Passwordstore is a great password manager, and I rely on it also in my Ansible playbooks, where it works by causing the gpg-agent to prompt me for the passphrase of my gpg key.

This prompt is a GUI prompt, which is very suitable when sitting at the computer in question. But a small annoyance is that it does not work at all when working on a remote computer via ssh (the prompt shows up on the remote computer's desktop, and the Ansible playbook in the terminal just freezes until it eventually fails).

It would be so much nicer if those ssh terminal sessions would instead get the gpg-agent prompt in the terminal. So far I have not found a method that achieves this without also sacrificing the GUI desktop prompt for non-remote work.

Desktop and laptop running Ubuntu 22.04 with i3wm desktop.
The relevant parts of my config can be seen in https://codeberg.org/ansible/dotfiles.

I considered the following related Q:s&A:s but did not achieve the desired outcome.

• https://unix.stackexchange.com/questions/554153/what-is-the-proper-configuration-for-gpg-ssh-and-gpg-agent-to-use-gpg-auth-sub
• https://stackoverflow.com/questions/17769831/how-to-make-gpg-prompt-for-passphrase-on-cli
• https://superuser.com/questions/1189602/how-to-configure-gpg2-to-ask-for-passphrase-on-the-console-instead-of-in-a-popup
• https://unix.stackexchange.com/questions/217737/pinentry-fails-with-gpg-agent-and-ssh

Some more tests

In the SSH session (no effect, unfortunately):

gpg-connect-agent updatestartuptty /bye

Learned that the gpg-agent is running in --supervised mode, and its ENV variables include DISPLAY=:0:

solarchemist@desktop:~
$ sudo cat /proc/2652288/environ
HOME=/home/solarchemist LANG=en_US.UTF-8 LC_TIME=sv_SE.UTF-8 LOGNAME=solarchemist
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/snap/bin
SHELL=/bin/bash SYSTEMD_EXEC_PID=2652288 USER=solarchemist
XDG_DATA_DIRS=/home/solarchemist/.local/share/flatpak/exports/share:/var/lib/flatpak/exports/share:/usr/local/share/:/usr/share/:/var/lib/snapd/desktop
XDG_RUNTIME_DIR=/run/user/1000 QT_ACCESSIBILITY=1
DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/1000/bus DISPLAY=:0 XAUTHORITY=/home/solarchemist/.Xauthority
MANAGERPID=1532 LISTEN_PID=2652288 LISTEN_FDS=4
LISTEN_FDNAMES=browser:extra:std:ssh INVOCATION_ID=<stuff> JOURNAL_STREAM=<stuff>

(the PID of the gpg-agent process is easily identified with ps aux | grep [g]pg).

Manual work-around

Manual work-around is to set pinentry-program /usr/bin/pinentry-tty in ~/.gnupg/gpg-agent.conf and reload the agent gpg-connect-agent reloadagent /bye.
To revert to the default (GUI) pinentry behaviour, just remove the line and reload the agent again.

• https://superuser.com/questions/520980/how-to-force-gpg-to-use-console-mode-pinentry-to-prompt-for-passwords

How could we go about to draw a straight line (vertical or horizontal) on top of any other window on our Linux desktop? I'm using i3 window manager with picom compositor at present, so I'm primarily interested in solutions that works for that.

I should get back to this question in the future and implement a nicer solution than pango-view

pango-view

Produces a vertical line (actually, more of a vertical box of limited width).
Very easy to make it, just issue the command in a terminal. pango-view was already installed.

$ pango-view --height=99999 --margin=1 --background=red -t ''

• https://forum.puppylinux.com/viewtopic.php?p=76743 relevant, very good and recent
• https://askubuntu.com/questions/328543/are-there-any-tools-for-drawing-on-the-desktop-drawing-over-apps
• gromit-mpx is a good over-app painter, but does not provide perfectly straight lines
• https://www.linuxfordevices.com/tutorials/linux/tools-to-draw-on-linux-screen

Using biblatex with a numeric style and a book class with frontmatter/mainmatter, would it be possible to have all citations in the frontmatter appear last in the list of references, as if the frontmatter (from biblatex's point of view) appeared after the mainmatter?

\documentclass{book}
\usepackage[utf8]{inputenc}

\usepackage[backend=biber,sorting=none,style=nature]{biblatex}
\usepackage{filecontents}
\begin{filecontents}{\jobname.bib}
@misc{hydrogen,
  author = {Author, A.},
  year = {2001},
  title = {Alpha}}
@misc{neodymium,
  author = {Luthor, Lex.},
  year = {2002},
  title = {Bravo}}
\end{filecontents}
\addbibresource{\jobname.bib}

\frontmatter
\cite{neodymium}

\mainmatter
\cite{hydrogen}

\backmatter
\printbibliography[title={List of references}]

\end{document}

In the above MWE, references in the "List of references" are printed in the same order as they were given in the document, so neodymium would be listed before hydrogen in the "List of references".
This also means that the citation in the frontmatter would be labelled [1] in the text and the first citation in the mainmatter would be labelled [2].
This is just as expected with the numeric style as often used in science and engineering theses.

I wonder if there is some way to make the first citation in the mainmatter be [1] (because it might be jarring for the reader to see the first citation in the first chapter be something like [11], it may make them wonder what they missed), without having a separate \printbibliography for the frontmatter (nor using refsection or refsegments, because I don't think they will help in this case). Preferably any citations in the frontmatter would simply be appended to the end of "List of references", as if the frontmatter was processed after the frontmatter by biblatex.

I think this would be hard to achieve. But I'd like to hear if anyone knows better?
Would something like this be possible? Have I missed something obvious?

I have read the Sorting section in the biblatex manual, and read these related (but not-very-pertinent) questions on TeX.SE

• https://tex.stackexchange.com/questions/540610/numbering-issue-in-printbiblography/540615
• https://tex.stackexchange.com/questions/306678/biblatex-have-two-separate-bibliographies-with-consecutive-numbering
• https://tex.stackexchange.com/questions/244150/citations-out-of-order-with-appendix-and-split-bibliographies-in-backmatter

Would it be possible to add a comment system to Shaarli posts?
It seems so.

• Add Disqus or Isso comments box on a permalink page [#181](https://links.solarchemist.se/./add-tag/181)
• also see Shaarli plugins, may be some ready-made solution out there.

Road vehicles

• The Hague is the first Dutch city with a taxi fleet running on H₂ (Toyota Mirai, specifically) (2020-04).
• As part of the European Commission's JIVE project, a dozen H₂ buses for Bolzano, Italy. The buses are manufactured by Solaris and have a range of 350 km on a single tank of LH2 (2019-07).
• FlixMobility (parent company of Flixbus) plans to operate fuel cell coaches on long-distance routes (2019-11). This as part of the research project HyFleet together with its partners Freudenberg Fuel Cell e-Power Systems and ZF Friedrichshafen AG, overseen by the German Federal Ministry of Transport and Digital Infrastructure, with start of commercial operation slated for 2024. More sources: 1.
• The first H₂-powered double decker buses have started operation in Aberdeen, UK (2021-02). The project was funded by the city, the EU, and the Scottish government, for 15 buses costing about 0.5 million GBP apiece.
• Gross-Gerau district in Germany plans for 80 H₂-powered buses in its fleet by 2028. I wonder how many buses the city operates in total.
• Hyundai plans to sell 1600 heavy trucks in Europe, and cooperates with Hydrospider for the H₂ supply.

Trains

• San Bernardino county in California awarded a contract for a H₂-powered train in 2019 to Stadler to run by 2024. I thought southern California was densely populated - why not electrify the tracks? Fuel cells are better than dirty and loud diesel locomotives, I suppose. This is the first H₂ fuel cell train in the US, and many other places in the US are quite sparsely populated, so let's hope it is followed by more.

Ships

• The Norwegian Public Roads Administration is to operate the world's first H₂-powered ferry connecting its fjords. The ship is built by Norled and has a carrying capacity 299 passengers and 80 cars. Details on its power train have not been forthcoming.
• A river vessel on the Rhone river with a powertrain built by ABB, supported by the European Commission's Fuel Cells and Hydrogen Joint Undertaking (FCH JU) and in cooperation with other parties.
• The first H₂-powered ferry in the US has started serving San Franscisco Bay. It takes 75 passengers, has three fuel cell stacks, and a top speed of 20 knots. The project was awarded a $3 million grant by the California Air Resources Board. For reference, there are about 1000 passenger ferrys operating in the United States.
• The world's first LH2 carrier has been put into service ferrying grey H₂ (meaning H₂ produced from fossil sources) from Australia to markets in Japan. The vessel was built by Kawasaki Heavy Industries and comes equipped with a tank able to hold 1250 m³ of liquified H₂ at a temperature of -253℃ (20 K).

Midsummer får 32 miljoner euro (ca 300 miljoner kronor) från EUs innovationsfond för att bygga en CIGS tunnfilmsfabrik om 200 MW i Sverige.

https://midsummer.se

I am heavily indebted to Hoger Gerhardt for posting his example on TeX.SE.

I chose to put a DOI symbol (thanks to the Academicons package) at the end of each bib entry. I think it looks rad.

\usepackage[backend=biber,date=year,doi=true,url=false,style=nature]{biblatex}
\usepackage{fontawesome5}
\usepackage{academicons}
\usepackage{hyperref}
\renewbibmacro*{finentry}{%
   \iffieldundef{doi}{%
      % Entry lacks DOI
      \iffieldundef{url}{%
         % Entry lacks URL and DOI
         \finentry%
      }{%
         % Entry has URL but lacks DOI
         % Show URL hyperlink as icon (concsiously not using same icon as our "external hyperlinks")
         \finentry\space%
         \href{\thefield{url}}{\footnotesize\faIcon{link}}%
      }%
   }{%
      % Entry has DOI \aiDoi
      \finentry\space%
      % lower the DOI  symbol a little to align better with baseline
      \href{https://doi.org/\thefield{doi}}{\raisebox{-0.1ex}{\aiDoi}}%
   }%
}%
% suppress output of DOI field (hide both DOI label and string)
\DeclareFieldFormat{doi}{}%

Here's an example of how the typeset bibliography entries look like (please excuse the poor resolution, the screenshotter suddenly decided to drop the quality):

Just heard about it. Adding this note to check back later and research who is backing it, etc. Looks worthwhile.

• https://github.com/dpgalliance
• https://exchange.dial.global/products (supported by Gates Foundation, SIDA, UKAID, et al.)

Digital public goods (DPG) that caught my eye:

• https://www.govdirectory.org

Will add more as I learn about them. I only care about FOSS projects.

LXD

See my Ansible role that installs and configures LXD and provisions LXC containers.

Docker

I have some experience with Docker containers. Prefer LXC if I have the choice.
I have written an Ansible playbook to setup containers with docker-compose as part of a as-yet not-public project for InvenioRDM.

Podman

No hands-on experience yet.

Singularity

Hm, interesting. Could it be better than Docker for sharing something like a thesis with "all batteries included", I wonder?

Singularity can convert Docker containers to Singularity, or can run containers directly from Docker Hub
https://blogs.oregonstate.edu/learningbydoing/2022/01/04/docker-and-singularity-containers-which-one-is-better/

• https://en.wikipedia.org/wiki/Singularity_(software)
• https://github.com/sylabs/singularity
• https://pmitev.github.io/UPPMAX-Singularity-workshop/

Sverige

• Map (maintained by the association of the Swedish Energy companies, aka "Energiföretagen") of Swedish green hydrogen projects as of 2024.
• In Älghult, Kronoberg county, Metacon and Uppvidinge Vätgas have launched a H₂ filling station connected to its own electrolyser powered by a dedicated wind turbine, making the station self-sufficient. No word on the technical details yet. (2023-09-01)
• 20 MW electrolyser in operation at Hofors mill, operated by Ovako and delivered by Hitachi Energy (formerly ABB, if I'm not mistaken). It seems to be getting its power from the grid, not any dedicated PV or wind plant. The produced hydrogen gas (3500 m³/h) is used to heat steel before rolling and also to fill fuel cell trucks. The project is the result of a collaboration between Ovako, Hitachi Energy, Volvo, H2 Green Steel, Nel Hydrogen and supported by the Swedish Energy Agency (2023-09-05).
• The world's first off-grid and public hydrogen refill station was installed in 2019 in Mariestad, Sweden. Electricity from a 250 kW PV array is used to run an electrolyser with the ability to produce 46 ton H₂ per year. The station has two storage tanks with a total capacity of 345 kg H₂ at 200 bar. Anyone can fill up their tank with H₂ at 700 bar at a cost of 90 SEK/kg, and the station itself required an investment of 30 million SEK, most of which was financed via grants (mostly from the EU). This refill station should soon be joined by others in Sweden under the "Nordic Hydrogen Corridor" banner. Technical know-how behind this project was provided by Nilsson Energi as well as researchers from Stockholm university, KTH, and Uppsala university. This project has been mentioned in other sources: 1, 2, 3, 4.
• Mariestad municipality (again), I suppose riding high after their success with the off-grid H₂ refill station with storage and PV, has set out to build a preschool that would be completely energy independent by having its own PV panels on the roof and a battery storage bank large enough to cover two days consumption, along with an electrolyser and H₂ storage tanks. The battery bank will even out daily energy peaks, and the stored H₂ is meant to cover electricity and heating during the less-than-sunny Nordic winter (by means of a fuel cell). More sources: 1, 2, 3, 4. The project ran into regulatory issues, but they were resolved, and the preschool including its off-grid-capable energy system was inaugurated in January 2022.
• A small-scale electrolyser in Umeå, Sweden (running off-grid, it seems) operated by Svevia (a government-owned corporation) and meant to supply two of their own fuel cell vehicles. The electrolyser was supplied by Oazer. At present, this is only the fourth such electrolyser in operation in Sweden.
• Spanish fertiliser company Grupo Fertiberia intends to build a 600 MW water electrolyser in the Luleå-Boden area by 2026 at the earliest, fed with renewable electricity from nearby hydropower and windpower. The produced H₂ will be used to synthesise NH₃ (1500 ton/day), which would in turn feed a new fertiliser plant (to the tune of half a million ton per year, would be Sweden's first and only; Sweden imports around 600 000 tonnes per year). Via InvestInNorrbotten (in Swedish), Grupo Fertiberia (PDF), and Cornucopia (in Swedish).
• Uppsala Vatten och Vattenfall ska bygga en station för vätgas-tankning av tunga fordon, stöds med 48 MSEK från Energimyndigheten.
• Uppsala Vatten får 2 miljoner SEK i EU-stöd för att planera vätgasproduktion. (Energinyheter.se)

Misr

The political and legal conditions for hydrogen projects in Egypt is improving.

• The Norwegian firm Scatec will build and operate a 100 MW PEM plant near Ain Sokhna producing green H₂ plant intended as feedstock for nearby green ammonia production in cooperation with Fertiglobe PLC. The electrolysis cells will be supplied by Plug Power, and local works by Orascom. (2021-10) This project may also involve MEP and Petrofac (it's unclear to me at the moment if this refers to the same ammonia plant, likely the case).
• Positively massive project, if implemented: 7000 km² of PV and/or wind turbines planned to feed 90 GW of electricity to generate H₂ from water. For comparison, that's an area equivalent to more than 175 Benban's and a nominal power capacity 45x the same. Via FuelCellsWorks and ArabNews. I'm not sure this is feasible, to be honest. I will wait for confirmation.

Europe

• The HOPE consortium plans to build the world's first offshore green hydrogen facility by 2026. The consortium consists of several European companies and is backed by the European Commission. The plan consists of wind power supplying a 10 MW electrolyser fed with treated ocean water and a H₂ pipeline back to shore.
• Uniper and other German companies area currently constructing a 30 MW electrolyser which will be the centre-piece of the Bad Lauchstädt Energy Park, an investment of over 200 million EUR. The hydrogen will supply the TotalEnergies Refinery Central Germany some distance away (the project includes building a pipeline). (2023-06)
• Danish power supplier Ørsted received DKK 35 million from the Danish Energy Agency to build a 2 MW electrolysis plant with attached H₂ storage in partnership with Everfuel Europe A/S, NEL Hydrogen A/S, GreenHydrogen A/S, DSV Panalpina A/S, Hydrogen Denmark and Energinet Elsystemansvar A/S. 600 kg H₂/day, or enough to power around 20 buses.
• Hydrospider operates the largest hydrogen electrolyser in Switzerland at Gösgen with a capacity of 2 MW powered by hydro, able to produce up to 300 ton of H₂ per year (enough for around 50 heavy trucks).
• Shell opens a 10 MW PEM electrolyser at its Rheinland oil refinery in Germany. The plant is slated to start operation in 2024 and produce up to 1300 ton of green H₂ per year. The plant, currently Europe's largest PEM green H₂ electrolyser, was funded by Shell in joint cooperation with the European Commission's Fuel Cells and Hydrogen Joint Undertaking (FCH JU) (2021-07).
• Nel Hydrogen Electrolyser, a division of the Norwegian company Nel ASA, is supplying Iberdrola 20 MW of PEM electrolysers for a green fertiliser project. Press release, SR Vetenskapsradion.
• Icelandic company Carbon Recycling International (CRI) produces methanol (CH₄) from CO₂ collected from a nearby geothermal power plant and from H₂ electrolysed from water using renewable generated electricity in a plant with a capacity of 5 million litres of CH₄/year situated on the outskirts of Reykjavik. Chinese carmaking company Geely (also owners of Volvo Cars) invested in CRI in 2015, and partnered to build what would be the world's largest CO₂-to-fuel factory somewhere in China, planned to recycle 160 000 tons of CO₂ emissions from steel plants every year.
• As part of the H2FUTURE project (a cooperation between Siemens, the Austrian power grid, and others and backed by the European Commission's FCH JU project) 6 MW of PEM electrolysers from Siemens will produce H₂ for steel production at the Voestalpine steel mill in Austria.

Japan

• Fukushima prefecture, Japan, aims to cover 100% of its energy demand with renewable sources by 2040, and towards that aim has built a 10 MW electrolyser that runs off a 20 MW photovoltaic park in cooperation with the National Institute of Advanced Industrial Science and Technology. The electrolyser has a rated capacity of 1200 m³/h H₂(g) (approximately 841 ton/year if my math is correct, assuming NTP). Via @S_Johan_Lindahl.

Asia

• A massive (planned) expansion of the Mohammed bin Rashid (MBR) solar park in the UAE brings it total capacity to over 4.5 GW, well on the way to the project's target of 5 GW by 2030. This latest addition cost (LCOE) 1.62 cents/kWh (USD). (2023-09-07)
  The solar park is apparently meant to include electrolysers too.

In related news

• https://www.pv-magazine.com/2023/07/04/the-hydrogen-stream-china-starts-worlds-biggest-solar-to-hydrogen-site
• https://www.pv-magazine.com/2023/04/18/the-hydrogen-stream-chinese-companies-push-for-hydrogen-transport/

Dagens forskning kräver ofta tekniskt avancerade metoder och verktyg. Det ställer höga krav på medarbetarnas kompetens. Trots behovet har det saknats karriärvägar i Sverige för individer som är intresserade av den teknik- och metodutveckling som krävs för att driva och utveckla framtidens forskningsinfrastrukturer. Men med start den 1 april 2023 finns en sådan karriärväg på KI – potentiellt den första i landet.

Därför har KI nu etablerat en ny karriärväg för medarbetare som är intresserade av tekniska och metodologiska aspekter av forskning. Två befattningar skapas: forskningsinfrastrukturspecialist och senior forskningsinfrastrukturspecialist. Anställningarna kan bli aktuella både inom centrala forskningsinfrastrukturer och i enskilda forskargrupper.

• Vetenskapsrådets kriterier för FAIR forskningsdata
• Vetenskapsrådet vägledning för implementering av kriterier för FAIR forskningsdata

Via Svensk nationell datatjänst (SND).

Also on FAIR:

• https://www.fairsfair.eu - Fostering Fair Data Practices in Europe

Solar Protocol is a web platform hosted across a network of solar-powered servers set up in different locations around the world. A solar-powered server is a computer that is powered by a solar panel and a small battery. Each server can only offer intermittent connectivity that is dependent on available sunshine, the length of day and local weather conditions. When connected as a network, the servers coordinate to serve a website from whichever of them is enjoying the most sunshine at the time.

Via Solarpunks.

Solarpunks were prescient when they asked (in 2012):

What would computing look like if it had to get its power from purely local and renewable sources? What is the potential of low-and-no-power computing and sensor networks?

I would like to have a PDF viewer that lets me click a button (or press a key) to move backwards in the PDF file's git history. In effect, git checkout <commit> file.pdf but automatically moving back in the commit history on each keypress.

Combined with something like the overview mode of pdfpc, that could make for a very efficient way to glance through the history of a PDF file, such as a thesis or a beamer presentation.

So far I have not found any PDF viewer software with something akin to that.
Maybe I should just open the PDF in VSCodium and use the built-in git support? Would that provide something similar?

Lemmy

• https://browse.feddit.de (search communities across all instances, seems to work better than the search built-in to Lemmy instances)
• https://join-lemmy.org/instances
• https://lemmyverse.net

Lemmy communities (think subreddits) are given in this format: !communityName@instanceName.
Since Lemmy is on the Fediverse, you can follow Lemmy communities (think subreddits) from Mastodon, just replace the ! by @, and you should find the account name.

Lemmy Android apps:

• https://join-lemmy.org/apps
• Jerboa, Android app made by Lemmy's developers [I could not figure out how to switch to another instance without logging in first]
• lemmur is listed on F-Droid, but on its Github page the app clearly states that it's no longer maintained.

I det här avsnittet samtalar Sofie Helgesson med Till Koglin, lektor och forskare vid Lunds tekniska högskola. Han är kulturgeografen som undervisar ingenjörsstudenter med ett fokus på rättvise- och maktaspekter, om cyklisten i ett trafiksystem som är fyllt av normer och hierarkier.

Direktlänk till mp3 (26 min)

Good video. RSS is the way to go.

• https://mastodon.social/@thelinuxEXP/110339557565162230
• https://codeberg.org/solarchemist

Yes, please.

Renewable Capacity Statistics 2023 released by the International Renewable Energy Agency (IRENA) confirms upward trend of renewables against declining new fossil fuel capacity.