• 18 Posts
  • 1.37K Comments
Joined 1 year ago
cake
Cake day: June 12th, 2023

help-circle
  • Yeah I don’t really see how that’s possible. Even if you get a material that’s able to harvest at 20% efficiency, getting the energy out is a big issue. It’s a lot of power and transporting it through a layer a few micron thick is very rough and leads to huge losses.

    I also don’t know what “math” they actually did. I think it was some back of the napkin extrapolations and not actual data. For example they state: “one scientist suggested covering an entire car with the new solar paint, ramping up the surface area to more than 11m2” That leads me to believe they didn’t actually do anything but were just extrapolating and speculating for the press.

    They also state: “scientists hardwired the body panels to the Benz’s high-voltage battery”. This makes zero sense. In order for energy to flow from a solar panel into for example a battery, the voltage of the panel needs to be higher than the voltage of the battery. Otherwise the current will flow in the wrong direction. But Mercedes EQS batteries run at 400 volt, you can’t connect “directly” to the battery unless you want the panel to explode and the car to catch fire. And even if you connect it directly into some charger system that can convert the voltage from the panel into something the battery can use to charge, you wouldn’t want to do it like that. Including a voltage optimizer in the system is key for getting efficiency out of a solar panel.

    I think some journalist misunderstood some Merc tech demo and made up this BS story.


  • Yeah this is total BS.

    The sun delivers about 1.3kW of energy per square meter and an average car takes up about 8 square meters of space. So that’s about 11kW to work with, but even very efficient solar panels only harvest about 20% of that. So that leaves us with about 2.2kW to work with. Now in order to convert that energy into something usable and charge the battery, more losses are added, depending on the situation this would be around 20%, leaving 1.76kW. This means charging a 50kWh battery would take around 28 hours. Obviously we can only expect around 6 hours of really good sun on an average day, with the rest of the day having much less energy available. So charging the car would take several days in perfect conditions. If it’s cloudy, if it’s raining, if you’ve got shade over the car, if you drive the car etc. it will take more time to charge it.

    In reality however, this is with modern commercial grade equipment, oriented perfectly to the sun at the proper angle. Putting that in a car isn’t possible. Stuff is going to get hot, which leads to reduced efficiency, active cooling costs energy so that’s probably not a good solution. The car isn’t going to have all of it’s surface facing the sun, by definition a part of it is going to be in it’s own shade. If the sun is perfectly overhead for max efficiency on the roof, the sides aren’t going to get anything. Angles are going to be wrong and people prefer to park their cars in the shade or under cover. Cars also tend to be used, so they get pretty dirty driving around, that reduces efficiency further. So if they get half of what I described, they would be doing real good. Just takes a week to charge the car, but still, doing good.

    But then there’s the real kicker. It isn’t possible to get anywhere near 20% out of a paint or surface finish. Modern solar panels have many tricks to get their efficiency as high as 20% (and even nearing 30% with the newest techniques, but that isn’t commercially viable at the moment). Solar paints are way worse and do badly even in perfect lab settings. One of the issues is the energy generation isn’t as optimal to begin with, but another issue is getting the energy transported out of the material is problematic. This leads to efficiency numbers in the 1% range. This means going from charging in a week, it will take months, if it charges at all.

    Except for niche use cases, putting solar on anything except roofs usually makes no sense at all. It’s handy for camping, on top of the RV or for example on a boat, where having a little bit of DC is handy when no other sources is available. But when there is a roof available, just put it on the roof and use the power from there.



  • Yes.

    Even in a unjust world mob justice isn’t justice. This means a mob deciding someone is guilty and acting out punishment is unjust. But also a mob deciding a crime should go unpunished is unjust.

    There’s plenty wrong with how insurance works and plenty wrong with the justice system. But instead of giving up, we should be trying to fix these issues. It’s all to easy to give in to our basic instincts and point to someone to blame. We punish them instead of fixing the issues. Killing one ceo might feel good, but it doesn’t really change the big picture and in fact constitutes layer upon layer of failure. We should be better than that. History is full of people (singular and groups) being used as a scape goat to deflect and feel like something is being done, whilst in fact not actually fixing anything and just feeding hate.

    Also in a capitalist world, the people with the most money have the most power. If we collectively decide it’s open warfare, purge style distopia, they are going to have the upper hand. So purely from a self interest point of view, it would be better to work on fixing shit instead of reverting to monke.





  • I like the online part just fine, but it feels like a completely different game. When I play offline, it’s like I’m in the world of the Lands Between. I’m myself on an epic quest, even though I have a meme name and a meme face. When playing online it’s like I’m playing a video game where my character does things.

    I usually prefer to play offline, even though I like the online parts.

    And I love playing seamless coop with a friend, it’s like going on an epic quest together.



  • You say that, but without the US military support it will be rough for Ukraine. The EU has spent a bunch of money to get all other kinds of aid to Ukraine, much more than the US. But the US has supplied more military support, more than the EU. If the US stops helping out, the EU will probably not be able to fill the gap. And Trump can put pressure on the EU by threatening to pull out of Nato again. If Russia decides to invade more countries and the US leaves Nato hanging, the EU is in trouble. Now these are a lot of ifs and since Trump has been elected the EU has been preparing. Plus laws have been passed in the US to prevent Trump from pulling out of Nato, but you know how much Trump cares about laws. Once the EU feels like they don’t need the support from the US any more, Trump has nothing to say anymore, but we ain’t there yet.







  • We always put a couple of bells on the bottom of the tree. Because they are shiny and round, the cats always go for them first. This alerts us and we can verbally berate them for messing with the tree. This works most of the time to keep them in check. Even when I’m upstairs and I hear the bells I call down: “I know what you are doing” and they slink off. Sometimes they just ignore me and play with the tree anyways, which is fine because the bottom row is all plastic balls they can play with as much as they like.

    I remember the first time one of our cats saw a Christmas tree, when he was a little kitten. I turned around for 10 secs, looked back and he was sitting proud on top of the tree. I laughed my ass off, until he realized he had no real way of getting down. So I laughed some more and fetched him off the tree. Good to get it out of the system I think, because he didn’t try that again.