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China Tests a Supercritical CO2 Generator in Commercial Operation

"China recently placed a supercritical carbon dioxide power generator into commercial operation," writes CleanTechnica, "and the announcement was widely framed as a technological breakthrough."

The system, referred to as Chaotan One, is installed at a steel plant in Guizhou province in mountainous southwest China and is designed to recover industrial waste heat and convert it into electricity. Each unit is reported to be rated at roughly 15 MW, with public statements describing configurations totaling around 30 MW. Claimed efficiency improvements range from 20% to more than 30% higher heat to power conversion compared with conventional steam based waste heat recovery systems. These are big numbers, typical of claims for this type of generator, and they deserve serious attention.

China doing something first, however, has never been a reliable indicator that the thing will prove durable, economic, or widely replicable. China is large enough to try almost everything. It routinely builds first of a kind systems precisely because it can afford to learn by doing, discarding what does not work and scaling what does. This approach is often described inside China as crossing the river by feeling for stones. It produces valuable learning, but it also produces many dead ends. The question raised by the supercritical CO2 deployment is not whether China is capable of building it, but whether the technology is likely to hold up under real operating conditions for long enough to justify broad adoption.

A more skeptical reading is warranted because Western advocates of specific technologies routinely point to China's limited deployments as evidence that their preferred technologies are viable, when the scale of those deployments actually argues the opposite. China has built a single small modular reactor and a single experimental molten salt reactor, not fleets of them, despite having the capital, supply chains, and regulatory capacity to do so if they made economic sense... If small modular reactors or hydrogen transportation actually worked at scale and cost, China would already be building many more of them, and the fact that it is not should be taken seriously rather than pointing to very small numbers of trials compared to China's very large denominators...

What is notably absent from publicly available information is detailed disclosure of materials, operating margins, impurity controls, and maintenance assumptions. This is not unusual for early commercial deployments in China. It does mean that external observers cannot independently assess long term durability claims.



The article notes America's Energy Department funded a carbon dioxide turbine in Texas rated at roughly 10 MW electric that "reached initial power generation in 2024 after several years of construction and commissioning." But for both these efforts, the article warns that "early efficiency claims should be treated as provisional. A system that starts at 15 MW and delivers 13 MW after several years with rising maintenance costs is not a breakthrough. It is an expensive way to recover waste heat compared with mature steam based alternatives that already operate for decades with predictable degradation..."

"If both the Chinese and U.S. installations run for five years without significant reductions in performance and without high maintenance costs, I will be surprised. In that case, it would be worth revisiting this assessment and potentially changing my mind."


Thanks to long-time Slashdot reader cusco for sharing the article.

Read more of this story at Slashdot.

That Bell Labs 'Unix' Tape from 1974: From a Closet to Computing History

Remember that re-discovered computer tape with one of the earliest versions of Unix from the early 1970s? This week several local news outlets in Utah reported on the find, with KSL creating a video report with shots of the tape arriving at Silicon Valley's Computer History Museum, the closet where it was found, and even its handwritten label.

The Salt Lake Tribune reports that the closet where it was found also contained "old cords from unknown sources and mountains of papers that had been dumped from a former professor's file cabinet, including old drawings from his kids and saved plane ticket stubs." (Their report also includes a photo of the University of Utah team that found the tape — the University's Flux Research Group).

Professor Robert Ricci believes only 20 copies were ever produced of the version of Unix on that tape:

At the time, in the 1970s, Ricci estimates there would have been maybe two or three of those computers — called a PDP-11, or programmed data processor — in Utah that could have run UNIX V4, including the one at the U. Having that technology is part of why he believes the U. got a copy of the rare software. The other part was the distinguished computing faculty at the school.

The new UNIX operating system would've been announced at conferences in the early 1970s, and a U. professor at the time named Martin Newell frequently attended those because of his own recognized work in the field, Ricci said. In another box, stuffed in under manila envelopes, [researcher Aleks] Maricq found a 1974 letter written to Newell from Ken Thompson at Bell Labs that said as soon as "a new batch comes from the printers, I will send you the system." Ricci and Maricq are unsure if the software was ever used. They reached out to Newell, who is now 72 and retired, as well as some of his former students. None of them recalled actually running it through the PDP-11...

The late Jay Lepreau also worked at the U.'s computing department and created the Flux Research Group that Ricci, Maricq and [engineering research associate Jon] Duerig are now part of. Lepreau overlapped just barely with Newell's tenure. In 1978, Lepreau and a team at the U. worked with a group at the University of California, Berkeley. Together, they built their own clone of the UNIX operating system. They called it BSD, or Berkeley Standard Deviation. Steve Jobs, the former CEO of Apple, worked with BSD, too, and it influenced his work.
Ultimately, it was Lepreau who saved the 9-track tape with the UNIX system on it in his U. office. And he's why the university still has it today. "He seems to have found it and decided it was worth keeping," Ricci said...
The U. will also get the tape back from the museum. Maricq said it will likely be displayed in the university's new engineering building that's set to open in January 2027. That's why, the research associate said, he was cleaning out the storage room to begin with — to try to prepare for the move. He was mostly just excited to see the floor again. "I thought we'd find some old stuff, but I didn't think it'd be anything like this," he said. And Maricq still has boxes to go through, including more believed to be from Lepreau's office.


Local news station KMYU captured the thoughts of some of the University researchers who found the tape:


"When you see the very first beginnings of something, and you go from seed to sapling, that's what we saw here," [engineering research associate Jon] Duerig said. "We see this thing in the moment of flux. We see the signs of all the things changing — of all the things developing that we now see today."
Duerig also gave this comment to local news station KSL. "The coolest thing is that anybody, anywhere in the world can now access this, right? People can go on the internet archive and download the raw tape file and simulate running it," Duerig said. "People have posted browsable directory trees of the whole thing."
One of the museum's directors said the tape's recovery marked a big day for the museum "One of the things that was pretty exciting to us is that just that there is this huge community of people around the world who were excited to jump on the opportunity to look at this piece of history," Ricci said. "And it was really cool that we were able to share that."
Duerig said while there weren't many comments or footnotes from the programmers of that time, they did discovery more unexpected content having to do with Bell Labs on the tape. "There were survey results of them actually asking survey questions of their employees at these operator centers," he said.

Thanks to long-time Slashdot reader walterbyrd for sharing the news.

Read more of this story at Slashdot.

Matsumoto Illumination

artiegillispie has added a photo to the pool:

Matsumoto Illumination

Winter illumination of Matsumoto Castle

Alexanderplatz

Peter Kernwein posted a photo:

Alexanderplatz

Alexanderplatz

Peter Kernwein posted a photo:

Alexanderplatz

Alexanderplatz

Peter Kernwein posted a photo:

Alexanderplatz

Alexanderplatz

Peter Kernwein posted a photo:

Alexanderplatz

Alexanderplatz

Peter Kernwein posted a photo:

Alexanderplatz

Blue, green and white

Time Traveller2010 has added a photo to the pool:

Blue, green and white

Bremer Bay is a coastal town in Western Australia. Bremer Bay is well known for its beautiful beaches. I was really impressed by the colours- it seemed, the colours and the light changed every minute.

Extra journaals

Een moment van zelfreflectie: afgelopen week werd ik door twee verschillende talkshows gebeld of ik wellicht genegen was om iets te komen vertellen over het weer.

Voor Feyenoord-trainer Robin van Persie begint het nieuwe jaar zoals het vorige eindigde: met puntenverlies

Feyenoord verspeelt in de slotfase de winst in de uitwedstrijd tegen SC Heerenveen: 2-2. Van alle tegendoelpunten die de ploeg van coach Robin van Persie dit seizoen incasseerde, viel bijna de helft in het laatste kwartier.

thexiffy

Last.fm last recent tracks from thexiffy.

Red Hot Chili Peppers - Midnight

Red Hot Chili Peppers

The Stone Roses - This Is the One

The Stone Roses

Orac - Oracle

Orac

Black Mountain - No Satisfaction (Campfire version)

Black Mountain

Wel.nl

Minder lezen, Meer weten.

Dodental protesten Iran inmiddels boven de 500, meldt HRANA

WASHINGTON (ANP/RTR) - Het dodental door de jongste protesten in Iran tegen het streng islamitische regime en de slechte economische omstandigheden stijgt snel en is al ruim vijfhonderd. Dat meldt HRANA, een in de Verenigde Staten gevestigde organisatie die zich bezighoudt met de mensenrechten in Iran. Inmiddels zouden na twee weken onrust 490 betogers en 48 veiligheidsfunctionarissen om het leven zijn gekomen. Ook zouden ruim 10.000 mensen zijn gearresteerd.

HRANA baseert zich op informatie van activisten binnen en buiten Iran, waar het internet is geblokkeerd. Volgens Iraanse autoriteiten zijn bij de protesten zeker honderd politieagenten en veiligheidstroepen gedood. Zij melden niets over slachtoffers onder de demonstranten.

Het gaat om de grootste demonstraties sinds 2022. De Amerikaanse president Donald Trump heeft herhaaldelijk gedreigd in te grijpen als er geweld wordt gebruikt tegen demonstranten.


Code oranje om ijzel uitgebreid, ook waarschuwing in Zuid-Holland

DE BILT (ANP) - Ook in Zuid-Holland kan het in de nacht van zondag op maandag glad worden door ijzel. Het KNMI heeft ook voor die provincie code oranje afgegeven, die vanaf 23.00 uur ingaat. Eerder werd die waarschuwing al afgegeven voor alle andere provincies, behalve Zeeland.

Tijdens de maandagochtendspits geldt code oranje alleen nog in het noordoosten van het land, meldt het KNMI. In de rest van het land wordt het in de loop van de nacht en maandagochtend vrij snel minder glad.


Behance Featured Projects

The latest projects featured on the Behance

Season brochure, Nationale Opera & Ballet


Hallo "dit soort types" - u wordt genoemd

We staan er weer gekleurd (blauw) op. Dit weekend in de Omvolkskrant, door Robert van de Griend, chef schedelmeten alsook bekend van een BLOKSNOR. Kortom wederom Gelul van Crul, de hoogleraar Vooroorlogse Capitulatie die andermaal pleit dat die paar Nederlanders zonder migratie-achtergrond in de Randstad zich maar moeten aanpassen aan de nieuwkomiërs met 15 kinderen en dito luchtjes in de portieken. Benaming voor hoogleraar Crul komt uit dit Vintage TimonTopic uit 2023, en destijds was de omvolkskrant Trouw. En om helemaal on topic te blijven. Waar blijft die Leerstoel Na-oorlogse Remigratie? Wij wensen u een aangenaam etensmaal met spek erin.

Had u nog geen migratie-achtergrond? Zo moet het.


Rijnmond - Nieuws

Het laatste nieuws van vandaag over Rotterdam, Feyenoord, het verkeer en het weer in de regio Rijnmond

KNMI geeft nu ook code oranje af voor Zuid-Holland: 'Oppassen geblazen'

Voor de komende nacht heeft het KNMI voor alle provincies, waaronder Zuid-holland, code oranje afgegeven vanwege ijzel en gladheid. Volgens Rijmond weerman Ed Aldus is het "vanaf middernacht oppassen geblazen vanwege kans op ijzel".