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Cake day: June 12th, 2023

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  • That’s not how AC works at all.

    AC works by evaporating a gas, evaporation (going from liquid to gas) takes a lot of energy. By dong this inside a ribbed evaporator, the energy gets extracted from the evaporator cooling it down. Then a fan ventilates the air in the room over the evaporator, which in turn extracts the energy from the air. On the other side the AC has a compressor which turns the gas into a liquid. This takes energy to do, so the compressor puts all that energy in, heating up in turn. A large condenser (looks like a radiator) is used to cool the coolant down. The compressor puts in energy in the form of pressure, but as the gas is hot it can’t turn into a liquid. By cooling it down in the condensor it can turn into a liquid. A fan is used over the condensor to dump the energy from the gas into the outside air.

    For gas in the past something like R134a was used, these days something like R290 (propane, but very pure/clean) is used which is better for the environment. In a very real sense ACs are energy pumps, they take the energy from inside and dump it outside. But they can also work the other way around, taking energy from outside and dumping it inside. This leads to pretty cool effects where you can heat your home with more than 100% efficiency. Because the energy you need to put in is only the overhead for pumping the energy, but the amount of energy being pumped can by much much larger. Over 100% efficiency in a closed system isn’t possible, but since an AC dumps the energy in the outside air it isn’t a closed system. ACs are also known as heatpumps for this reason.

    The way an AC can be used to dehumidify is because of the dew point in the air. This is a combination of the amount of moisture in the air, the pressure and the temperature. When the AC pushes the temperature from above the dew point to below, the air can’t contain all the moisture it contains. This will cause the water to condens on the evaporator in the AC. This can (and probably will unless you are in a very dry area) occur during normal cooling operation. This is why there are normally lines to take the water and get it out of the AC unit. When the water would remain, it’s a breading ground for all sorts of nasty stuff (look up legionnaires disease), so it’s important to get it out of there. A lot of times a small water pump is used to pump the water away.

    When cooling the AC tries to regulate the amount of energy pumped to keep a constant temperature in the room. Older/cheaper ACs just do this by start/stop, but better more modern ACs can regulate their power to prevent big swings in temperature and save energy. But when in dehumidify mode, the only purpose is to push the condensor below the dew point. Now the AC could do all sorts of fancy calculations to figure out the dew point and get it there. However that isn’t done at all, most ACs just push the temperature down as hard as they can. This is because the further you get down below the dew point, the more water condenses, so it gets the moisture out faster. And it’s also really complicated to calculate the exact dew point and get the measurements, because the AC itself influences the measurements a lot, so it would need sensors further away. Some big systems can do this and also measure the amount of moisture in the air and regulate to that. But small systems people have at home usually just go as hard as possible.

    This is the reason why it just never stops in dehumidify mode and the air gets colder and colder. Nerds can probably get something cooking with sensors and homeassistant, but regular home systems won’t go to a target when in dehumidify mode. There are hard limits to how cold it will allow the condensor to get, to protect the system and prevent frost, but that’s not really the same as a target temperature in cooling mode.

    Some better ACs also have a smart dehumidify mode, where it closes the inside unit, turns off the fan. Then cools down the condensor a huge amount. Then opens the inside unit and slowly blows air. This way it can get a lot of moisture out of the air fast and not cool down the air a lot at once. But in the end it’s the same effect. The energy still comes from the room, so the room will cool down, it will just not have huge swings in temperature.





  • My personal advice: Take notes.

    Just write everything down. I recommend an actual physical little paper notebook and a pencil. If you think: “Oh I must remember that” or “I’m almost out of …, I must buy more”, write it down.

    Now don’t go writing down stuff like fun facts or YouTube videos you want to watch. Make it all practical stuff, stuff you need to do or is important in your life. It’s your brothers birthday next week, write down the date and what you need to do to prepare. Your stomach hurt and you think you ate something that didn’t agree with you, keep a log of what you ate and how your stomach felt. That way you can identify allergies or things you can’t eat (anymore). Having trouble remembering names? Write down after you met someone: “Today I met Steve, Steve is in charge of accounting at Megacorp.” Measured the room you want to put new flooring in? Make a little sketch and put the measurements in.

    Writing stuff down physically forces your mind to pay attention and remember it later in a structured way. It also feels really good to physically tick off a task or cross it off. It can be a bit hard to keep up with and not go the other way and put so much into it, it doesn’t help anymore. But it can help a lot, especially if you are the kind of person that thinks 8 times a day to put out the garbage, only to wake up the next morning and you’ve forgotten to actually do the thing.




  • Well, I don’t think it’s worth repeating the debate again. You can go back and look at what was posted back when it came out.

    But he tells a very one sided story and keeps telling to keep an open mind. He presents this thing as if it’s totally unique and amazing, where there are very similar structures in nature out there. He also heavily focuses on the idea of it being a motor in the way that a human designed motor works, giving the same names to parts which are kind of similar on a surface level but really aren’t. He also repeats all of the bible thumper talking points around this subject, as if it’s a mystery nobody can explain and couldn’t have come to be without some kind of intelligent design at the helm. But the reality is, this is not representing the reality at all. This whole flagella thing was an exercise of goal post moving in the first place. The ID people kept pointing out weird things and missing links. Then when science explained exactly how that thing came to be, without ID involved, they just pointed to the next thing at one point ending up at flagella.

    There is a whole Wikipedia page talking about how flagella evolved and how it came to be. The intelligent design people have been shouting about this for 3 decades now and there is so much info out there to find about how this came to be. If Destin wanted to approach this from a scientific standpoint, he would focus on that information, instead of presenting it like some kind of mystery we are still figuring it out today. And not keep telling people to have an open mind and how he can’t figure it out. He could have even gone into why people might think it was ID and then explain the science why it is not. Something other online science communicators often do, give people the points they have been hearing from the “wrong” side and then go into those points and explain them.

    Basically the whole subject itself is very hard to present without going into the whole ID versus evolution standpoint and the way he represented it was straight out of the ID playbook. And keep in mind all of this was thoroughly debunked back 20 years ago. Him bringing this up now is inexcusable.

    I’m not even sure there is research still being done on this, the research was done decades before, there is no mystery.






  • You are right in how wasteful it is, especially since it turned out a lot of those satellites don’t even make it to 4 years.

    However there is zero risk of space trash with Starlink. They orbit so low, it’s basically within the atmosphere still. They need to constantly boost themselves, otherwise they fall down and burn up. So these satellites are coming down within years all on their own, even without any controlled disposal.

    It’s insanely wasteful, but it keeps SpaceX in business launching every week, which is kind of the point. But at least there isn’t a Kessler syndrome waiting to happen.





  • Who fucking cares at this point? Trump has done so much worse things by now. He can’t legally be president for a third term, so it’s not like it’s gonna impact his re-election. Most of the world already hates the man and think he is vile and disgusting. What is one pee tape going to change.

    The pee tape could release today and be barely in the current news cycle. One camp will say “This just confirmed what we already knew”, the other camp will say “Fake news”. And tomorrow it will be forgotten.

    No, it has to be something way worse than a simple pee video.