> This is an industrial designed exercise bike from Lithuania that can store 2KWh of electricity generated by your own exercise.

I found these kind of cool as an idea, as they can be added rather easily to existing cities and provide some greenery without taking up space, while providing shade: https://www.singulargreen.com/en/green-shades-valladolid/

It's so rare to actually see a new battery tech exit the lab and enter production. Always seems like there's 10,000 new up and coming breakthroughs in battery technology, but none ever leave the workbench. While Na-ion batteries don't have the energy density of Li-ion, they make up for it with many other factors such as more abundant source materials, increased safety, higher charge/discharge currents, and increased number of charge cycles. **Slashdot summary**: >Not only is sodium somewhere between 500 to 1,000 times more abundant than lithium on the planet we call Earth, sourcing it doesn't necessitate the same type of earth-scarring extraction. Even moving beyond the sodium vs lithium surname comparison, Natron says its sodium-ion batteries are made entirely from abundantly available commodity materials that also include aluminum, iron and manganese. Furthermore, the materials for Natron's sodium-ion chemistry can be procured through a reliable US-based domestic supply chain free from geopolitical disruption. The same cannot be said for common lithium-ion materials like cobalt and nickel. >Sodium-ion tech has received heightened interest in recent years as a more reliable, potentially cheaper energy storage medium. While its energy density lags behind lithium-ion, advantages such as faster cycling, longer lifespan and safer, non-flammable end use have made sodium-ion an attractive alternative, especially for stationary uses like data center and EV charger backup storage. [...] Natron says its batteries charge and discharge at rates 10 times faster than lithium-ion, a level of immediate charge/discharge capability that makes the batteries a prime contender for the ups and downs of backup power storage. Also helping in that use case is an estimated lifespan of 50,000 cycles.

A good overview and link collection around small scale hydro power technologies

I was watchin the last episode of ''earthsounds'' (docuseries that you can find on torrent) and they said to have used one of this with a microphone mounted under it to record better sounds from whales (because they travel a looooooot and not always on the same routes). Autonomous robot solarpowered to catch better ocean data, pretty solarpunk to me :3 p.s. the series is nice even tho first 4 episodes have much more cool sounds; it's also interesting to see how hard it is to capture the sounds at the end of every episode p.p.s. ye, it's not open source, by a company owned by boeing and probably also used for militar purposes so it's not perfectly as we would like it to be

💩 tech! On a serious note, this was in my random recommends and I clicked it and now I know about something I had no idea even existed. If this technology can come to fruition, it'll be great for the world.

This is quite exciting in that it removes plastic waste. I see no reason why different companies can't make different shape ones to maintain their lock-in. I expect a knock-off market to pop-up, but that exists with plastic pods too. It's a step in the right direction at least.

A wild Anker enters the home battery market.

This might be a bit of a reach but I’m wondering if anyone here knows enough about concrete production to help me plan the layout of my next photobash. I’d like to do a scene of a solar-thermal concrete factory – there are several supposedly in the works, like [Synhelion’s new partnership with Cemex, funded by the](https://www.renewableenergyworld.com/solar/doe-funds-concentrated-solar-thermal-project-for-cement-production/#gref) [US DoE](https://www.energy.gov/eere/iedo/cement-and-concrete-manufacturing), or the french company [Solpart](https://www.wired.com/story/a-solar-breakthrough-wont-solve-cements-carbon-problem/) (whose prototype involved a rotary kiln), or Heliogen. Unfortunately I’ve had a lot of trouble finding decent photos of their setups, and even though Synhelion is apparently working on a pilot industrial-scale solar concrete plant, I haven’t found any plans to work from. I’ve been doing some reading about existing concrete factories, and plan to keep as much as possible the same, while mostly modifying the kiln to include at least one structure similar to a solar falling particle receiver, and adding some onsite algae farms or greenhouses for capturing CO2 released by the burning of the lime, and a trainyard (either electric trains or fireless steam locomotives, given that it’s a solar plant) for moving material into and out of the plant. I’ll say upfront I know *very* little about concrete production, and I’m struggling to come up with a kiln design that’ll hit the required temps for long enough, without [burning the lime and messing it up.](https://www.tappi.org/content/events/08kros/manuscripts/2-2.pdf). Originally I’d pictured basically a rotating kiln feeding into a falling particle receiver, linked up so heat from the sunlight hitting the falling concrete could still travel up the tube and eventually up into the cyclones where the mix is dried. But it seems like the concrete needs a longer, slower firing time than whatever heat it gets wafting up from the aperture, and then a blast of light and heat as it goes past. The [diagrams I could find](https://www.researchgate.net/figure/Solar-rotary-kiln-as-a-calciner-used-at-the-DLR_fig3_334367852) seems to just be a rotary kiln with sunlight being blasted into the open lower end, but I’m not sure if that’s just the design they went with because it was a proof of concept prototype. I also know that temperature changes are bad for lining of rotary kilns, which are normally run pretty constantly IRL, so it seems like they’d need some changes anyways to cope with the day night cycle? In case you’re reading this and wondering why make concrete this way, the concrete industry is a huge portion of human CO2 production (around 8% total), due both to the release of CO2 from the chemical process of baking the limestone, and from the tremendous amounts of heat necessary for doing that. A more solarpunk society would hopefully use much less concrete overall, especially with changes in building design and priorities that allow for weaker materials like hempcrete and mycocrete, but for some things we’re still going to need modern concrete. Solar furnaces can hit temps well above what a rotary kiln uses, and heliostat systems aren’t far behind, and it’s a pretty direct use of heat from the sun, which would minimize conversion losses. It’s not a great fit for every current concrete plant, but it seems like it could help.

Researchers in China have reportedly developed a new technology similar to hydropanels for harvesting water out of thin air that is powered by energy from the sun. The device could be especially useful in dry, arid areas where water — but not sunlight — is hard to come by. The findings from the research team from Shanghai Jiao Tong University in China were published in the scientific journal Applied Physics Reviews. "This atmospheric water harvesting technology can be used to increase the daily water supply needs, such as household drinking water, industrial water, and water for personal hygiene," said Ruzhu Wang, one of the study's authors. According to the study, the device is more efficient than other existing atmospheric water generators because it uses a "novel rotating operational strategy, in which one module works in the desorption, while the others work in the adsorption simultaneously … to keep the device harvesting water continuously." The technology could also be used for purposes ranging from dehumidification to agriculture irrigation to thermal management for electronic devices.

This seems like a great technology to build resiliency and redundancy in a community, especially for places where cell service is spotty, or in the odd event where normal lines of communication are blocked. The LoRa boards can be [easily powered with a small solar panel](https://www.youtube.com/watch?v=DumgHz56IjI) for continuous use, and if put in a high enough place with a good antenna, they can have a [surprisingly long range](https://hackaday.com/2023/09/15/new-lora-distance-record-830-miles/)! In addition to being genuinely useful, they also seem like they'd be a lot of fun to experiment and play around with, printing cool 3D cases for them, or designing a better [antenna or repeater setup.](https://hackaday.com/2023/09/15/new-lora-distance-record-830-miles/) If and of you already have experience with LoRa, I'd be interested to hear your thoughts! :D

cross-posted from: https://slrpnk.net/post/8609299 > The Ultimate CyberDeck for Encrypted Messaging over a Meshnet > > The lilygo t deck is an all in one device that includes a LoRa antenna with a screen and keyboard for messaging people over long distances without any internet using the open source end to end encrypted software Meshtastic. > > The video is way longer than it needs to be but you can see the device in action. There’s a growing community of people making meshnets using Meshtastic in different cities. .

what bugs me the most is thinking that if lemmy became as relevant as reddit, servers to spam all over the threadiverse would be created nonstop ***does anyone have some resources into solutions for spam in stuff like email?*** i'd like to check if having some giants gatekeepers like microsoft and google is inevitable

cross-posted from: https://lemmy.ml/post/14059725 > Plastic-Free Vegan Leather that Dyes Itself Grown from Bacteria

Did someone say airship?

An interesting tool from the article is ecograder.com which grades a website's carbon emissions and provides recommendations to improve. There is also the Green Web Foundation's [directory of hosting providers powered by renewable energy](https://app.greenweb.org/directory/). [This is the report](https://ecograder.com/report/sLw3nmVBPaiUWi8DRJc1oCd1) for slrpnk.

For example water driven sawmills to cut wood