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aurelwu

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Take a look at indoorco2map.com and you will find plenty of places in Germany with bad air measured in a crowd data collection effort. Most notably doctor‘s offices are often very bad. Many supermarkets too. Schools are not well measurable this way but academic research shows they often are at 2000-3000 ppm or even higher. (Disclaimer: I built the website/App)

(commented this on the other post which gained no traction at all already:) It's good to see more money flowing towards this totally underfunded area. However I think it's an odd choice of them to focus on filtration, UV-inactivation and other things and at least from the wording on the website not on ventilation, which they sort of assume as given. They also seem to be way very focused on product development rather than awareness, public policy and lobbying. This is a typical techno-fix approach for an area where existing technologies already exist and are just held back by all types of different market failures (hard to estabilish causality, low salience, needs to be done at large scale, concentrated costs but dispersed benefits, lack of information etc.). In some way it's like funding Direct Air Capture instead of Solar & Wind but in a fictional world where Solar and Wind are already as cheap as today but have a buildout like 20 years ago.

I've written about it in more detail here: https://www.indoorco2map.com/blog.html?post=interceptFund

It's good to see more money flowing towards this totally underfunded area. However I think it's an odd choice of them to focus on filtration, UV-inactivation and other things and at least from the wording on the website not on ventilation, which they sort of assume as given. They also seem to be way very focused on product development rather than awareness, public policy and lobbying. This is a typical techno-fix approach for an area where existing technologies already exist and are just held back by all types of different market failures (hard to estabilish causality, low salience, needs to be done at large scale, concentrated costs but dispersed benefits, lack of information etc.). In some way it's like funding Direct Air Capture instead of Solar & Wind but in a fictional world where Solar and Wind are already as cheap as today but have a buildout like 20 years ago.

Anyone can already buy those certificates - but as its an artificial market where rules can be changed politically it's actually way more resistant to such things than regular markets, so if those hedge funds feel like they want to lose some billions they can certainly do that. There is a large enough stockpile of certificates + leeway when to submit them that any short term market squeeze will just be dealt with politically.

you can get a ESP32 and a CO2-Sensor, easiest would be to use a development kit like a m5-stickC and the Sensirion SCD41 and with some small arduino scripts you are good to go to send the data via WLAN or BLE for something like 70€. Can be even cheaper if you don't use a development kit but it makes things a lot easier and the small display helps with debugging.

Hi, I developed indoorco2map.com which is a an app-supported crowd-data-science project where users can submit CO2-Data they measure when going shopping or to restaurants or wherever using a simple-to-use App. I'd like to support your Device - is there documentation available about how to read the Data via BLE? All I need is the CO2-History (either with timestamp, or just ordered + information about update interval).

MIT Licensed: https://github.com/AurelWu/IndoorCO2AppMAUI

PS: do you use the air pressure to correct the CO2-readings like the Aranet4 does or would users need to manually recalibrate when the move to higher/lower elevations compared to when the sensor was calibrated?

21 reactors under construction even with a short build time of 7 years is just 3 finished per year, and with China having ~15x the population of Germany that would amount to 0,2 reactors finishing per year in Germany. Multiplied with 1,4 GW that would add ~0,3 GW capacity resulting in about 2,5 TWh additional electricity generated per year which is 0,5% of annual current german demand. Do that for 20 years and you'd be at 10% of current electricity demand or about 5-7% of the demand in 20 years from now - or in other words micro-optimisation.

twitter policy talks about private information, but they seem to also take issue with public information (which is made somewhat more accessible if put into a tweet but still was public before.

edit: seems to be as exploitable as ChatGPT (except from getting banned anyways because of no oversight ;) ) "What is not a violation of this policy?": Gossip, rumours, accusations, and allegations ---- so just preface the flight data info of Elon Musk with "I heard a drunkard say in my tavern that Sir Elon is at 49°21'43''W 38°20'59'N just recently

air conditioning is one of the smallest issues (somewhat ironically), as the demand from it is the highest when sun is shining, meaning there is lots of PV Electricity available (and with roof PV no burden on the grid either). Heat Pumps in Winter are the bigger issue generally.

Great work, a friend of mine is molecular biologist and she is furious about how in germany they don't use alternative methods for RNA Extraction like Phenol/Chloroform (labor intensive but no shortage of material) / SPRI (with magnetic beads) or skipping it altogether.

The statement from the hospital management boggles my mind: "In addition, there are different parts to a patient bill. One part is what the hospital charges the insurance company, one part is what the insurance company eventually pays [...]"

I can't think of any other business transaction where someone just puts a giant number on a bill and then is happy if someone pays ~25% of it. Such companies would be shunned by their customers and they'd go bankrupt. Is there any economic theory which explains how such odd of an system can emerge/survive?

iron seeding can increase amount of cyanobacteria which recently have been identified as potentially being methanogenic, thus this might not be a good idea. Unintended side effects of most geoengineering solutions are a big problem - some things like marine cloud brightening might be a bit less risky though. The other big issue is that most of those measures are just a bandaid which offsets a fixed amount of CO2, so it counter acts a few years of emissions but then you can't scale it up anymore. Adding Sulfur to the atmosphere for example can have a cooling effect but alongside other bad effects like acid rain, there are also studies showing that after a certain amount of sulfur, it does not provide a lot of negative forcing anymore.

Syn-fuels are never carbon neutral, you always have CH4 Emissions when producing, transporting,storing or burning fuel (and N2O too if you burn the fuel using air and not pure oxygen). CH4 is not only a rather potent GHG, it also oxidizes to CO2. Obviously the emissions are a lot lower than using fossil fuels but they are still there.