educationdata.org seems to indicate that per-student spending is $13,701 in K-12 schools, averaged across the country. New York State is the highest spender, at $24,881 -- still shy of this $29000 number. Utah the lowest at under $8K per student per year.

With an "Average" public school teacher salary of ~$65K, that means that each ~4.75 students pays for a whole teacher's salary.

Further, the average class size seems to be around 20 students, nationwide. So ~15 of those (or 3/4 of the spending) is *not* spent on teacher's salaries.

Put another way, 3/4 of what is spent per student, per year, does not go to teacher's union members - it goes to the administration, buildings, and other supplies required.

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