perestroika

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[–] [email protected] 3 points 1 day ago

P.S. I have once used DC to power a pump "directly". I use quotation marks because the pump (a water pump) was a brushless DC motor with an integrated controller. I used it on a field for removing water after a spring flood. Its controller accepted 24..48 V input, and it was powered from a 40 V solar panel brought on a wheelbarrow. :)

[–] [email protected] 5 points 1 day ago* (last edited 1 day ago) (1 children)

instead of powering the heat pump from the wall, the heat pump can be connected directly to a PV

I have no experience with this exact combination. I know that "batteryless" inverters exist, but most of them are on-grid inverters. In that scenario, all that matters is monitoring your production: if you don't want grid energy, you only run your system when your PV produces enough.

Another type of batteryless inverters are "pump inverters". Farmers seem to like them for pumping water from wells into water towers. A pump inverter can be configured to run at 50 Hz (or 60 Hz for North Americans) and 230..240 V (or 110 V for North Americans) alright, but it is not designed to power electronic devices, but dumb agricultural motors. There is considerable risk involved with powering a heat pump from a pump inverter, unless you find an exceptionally simple and dumb heat pump with very limited or resilient steering electronics.

Efficiency losses are small anyway, but mostly happen during battery storage or when voltage needs to rise or drop considerably (e.g. a transition of 700 -> 24 V or 24 -> 240 V would cause a small efficiency loss).

I’ve heard that a PV can directly power a compressor

This seems unlikely as the compressor would have to be a brushed DC motor. That kind of motors don't last long, they wear out their brushes. Long-lasting motors are brushless, and those generally cannot be run on DC power. For example, a "brushless DC" motor is essentially a three-phased AC motor, just its controller (full of smartness and MOSFET transistors) accepts DC input.

If you have a good technical overview of your heat pump system, maybe you can locate a point where regulated DC can be fed into the system, but that would be hacking. Alternatively, maybe a niche market already exists for DC-powered heat pumps, e.g. for caravans, trucks or ships? But on niche markets, prices typically aren't good for you. :(

[–] [email protected] 1 points 1 week ago

Mulje: arutelu oli huvitav, kuid aega oli selleks liiga vähe. Kohal oli mitukümmend inimest, kellest osad kirjutavad ministeeriumile enne kooskõlastusringi tähtaja lõppu.

Kohal oli siseminister Läänemetsa nõunik, kes veidi ümarat juttu ajas, kuid ilmselt ka kõrvad lahti hoidis.

Eks vaatame, mida sealt tuleb. Kui tuleb mingi halva maiguga eelnõu, siis peab lipud ja loosungid kolikambrist välja otsima.

[–] [email protected] 4 points 1 week ago (1 children)

Relays: my use for truck relays is switching on heaters in my thermal storage water tank. Not big ones, though - I use relays rated for 24V and 40A of current. Since they are old, I have applied a safety margin and only let 25 A flow through them, so each of them handles 24 x 25 = 600 W.

As for using DC appliances: benefits do exist. If a household has a low voltage DC battery bank (some do, some don't) then dropping the battery voltage a few times to power car parts comes with a smaller efficiency loss. In my household, DC appliances are used for lighting, communications, computing, cooling food, pumping water and soldering electronics. The rest goes via AC. I think a car air conditioner could cool some small storage room decently. With big living rooms, it would have difficulty since it's a small device.

[–] [email protected] 2 points 1 week ago* (last edited 1 week ago)

it would (as far as i understand with high school chemistry) be strictly more efficient to electrolyse rust directly

I'm not a chemist either, but I do know a bit of chemistry.

Typically, you need a solution of NaOH (sodium hydroxide) to directly reduce iron oxide in an electrolysis cell. If your iron oxide contains impurities, those may react with NaOH and ruin the fun. Also, if you have exposure to CO2, your NaOH will gradually degrade, producing NaHCO3 and losing potency.

My impression: wet electrolysis is great for making high purity iron, but it would be hard to make it work for energy storage.

[–] [email protected] 8 points 1 week ago* (last edited 1 week ago) (5 children)

Relays can be used for anything, and a car contains a fair number.

You can make a pulse jet engine from a muffler parts, but a solarpunk society would probably not do that. :)

Copper brake pipe and cooling radiators can be used as heat exchangers for other stuff.

Air conditioner parts can be reverse-used for Stirling engines or to pump heat in other contexts.

[–] [email protected] 2 points 1 week ago* (last edited 1 week ago)

Wow, really interesting tools. :)

But sadly not for me - I left biology behind at some point and have fallen off the sleigh so badly that I'd probably need a year of study before I could use this tool for something less than practical (e.g. make a bacterium glow in the dark).

 

Kolleegid anarhistid, meile võib olla tööd. Aastal 2008 tõstsime meie sildi "Ei politseiriigile", kui siseminister Jüri Pihl pärast Pronksiööd politsei õigustega üle põhiseaduse ratsutada tahtis. Põhiõiguste piiramise teema ei ole sellest ajast kordagi täielikult silmapiirilt kadunud (netivabadus, metainfo talletamine, sõrmejäljed, jne). Praegu on sama sildi tõstnud kas jälle meie, või seekord keskid teised. Sildil on esialgu ka küsimärke.

Tallinnas, Põhjala tehase Ankrusaalis toimub 4. septembril kell algusega kell 19:00 uue korrakaitseseaduse kriitiline arutelu. Arutelu juhtatavad sisse õigusteadlane Paloma Krõõt Tupay ja vandeadvokaat Kalev Aavik.

Olete oodatud, kuid ma ei julge lubada koosoleku kohta midagi, kuna ei tunne kedagi selle korraldajatest. Info toimumisest leidsin Feministeeriumi kaudu.

Ürituse kutse leiab siit (ettevaatust, Facebooki link).


Colleagues, anarchists, we may have some work awaiting. Back in 2008, we raised the banner "No to a police state" when interior minister Jüri Pihl wanted to ride roughly over the constitution after the "bronze statue riot". The topic has never really died after that (internet freedoms, data retention, fingerprinting requirements, etc). Currently, someone has raised the same banner, but we don't yet know if it's us or someone else. :)

On September 4 at 19:00 in Tallinn, at the "Anchor hall" (Ankrusaal) of the Põhjala factory, there will be a critical discussion of the new law enforcement bill. An introduction will be made by Paloma Krõõt Tupay (who researches law) and Kalev Aavik (who practises as a lawyer).

You're welcome to join, but I cannot promise anything about the event, because I don't have contact with the organizers. I found the information via Feministeerium.

An invitation to the event can be found here (beware, Facebook link).

[–] [email protected] 5 points 2 weeks ago* (last edited 2 weeks ago)

This one didn't have rocket boosters, but was also nice: :)

( it traveled 180 km on one charge, back in 2009 :D )

[–] [email protected] 3 points 2 weeks ago* (last edited 2 weeks ago) (1 children)

Wow. :)

I was expecting something with rotor sails, but I click, and it's a fancy new derivative of schooners. :)

As a result, I guess that rotating masts aren't optimal after all - too much moving mass, impossible to take down during a hurricane, etc.

I also guess that this sailboat has a fairly good motor, for use during total lack of wind (rare) or storms that would damage sails or masts.

 

This is not just a "happy birthday" post for Linux, but also a reminder that despite it becoming big and professional, the freedom to tinker with Linux remains accessible.

I had to use this freedom recently when I discovered that V4L video pipelines could buffer up to 32 frames both on the encoder and decoder (unacceptable, we demand minimum latency!) so it was again time to recompile the kernel. :)

My previous time to recompile parts of Linux had been a week ago. Some hacker had discovered a way of tricking their WiFi card beyond the legally permitted power - with what I understand as thermal compensation settings. Wanting to taste the sweet extra milliwatts, I noticed that nobody was packaging that driver as a binary, so the only way to get it was to patch and recompile its kernel module.

Finally of course, thanks to Linux we have countless open-source drivers and if you want to venture onto the path that Linus Torvalds took - of building an operating system - congratulations, you have less obstacles in your way. :) Some people have taken this path with the Circle project and you can compile your homebrew and bare-metal kernel for a Raspberry Pi with reasonable effort, and it can even draw on the screen, write to serial ports and flip GPIO lines without reverse-engineering anyone's trade secrets. :)

[–] [email protected] 10 points 3 weeks ago* (last edited 3 weeks ago)

Regarding infiltration of the police - a similar theme played out in Greece during the 2008 economic crisis, when Golden Dawn vied for power - they tried hard to infiltrate the police, and succeeded to a considerable degree.

At some point, they made a mistake, though - GD thugs killed a popular leftist rapper named Pavlos Fyssas. He was able to point out who stabbed him. His death caused widespread rioting. Rioting incapacitated GD temporarily by blocking and damaging their party offices while the security service raided high-ranking members for evidence (apparently they didn't manage to infiltrate counterintelligence and in the confusion probably couldn't dispose of evidence even if they knew of incoming raids) ...and evidence was plentiful. They were banned and leaders got meaningful sentences in courts.

Only in a country where entering the police force requires lengthy studies to obtain a diploma (and background checks), is there some chance of random bozos not worming their way in. Most states of the US aren't such a place, sadly.

[–] [email protected] 4 points 3 weeks ago* (last edited 3 weeks ago) (1 children)

I wonder what the structure could have been in the past? A navigation light pillar? A ventilation shaft riser for some underground thing?

[–] [email protected] 6 points 4 weeks ago* (last edited 4 weeks ago) (2 children)

Yep, indeed, I'm already discovering differences too. :) A good document for techies to read seems to be here.

https://reticulum.network/manual/understanding.html

I also think I see a problem on the horizon: announce traffic volume. According to this description, it seems that Reticulum tries to forward all announces to every transport node (router). In a small network, that's OK. In a big network, this can become a challenge (disclaimer: I've participated in building I2P, but ages ago, but I still remember some stuff well enough to predict where a problem might pop up). Maintenance of the routing table / network database / is among the biggest challenges when things get intercontinental.

 

Järjehoidja .ee anarhistidele: lemm.ee serveris on kah anarhismi teemaline kanal. See loodi äsja ning suurt midagi hetkel veel ei toimu. :)

A bookmark for anarhists in .ee: please note, on the server lemm.ee, there is also a channel about anarchism. It appeared recently and there is not much to see currently. :)

 

In the article, researchers modeled the passage of the solar system through the galactic interstellar medium, components of which move at differing velocities and orbits.

They found that approximately 2-3 megayears ago, the solar system most likely entered a cloud of mainly cold hydrogen, and the density of the cloud was such that it should have considerably compressed the heliosphere (Sun's bubble of radiation and fields). Earth would have been outside the heliosphere either permanently or periodically. Currently the heliosphere ends far beyond the most distant planet, at approximately 130 Earth-Sun distances (astronomical units).

This would have greatly subdued the influence of solar wind on Earth, at the same time exposing the planet to interstellar cosmic rays. It is further speculated that studies which analyze Earth climate during the aforementioned period may benefit from accounting for this possibility.

Researchers sought confirmation for their model from geological records and found some, in the isotope content of iron and plutonium in sediments: iron 60 and plutonium 244 aren't produced by processes on Earth, so an influx would mean that solar wind no longer sufficed to beat back interstellar gas and dust (the latter containing radioisotopes from supernova explosions).

"By studying geological radioisotopes on Earth, we can learn about the past of the heliosphere. 60Fe is predominantly produced in supernova explosions and becomes trapped in interstellar dust grains. 60Fe has a half-life of 2.6 Myr, and 244Pu has a half-life of 80.7 Myr. 60Fe is not naturally produced on Earth, and so its presence is an indicator of supernova explosions within the last few (~10) million years. 244Pu is produced through the r-process that is thought to occur in neutron star mergers22. Evidence for the deposition of extraterrestrial 60Fe onto Earth has been found in deep-sea sediments and ferromanganese crusts between 1.7 and 3.2 Ma (refs. 23,24,25,26,27), in Antarctic snow [28] and in lunar samples [29]. The abundances were derived from new high-precision accelerator mass spectrometry measurements. The 244Pu/60Fe influx ratios are similar at ~2 Ma, and there is evidence of a second peak at ~7 Ma (refs. 23,24)."

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submitted 3 months ago* (last edited 3 months ago) by [email protected] to c/[email protected]
 

Since Estonian readers know already, this summary is only for English speakers: after many years of haunting the political landscape with gradually growing vote counts, the Estonian Conservative People's Party (authoritarian right), has finally collapsed into a crisis.

It's not a crisis of values (they are all still conservative and many are authoritarian too), but a crisis of internal democracy due to the dictatorial habits of the "ruling family" - father and son Mart and Martin Helme.

Three prominent members, one of whom intending to challenge the party leader in internal elections, were kicked out during a board meeting, after which several more prominent members (among them several MPs and one MEP) either left the party of announced intention of leaving.

Everyone involved had adequate warning about the lack of internal democracy, it is just that they tolerated it longer than anticipated. The big bang comes after years of gradual kick-outs.

""If you wait by the river long enough, the bodies of your enemies will float by." - Sun Tzu

 

For English speakers: boring but scandalous tax news from Estonia. If the proposed changes are passed into law, it will no longer be possible to pay a progressive income tax in Estonia even voluntarily (by having an automatically taxed "entrepreneur's private account"). It's surreal. The state budget is tearing apart after the COVID expenses, military expenses due to our dear eastern neighbour [both unavoidable, I would say] and meanwhile politicians find ways to ease the tax burden on the well-earning (I am one of them and have paid the higher tax tier on some years). And of course - the really wealthy folks who own actual companies - they never had to pay it. Me, I'm going to wait until the dust settles and publish something about this farce, as I think the progressive tax system should be expanded, not ended.

Lühikokkuvõte: Eestis ei saa astmelist tulumaksu enam isegi vabatahtlikult maksta. Päris rikkad pole seda kunagi maksma pidanud, aga nüüd ei saa seda maksta ka üksi tegutsevad väikeettevõtjad. Riigieelarve käriseb pärast pandeemiat ja sõda Ukrainas sunnib peale vältimatud kõrged kaitsekulutused, aga meil plaanitakse jõukamate klasside maksukoormust langetada. Sürreaalne. :o Ootan, kuni tolm langeb ja pilt selgineb, siis tuleb selle kohta artikkel.

 

For English speakers: I've previously written about the Helsinki thermal store. Now I'm happy to mention the planned Vantaa thermal store, which is going to be built for 200 million euros and will store nearly enough heat to keep Vantaa warm through the winter (specifically 90 GWh). It's going to be charged with waste heat and direct electrical heating during periods of renewable energy overproduction.

Olen varem kirjutanud Helsingi soojushoidlast, nüüd saan mainida Vantaa oma - see rajatakse ca. 200 miljoni euro eest ja suudab valmides salvestada põhimõtteliselt kogu Vantaa talvise vajaduse jagu küttesoojust. Soojushoidlat kavatsetakse täita jääksoojusega solgiveest, andmekeskustest ja 2 x 60 MW otsese elektriküttega taastuvenergia ületoodangu perioodidel. Väga huvitav projekt, millele õnnestumist sooviks.

 

For English speakers: an article from the Estonian public broadcaster about the Slovakian public broadcaster (and government). Unfortunately, there's some sad news - the new government of Slovakia is intending to tear down and rebuild from scratch their public broadcasting company. And everyone knows what that means: convenient people will be installed in the offices that count, so that news could be more favourable for the government in future. Stage 1 of authoritarian takeover. There is opposition to it, of course, and hopefully it won't get anywhere.


Slovakkia kandist on nukrad uudised: uus valitsus juba sirutab kätt avalik-õigusliku meedia järele, eesmärgiga et suure ümber struktureerimise kattevarjus "omad joped" ametisse panna ja tulevikus omale meelepärasemaid uudiseid toota. Riigi autoritaarse ülevõtmise retseptis on selline liigutus tähtsal kohal. Loodetavasti ebaõnnestub.

 

For English speakers: adopting a progressive income tax would be currently supported by 60% of Estonia's voters and opposed by 30% (support has previously been as high as 75%). The measure would be supported by 5 parties out of 6 and narrowly opposed by 1 party (which is split in the question). This has been the situation for 20 years. And the result? We have no progressive income tax, because politicians (who are nearly without exception high-income persons) aren't that keen on listening to the population in certain questions, and the population - easily distracted and clumsy at demanding stuff. :o


Nagu näha, toetaks meedet (jätkuvalt, juba ca. 20 aastat) nii elanikkonna enamus kui parteide enamus. Kõik peale praeguse peaministri erakonna toetaks astmelist tulumaksu, ja peaministri erakonnast kah pooled. Paraku ei ole seda juhtunud. Kurvastusega tuleb tõdeda, et poliitikuid (kes on pea eranditult kõrge sissetulekuga isikud) teatud küsimustes valijate soovid eriti ei huvita - valijad aga on hajameelsed ja oskamatud asjade nõudmisel. :o

 

Eesti Ekspress on pühendanud artikli Progressiivse Liikumise tegemistele. Kahjuks on nad selle toppinud maksumüüri taha. Kui ma maksumüürist tee ümber leian, kommenteerin all.

The paper Eesti Eksrpress has dedicated an article to the doings of the Progressive Movement. Unfortunately they have paywalled it. If I find a way past the paywall, I will comment below.

 

Summary for the English-speakers: last year Estonia, a country traditionally running on oil shale, has finally produced most of its electrical power from renewable sources. Renewables produced 2.6 TWh while fossils only 2.3 TWh - but the report is needlessly optimistic as 1.2 TWh out of the renewables still involved burning stuff (waste, wood chip and other biomass).


Verstapostist on mööda saadud, aga tegelikkus ilusate arvude taga on, et pool meie "taastuvenergiast" emiteerib süsihappegaasi. Siiski on ka see parem kui mitte midagi. :)

 

Background: yesterday, there was heated discussion in the thread "military-industrial complex is a supervillain of causing the climate crisis" (link).

Among others, the thread creator posted a comment to the Guardian article "The climate costs of war and militaries can no longer be ignored", commenting it thusly:

If you want more context or won’t take my word on how militarism will kill is all, you can read this article.

I replied, a copy of my reply is below for your judgement. My reply got moderated by someone with the reason "Comment does not address intent of original post and promotes weapons industry / war in Ukraine."

I think my comment both addressed the topic, did not promote the weapons industry but helping Ukraine defend itself (ironically, tools for military self-defense come from the weapons industry) and did not promote the war (in fact, I noted that war is expensive, resource-intensive and stupid), but did explain the dynamics of war and revolutions.

I consider this moderator misconduct, likely motivated by their political views - and have asked a server administrator to talk with the moderator involved, to ascertain if they can refrain from using moderator powers as a political club to hit people, or to secure their demotion from a moderating role.

The removed post, for your judgement:


The article is fine, and I second the recommendation to read it, but from the article to the slogan you present, things do not follow a logical path.

Yes, war is both an incredibly expensive activity (diverting money that could be used) and a resource-intensive activity (the money goes into actual materials that almost surely destroy something or get destroyed) and an incredibly stupid activity (and it can snowball)...

...but the problem is that successful unilateral disarmament during a war tends to result in a situation called "defeat". If the defeat is not an attack being defeated, but defense being defeated, that is called a "conquest". Now, letting a conquest succeed has a historical tendency of the conqueror having more experience at conquest, and more resources to conquer with... which has, several times in history, lead to another conquest or a whole series of conquests. A regional war in Ukraine resulting in Ukraine being taken over by Russia has a high probability of producing:

  1. a bigger regional war later, in which Russia, using its own resources and those of Ukraine, proceeds to another country, gets into a direct conflict with NATO and then indeed there is a risk of a global war
  1. an encouraging effect after which China, noting that international cooperation against the agressor was ultimately insufficient, and deeming itself better prepared than Russia, decides that it can take Taiwan with military force

However, a war ending with inability to show victory tends to produce a revolution in the invading country. For example, World War I produced a revolution in Russia and subsequently a revolution in Germany, with several smaller revolutions in between, empires collapsing and a brief bloom of democracy in Europe, before the Great Depression and the rise of fascism ate all the fruits. The Falklands War produced a revolution in Argentina. The Russo-Japanese war produced the 1905 near-revolution in Russia.

It is better for Ukraine to not get conquered. It is better for Russia to be unable to conquer Ukraine. That result is also better for everyone around them. It's even better globally because it sets a precedent of large-scale cooperation defeating an agressive superpower, discouraging agressive superpowers from undertaking similar wars until memory starts fading again.

Unfortunately, until we see indications that Russian society is getting ready to stop the war (this could involve starting negotiations on terms palatable to Ukraine, a change of leadership, a withdrawal, a revolution, etc)... the path to achieving that outcome remains wearing out the agressor: producing enough weapons and delivering them to Ukraine.

Ultimately, both sides in a war wear each other down. The soldiers most eager to fight are killed soonest. The people most unwilling to get mobilized or recruited, and soldiers most unwilling to fight - they remain alive. If they are pressed forever, some day they will make the calculation: there are less troops blocking the way home than in the trenches of the opposing side. After that realization, they eventually tend to mutiny. Invading troops tend to do that a bit easier than defending troops, because they sense less purpose in their activity. In the long run, if nothing else happens, that will happen. There is just (probably, regrettably) no particularly quick shortcut to getting there.

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