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Utforska den biologiska mångfalden!
Här samlar och presenterar vi vår och andras kunskap om djur och natur. Vi arbetar på att beskriva de cirka 60 000 arterna som finns i Norden och Baltikum.
Presentationen på denna sajt är dock ganska torr. Många sidor saknar beskrivning. Länkar för all del till Wikipedia och andra sajter.
En mycket mer visuell presentation av "livets träd" är den på OneZoom.
En annan (sidindelad som Naturforskaren men med mer visuella element) är Tree of Life web project.
On the political arena, the Egyptian government has established a "National Council for Green Hydrogen and its Derivatives", chaired by the prime minister and counting among its members: the minister of electricity and renewable energy, the minister of petroleum and mineral resources, the minister of justice, the minister of planning and economic development, the minister of finance, the minister of environment, the minister of housing, the minister of utilities and urban communities, the minister of transportation, the minister of trade and industry, the minister of irrigation, the minister of state for military production, the chairman of the Suez canal authority, the chairman of the general authority for the Suez canal economic zone, the first assistant to the prime minister, the CEO of the general authority for investment and free zones, and the executive director of Egypt's Sovereign Fund.
I must admit I wonder what the point is forming a special council if it includes what appears to be most of the government. No word on permanent members from industry or academia.
On the council's first meeting an executive committee was formed (unclear who its members are) and tasked with speeding up the approval process for green hydrogen projects and to entice companies to invest in such projects, using investment incentives such as 33%–55% less tax, and exempting most equipment and supplies from VAT tax, an exemption from real estate tax on buildings, and waived fees for registering the companies in Egypt.
To date, the government has signed memoranda of understanding (MoU) with among others ACWA Power (Saudi Arabia), Benchmark Alliance (?), China Energy company, the national holding company for chemical industries (the Egyptian one, I assume), DAI global company (Germany), OCIOR Energy company (India), Voltalia-TAQA alliance (sounds Italian?), and British Petroleum.
The stated ambition of the government is to produce green hydrogen at 1.7 USD/kg by 2050 and to capture 8% of the global market. The government expects that total foreign investment into green hydrogen projects to reach 81 billion USD by 2035.
The national strategy for green hydrogen is yet to be published, as far as I can tell.
Sverige
- In Tomteboda, Stockholm's largest PV roof-mounted plant, produces 400 MWh per year (1465 PV panels covering an area of 4000 m²). Co-owned by Areim and Blackstone and operated by Obligo Real Estate. (2021)
- The largest solar power plant in Sweden is built by a home-owner's co-op (HSB Södermanland) in cooperation with the energy company Energiengagemang. 41600 PV panels with a total power of 14 MW.
- In Morgongåva (40 km west of Uppsala) the logistics center of online pharmacy Apotea features Sweden's largest roof-mounted PV array with a capacity of 2.3 MW, enough to supply the building's entire annual electricity demand. Built by Solkompaniet. SVT.
- The ports of Stockholm and the port of Södertälje together have almost 4 GW of solar PV panels, and have plans for more.
Misr
- Benban solar park in southern Egypt is one of the world's largest PV plants, covers an area of 37 km² and has a power generation capacity of 1.65 GW (given the site's insolation expected to yield 3.8 TWh per year).
- In Kom Ombo, Egypt's largest privately-owned solar PV plant is expected to start commercial operation in January 2024. ACWA Power (Saudi Arabia) owns and operates the 200 MW utility-scale plant.
Europe
- Uniper (the recently nationalised German energy company) plans two PV plants near existing industrial sites in Wilhelmshaven (300 MW + 17 MW).
- Belgium's first floating PV plant. On a man-made lake on a site owned by Sibelco, a raw material producer.
- Spanish energy company Iberdrola commissioned a 500 MW solar PV park at Núñez de Balboa in the western Spanish region of Extremadura. At the time Europe's largest PV plant, as seen by NASA's Earth Observatory. The project cost €300 million and is made of 1.43 million PV panels. Via @S_Johan_Lindahl.
Asia
- Oman seems to be on a roll. Their governmental energy company Hydrom (recently created to spearhead their green energy transition) is planning a massive green hydrogen project with a capacity to produce 750 kiloton/year (if I understand correctly). 1, 2.
- In Qinghai province, China, a 2.2 GW solar PV plant was connected to the grid in 2020 (at the time the world's largest solar plant).
Americas
- In the five first months of 2023 the United States power sector saw more electricity generation from wind and solar (combined) than from coal for the first time ever. Many other countries have already passed this particular milestone (or phased out coal entirely), so welcome to the club, yankees, and keep it up.
Oceania
- In southern Australia, a 4 MW concentrating PV plant combined with 50 MWh thermal storage for almost round-the-clock power generation is now in operation. The Carwarp power plant is run by RayGen. The site uses triple-junction GaAs solar modules with almost 38% efficiency paired with water-based thermal energy storage. Each tower (there is four of them) has just over 4 m² of photoactive area producing 1 MW of electricity and 2 MW of heat (ΔT=90℃).
- 10 GW of solar power in Australia for Singapore.
- The largest PV plant in New Zealand sits atop a wastewater pond.
- The Nauru Solar Power Development Project - Battery Energy Storage System is a 6 MW solar plant and a 2.5 MWh battery storage system that will increase the share of renewable electricity in Nauru from 3% to 47% (like many other Pacific islands, Nauru relies almost entirely on diesel generators for power), which is expected to fully cover the island nation's current daytime electricity needs.
In related news
- A look at the major floating solar energy farms across the world, NS Energy Business magazine (2019).
- The UK has designated a project to build a 3800 km undersea cable from Morocco as having "national significance". The project is owned by Xlinks. (2023-10-01)
- The government of Egypt is set on building a subsea cable to Greece to sell solar and wind power to Europe. The GREGY interconnector would be 1400 km long and able to transmit 3000 MW. I wonder if power transmission would be strictly uni-directional or if it is meant to also allow power export to Egypt? (2023-09-30)
Feels like I keep hearing about new FOSS tools and services interfacing with Mastodon every day.
I need some place to keep track of them.
- https://github.com/toelke/mastodon2rss - Serve your mastodon home feed to RSS (including boosts!)
This is an academic seminar, so not much razzle-dazzle, but the subject matter is certainly cool!
Space-based solar power is the idea to put PV panels on satellites in orbit and beam the power down to the surface.
Do you think that sounds outlandish? Well, there is nothing technical stopping us - just a matter of financing and politics. Not like fusion which is still an unsolved problem. In my book space-based solar would be smarter, cheaper, and more sustainable than even nuclear power.
I have archived a copy of the seminar recording on my Nextcloud (in case you have any problems using the Zoom-provided recording).
- Due to rules severely limiting the allowed sulfur content in fossil fuels for (see, acid rain) over 80% of all sulfur produced globally is a side-product of fossil oil and fossil gas refinement. Unless we find another way to produce sulfur (sulfuric acid is a critical industrial feedstock), the change to renewables could seriously hamper our access to sulfur. Maslin & Day, The Conversation (2022).
- Shell got a lot of good PR a few years ago on the back of news that they would install hydrogen filling stations across California in cooperation with Toyota. Now they have announced their complete withdrawal from light-duty (read: private cars) hydrogen filling stations in the state.
Sounds interesting, but unfortunately the Encyclopedia website appears to be broken.
I sent a question to their webmaster through their contact form.
For the individual owning the car, It is very high. When we take the societal costs into consideration, it is even higher.
- This paper by Gössling et al. in Ecological Economics, 2022 was really eye-opening. Over 50 years, the total lifetime cost of ownership of a "cheap" car will reach 600,000 EUR, out of which almost a third is effectively a subsidy from society to the car's owner. If you are considering owning your own car, I strongly recommend to at least skim this paper (CC license, HTML and PDF freely available).
- Another paper (Mattioli et al., Energy Research & Social Science, 2020), this is one is a review that considers our car dependence from a systems of provision approach. Quite interesting if you want to learn more about the of the political-economic underpinnings of car dependence (CC license, HTML and PDF freely available).
The Gössling paper generated some news items across the web, for example
- Kea Wilson, StreetsBlog USA, 2022. Takes an American perspective, which mainly means that everything gets worse.
- Carlton Reid, Forbes, 2022. Again, puts an American perspective on the numbers, but correctly states that "cars suck more cash than most people imagine".
I also remember a Youtuber doing a nice video on the Gössling paper, but I cannot recall enough about it to find it at the moment. Maybe I will find it later.
When writing in R Markdown format I often would like to comment out one or more lines of text (for example to quickly test variations on sentences or paragraphs) in a way that these comments do not show in the generated HTML file.
The R Markdown Cookbook only mentions HTML comment syntax <!-- your comment -->
which does not stop the comment from remaining in the generated HTML file.
Best solutions, as far as I know:
Additional YAML blocks
Add a YAML block with commented out lines (baptiste's suggestion):
Some text in the document.
---
# commented out text
# and such
---
This works fine, it is just slightly verbose to use.
But it is the only option that works without any issues.
Abuse the markdown link labels syntax
This is the most popular answer (by far) on SO:
Some text in the document.
[//]: # (commented out text)
[//]: # (another comment)
According to other answers/comments, this sort of comment line should always have a blank line before it to be proper.
The drawback for Rmd appears as soon as we have more than one such comment line; knitr spits out a very visible warning in the standard output:
[WARNING] Duplicate link reference '[//]' at ... line ...
.
The only(?) way to avoid those warnings is to differentiate the link labels, but that quickly becomes tedious.
Some text in the document.
[//1]: # (commented out text)
[//2]: # (another comment, now without a knitr warning)
If you know of a less verbose method than adding YAML blocks, or an easier way to circumvent the knitr warnings, I would love to learn about it.
Kartläggningen ger en bild av nuläget i 200 tätorter med fler än 5000 invånare. Boverket refererar till den allt oftare uppmärksammade 3-30-300-regeln, det vill säga att man ska kunna se tre träd från sitt fönster, att 30 procent av stadsdelen ska vara täckt av träd och att de boende ska ha max 300 meter till ett grönområde.
Via Arkitekten.se
Art courtesy of blog.akhbarak.net.
The post title is the translation of the meaning of verse 5 of chapter 42 (Ash-Shuraa) of the Holy Quran.
A nice series of lectures from MIT on the 20th century history of physics (Maxwell's equations, light quantisation, etc.) by David Kaiser. Recorded in fall 2020, just recently shared on their OpenCourseWare youtube channel:
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.
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.