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Lurking Haro posted:It's the equivalent of pulling the gas hose over your car because you forgot where your gas tank is. Though the benefit there is that you don't keep the car there for 15 minutes. Also you'd think that one of the benefits of an EV is you can put charger ports on both sides/ends of the car. Though I guess some dumbass would try plugging all of them in at once if you did that.
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Jun 21, 2018 21:39
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Trabisnikof posted:In the US you see slightly more CHAdeMO chargers than CCS, and globally far more CHAdeMO vehicles have been sold. Most of the time I see HVDC stations with both CCS and CHAdeMO here, which makes sense really since that covers almost all of the EV fleet for the cost of an additional cable. Chademo is a Japanese standard and I think the only two cars in the US that use it are the Japanese Nissan Leaf (over 100k of them in US, though a minority have Chademo) and the Mitsubishi i-MIEV (something like 2000 cars sold in U.S. in one decade, lol) J1772 Combo is relatively new and there's no reason it shouldn't greatly eclipse Chademo in the US in the coming years. OwlFancier posted:Also you'd think that one of the benefits of an EV is you can put charger ports on both sides/ends of the car. Funny you mention that, I built a custom EV that uses two J1772 chargers, one on each side, and if I plug them both in (with two adjacent cords at a charging station) then I'll actually charge twice as fast (charge controller supports parallel), 13.2kw total.
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Jun 21, 2018 21:43
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I would guess a normal tesla would just catch fire if you did that though? I assume they don't build them for significantly more capacity than the cables can carry?
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Jun 21, 2018 21:46
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OwlFancier posted:I would guess a normal tesla would just catch fire if you did that though? I assume they don't build them for significantly more capacity than the cables can carry? The EVs I've worked on monitor current, voltage, temperature and more. If anything is out of specs, it stops charging. A resistor in the cable even tells the car what current it can pull. Redundant ports would likely all go to the same internal charger anyway and to avoid having the other ones live, they would have to be switched, too. Worst case I can imagine is someone plugging in multiple cables with switched polarity/phases, creating a short. -e- Charging stations are just high power power outlets. The car has the charger on-board.
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Jun 21, 2018 21:57
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Zero VGS posted:Chademo is a Japanese standard and I think the only two cars in the US that use it are the Japanese Nissan Leaf (over 100k of them in US, though a minority have Chademo) and the Mitsubishi i-MIEV (something like 2000 cars sold in U.S. in one decade, lol) Yeah but its the standard that pretty much all the major Japanese car brands (including Toyota) are supporting and the way IEC 62196 is laid out, I think we'll see continued support for both in the US. https://en.wikipedia.org/wiki/IEC_62196 Especially since the non-tesla auto manufacturers are have started installing both at their charging stations, Nissan, BMW and VW are all installing both at their HVDC stations.
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Jun 21, 2018 21:59
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OwlFancier posted:I would guess a normal tesla would just catch fire if you did that though? I assume they don't build them for significantly more capacity than the cables can carry? If you added a second charge cable, the ampacity would be spread between the left and right side charge wiring (the wiring between the charge inlet, and the high voltage junction box). The junction box has very robust busbars/contactors and could probably handle a stupid amount of juice. After that is the liquid cooled AC to DC charger (which is bypassed if you're using a Super Charger, as those are DC), and existing Teslas can actually have two AC to DC chargers in parallel as an upgrade option (this would not affect supercharger speed, just home AC charging speed). But yes, if Tesla wanted to build for it, it would be trivial to double or quadruple the inlets on a car. That battery has the C rating to handle it. Some pics of the Tesla Semi from the unveiling showed that the prototype is simply using a quadruple inlet. Also interesting is that to make a Tesla supercharger, they take the same liquid cooled AC to DC converted that the Model S has one or two of, and they stack something like 8 of them together inside the charging station, so your car can accept the huge level of DC without having to convert it onboard. Zero VGS fucked around with this message at 22:05 on Jun 21, 2018 |
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Jun 21, 2018 22:03
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I'm not really sure where to ask, but since there are industry goons in the thread I feel this is as good as any: anyone know how the DoE has been fairing under Perry? The lack of scandals actually has me more nervous with that slimy gently caress than if he'd already screwed the pooch.
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Jun 28, 2018 23:54
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First good TED talk I've seen in awhile: https://www.youtube.com/watch?v=7a5NyUITbyk It's basically about a metamaterial that radiates infrared in the range that passes through the atmosphere into space well, while also reflecting sunlight frequencies. It can keep things cooler than atmospheric ambient temperature, even in direct sunlight. That's just... amazing.
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Jul 1, 2018 22:56
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crazypenguin posted:metamaterial I think 'optical filter' would be a better & more precise term to use to describe the scientist's work. Using the term 'meta-material' probably helps him hype up his research to get money from government funding agencies, however . . . Optical filters are pretty common and have been around for a while. The idea of designing an optical filter to improve the efficiency of radiative cooling of an object to outer space during the daytime, which is what he and others did, might be novel though. crazypenguin posted:It's basically about a metamaterial that radiates infrared in the range that passes through the atmosphere into space well, while also reflecting sunlight frequencies. It can keep things cooler than atmospheric ambient temperature, even in direct sunlight. Yeah, it's pretty cool. I like the stuff about the ancients--it definitely makes for a pretty compelling story. I'm not really an HVAC engineer, but there are two things I suspect could be a problem with this work. The first is that the entire idea is dependent on heat transfer only taking place via thermal radiation. In order for this refrigeration scheme to really work well, he is obligated to totally thermally insulate his system from conductive & convective heat transfer. For a lot of applications, I'm not sure how practical this requirement is. The second is that it seems like he only has a small amount of cooling power or cooling capacity. I suspect that cooling power is a pretty important figure of merit for refrigeration systems, since it affects the time it takes to cool a (thermally) large object. The scheme is relying on thermal radiation of an object at around room temperatures into this kind of narrow band of infra-red frequencies in this window into outer space. I don't think that there is a lot of power there--it seems much much much more dilute than sunlight, and we already complain about sunlight not being as concentrated an energy source as we would like it to be. silence_kit fucked around with this message at 00:47 on Jul 2, 2018 |
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Jul 2, 2018 00:26
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crazypenguin posted:First good TED talk I've seen in awhile: Wow, you could make sheets of that stuff and stick peltier with heatsink (heatrise?) to the bottom for 24/7 reverse solar panels. I wonder how much power that could generate for the same surface area as photovoltaic. Even a small fraction might be useful if you depend on the constant output. Would cloud cover affect it adversely?
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Jul 2, 2018 01:10
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Dameius posted:I'm not really sure where to ask, but since there are industry goons in the thread I feel this is as good as any: anyone know how the DoE has been fairing under Perry? The lack of scandals actually has me more nervous with that slimy gently caress than if he'd already screwed the pooch. His office is interfering with the climate and renewable energy people and especially their ability to speak on their own without approval. The core functions remain intact, because he's be murked if he touched those.
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Jul 2, 2018 01:18
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Zero VGS posted:Wow, you could make sheets of that stuff and stick peltier with heatsink (heatrise?) to the bottom for 24/7 reverse solar panels. I wonder how much power that could generate for the same surface area as photovoltaic. Even a small fraction might be useful if you depend on the constant output. Would cloud cover affect it adversely? On a hunch I would say it being highly reflective yet emmisive is the more important point than radiating heat into space. Reflective surfaces are normally bad radiators and vice versa. Clouds are high up, so if they reflect this band, it would be scattered over a wide area. I still doubt it would be efficient enough for energy generation since that requires high temperature gradients to be useful, but it would be great for making concrete deserts cooler.
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Jul 2, 2018 01:41
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Lurking Haro posted:On a hunch I would say it being highly reflective yet emmisive is the more important point than radiating heat into space. He made a great point about increasing solar panel efficiency too. The common flexible solar panels that are white backing with black solar cells perform at a certain level, while the ones that are made "black on black" for cosmetic reasons are less efficient because they absorb more heat like a black tee shirt, increasing resistance of the wires. There's some made with aluminum backing and they are the most efficienct due to having the best reflection (and the aluminum conducts the heat better). Coating the aluminum backing in this stuff before encapsulating the solar cells would give a huge boost in real world efficiency. Mass producing this as a thin optical filter foil might be a cost effective way to get some more efficiency out of solar. To the people wondering how it could improve air conditioning or be used passively, imagine a CPU heat sink. Flip it upside down so the CPU plate is facing up and the heat sink fins are facing down. Now scale it up to be 4 cubic feet or something, and install it in a roof so the fins are inside the house and the CPU plate is outside the house facing the sky, coated with this material. Warm air rises to the roof of the house, heats the fins to make the water inside the heat pipes rise to the cooling plate where it becomes cold and condenses, traveling back down to the fins where they exchange heat with the attic air, which being colder will cascade down the inside of the house. That would work 100% passively like a passive CPU heat sink, but in the same way as a CPU heatsink, involving fans and coolant pumps is going to accelerate the effect for negligible electricity increase.
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Jul 2, 2018 17:40
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Zero VGS posted:He made a great point about increasing solar panel efficiency too. The common flexible solar panels that are white backing with black solar cells perform at a certain level, while the ones that are made "black on black" for cosmetic reasons are less efficient because they absorb more heat like a black tee shirt, increasing resistance of the wires. There's some made with aluminum backing and they are the most efficienct due to having the best reflection (and the aluminum conducts the heat better). Coating the aluminum backing in this stuff before encapsulating the solar cells would give a huge boost in real world efficiency. Mass producing this as a thin optical filter foil might be a cost effective way to get some more efficiency out of solar. This refrigeration scheme only works if the filter and object to be cooled is pointing at the sky or if the 10um wavelength ray reflections off of the ground eventually make it to the night sky. You’d have to paint the ground underneath the solar cells ‘white’ or use a metallic reflector for this to work. Zero VGS posted:To the people wondering how it could improve air conditioning or be used passively, imagine a CPU heat sink. Flip it upside down so the CPU plate is facing up and the heat sink fins are facing down. Now scale it up to be 4 cubic feet or something, and install it in a roof so the fins are inside the house and the CPU plate is outside the house facing the sky, coated with this material. Warm air rises to the roof of the house, heats the fins to make the water inside the heat pipes rise to the cooling plate where it becomes cold and condenses, traveling back down to the fins where they exchange heat with the attic air, which being colder will cascade down the inside of the house. That would work 100% passively like a passive CPU heat sink, but in the same way as a CPU heatsink, involving fans and coolant pumps is going to accelerate the effect for negligible electricity increase. The only experimental demonstration of this refrigeration scheme involved them enclosing both the filter and the object to be cooled in a pretty high ~1 uTorr vacuum chamber. They really pulled out all of the stops to design their experiment to enhance the temperature differential by building the equivalent of ‘a frictionless spherical cow.’ Any performance numbers from these experiments should be put into this context. Given the very weak cooling power and these pretty unpractical conditions, it might be very challenging to use this refrigeration scheme in a real system. silence_kit fucked around with this message at 00:03 on Jul 3, 2018 |
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Jul 2, 2018 18:16
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Has there been any discussion of the production cost of this file yet? The video has a mention that industrial level production facilities are already capable of producing it, but nothing on the actual cost. I would imagine that if it is cheap enough to add a negligible cost, it will increase the efficiency of various processes already in use. If it isn’t that inexpensive, it will probably only see very niche uses where every bit of cooling performance is needed.
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Jul 2, 2018 23:03
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Orvin posted:Has there been any discussion of the production cost of this file yet? The video has a mention that industrial level production facilities are already capable of producing it, but nothing on the actual cost. So there are a few commingled teams working on this same basic tech, which from what I read is based on thin layers of silicon and other elements: https://news.stanford.edu/2017/09/04/sending-excess-heat-sky/ So there’s already one company attempting commercialization: http://skycoolsystems.com They claim to be able to chill water to 5C below ambient air temp with no water loss and only pumping energy. So something that theoretically could be useful, but I’m highly highly skeptical the integration costs are worth it. Like maybe process water pre-chillers, but generally 5 degrees below ambient roof temperatures still needs more chilling to be useful. In general I’m skeptical of the ability for these high intensity technological solutions to beat boring efficiency opportunities when we example the scale of changes the technology requires for integration.
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Jul 2, 2018 23:13
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Zero VGS posted:Funny you mention that, I built a custom EV that uses two J1772 chargers, one on each side, and if I plug them both in (with two adjacent cords at a charging station) then I'll actually charge twice as fast (charge controller supports parallel), 13.2kw total. Edit: that TED talk was real interesting. I’d call that material a selective surface, which is what the inverse is called in solar thermal applications where they design for high emissivity/absorptivity in the visible spectrum but low emissivity/absorptivity in the infra red. bawfuls fucked around with this message at 02:35 on Jul 3, 2018 |
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Jul 3, 2018 01:14
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silence_kit posted:This refrigeration scheme only works if the filter and object to be cooled is pointing at the sky or if the 10um wavelength ray reflections off of the ground eventually make it to the night sky. You’d have to paint the ground underneath the solar cells ‘white’ or use a metallic reflector for this to work. I'm talking about the top of the solar panels. Here's a white, black, and polished aluminum solar panel respectively:  The black-on-black gets the hottest, while the white is cooler and the aluminum is cooler still. If you could make a thin foil of this filter to go on top of the aluminum it could lower the temps further. Even a few degrees would make a huge difference for a solar farm. I still don't get why it has to be sky-facing exactly... do the infrared light rays have to be aimed into space for the heat to "flow" away? If you aim them 100 feet down the street into some bushes, it won't work the same? silence_kit posted:The only experimental demonstration of this refrigeration scheme involved them enclosing both the filter and the object to be cooled in a pretty high ~1 uTorr vacuum chamber. Given the very weak cooling power and these pretty unpractical conditions, it might be very challenging to use this refrigeration scheme in a real system. Vacuum chambers are used extensively for solar water heating: https://en.wikipedia.org/wiki/Solar_water_heating So maybe a variation on that? To cool water down and pump it to a heat exchanger elsewhere, like a mini split air conditioner. Zero VGS fucked around with this message at 02:47 on Jul 3, 2018 |
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Jul 3, 2018 02:42
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Zero VGS posted:I still don't get why it has to be sky-facing exactly... do the infrared light rays have to be pointed as space for the heat to "flow" away? If you aim them 100 feet down the street into some bushes, it won't work the same?
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Jul 3, 2018 02:46
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Zero VGS posted:I still don't get why it has to be sky-facing exactly... do the infrared light rays have to be aimed into space for the heat to "flow" away? If you aim them 100 feet down the street into some bushes, it won't work the same? Because it is relying on the radiating sky for the cooling: https://en.wikipedia.org/wiki/Radiative_cooling quote:Radiative cooling is commonly experienced on cloudless nights, when heat is radiated into space from the surface of the Earth, or from the skin of a human observer. The effect is well-known among amateur astronomers, and can personally be felt on the skin of an observer on a cloudless night. To feel the effect, one compares the difference between looking straight up into a cloudless night sky for several seconds, to that of placing a sheet of paper between one's face and the sky. Since outer space radiates at about a temperature of 3 kelvins (-270 degrees Celsius or -450 degrees Fahrenheit), and the sheet of paper radiates at about 300 kelvins (room temperature), the sheet of paper radiates more heat to one's face than does the darkened cosmos. The effect is blunted by Earth's surrounding atmosphere, and particularly the water vapor it contains, so the apparent temperature of the sky is far warmer than outer space. Note that it is not correct to say that the sheet "blocks the cold" of the night sky; instead, the sheet is radiating heat to your face, just like a camp fire warms your face; the only difference is that a campfire is several hundred degrees warmer than a sheet of paper, just like a sheet of paper (at approximately air temperature) is warmer than the night sky. There is a very long history of using this cooling effect: https://misfitsarchitecture.com/2013/03/01/its-not-rocket-science-5-night-sky-radiant-cooling/
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Jul 3, 2018 03:05
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bawfuls posted:I’d call that material a selective surface, which is what the inverse is called in solar thermal applications where they design for high emissivity/absorptivity in the visible spectrum but low emissivity/absorptivity in the infra red. Oh yeah, you are right, filter might not really be the right word either since filters are usually, but not always, reflective or purely reactive and the term kind of implies that they are a two port device with transmission. I guess you could call it a dual-band, absorptive band stop filter along with a reactive band pass filter, designed to be used with one side short circuited. Admittedly that is kind of a mouthful. ‘Meta-material’ is definitely a category error though. silence_kit fucked around with this message at 04:08 on Jul 3, 2018 |
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Jul 3, 2018 03:44
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OK, I think I can finally wrap my head around it. It's not that you're aiming your own infrared light into a certain direction for it to leave (though nearby things can reflect some back); it's that you're facing the thing that is sending the least amount of infrared light towards you, which in this case would be space. It would be like turning away from a campfire to cool off if your face felt too hot from looking directly towards it. Space is sending basically no infrared light at all, where anything on Earth would be comparatively orders of magnitude hotter. Thanks for explaining!silence_kit posted:Oh yeah, you are right, filter might not really be the right word either since filters are usually, but not always, reflective or purely reactive and the term kind of implies that they are a two port device with transmission. I guess you could call it a dual-band, absorptive band stop filter along with a reactive band pass filter, designed to be used with one side short circuited. That Wiki entry for radiative cooling up above mentions the optical thing and also calls it a "meta-material", which has it's own entry that technically fits the description, though I agree it is more precise to call it an optical filter.
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Jul 3, 2018 08:48
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Zero VGS posted:I still don't get why it has to be sky-facing exactly
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Jul 4, 2018 23:10
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evil_bunnY posted:It doesn't, but whatever catches the reflected gets heated up. So if that's a distant asteroid, that's very much not-your-problem, but a nearby building might be. bawfuls fucked around with this message at 18:36 on Jul 5, 2018 |
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Jul 5, 2018 18:34
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bawfuls posted:No, it does need to face space (or the coldest thing possible). Whatever it's facing is also going to be radiating back at it. If the panel is facing a nearby building, then the building is going to radiate heat to the panel based on it's ambient temperature, somewhere around 300 K. If the panel is facing space, then space is radiating heat to the panel based on an ambient temperature ~3 K. Thermal radiation is a function of T^4, that's Temperature to the fourth power. The difference in radiative energy received by the panel facing a 300K building vs 3K space is about 7 orders of magnitude.
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Jul 5, 2018 19:53
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Infinite Karma posted:Educate me: why is it facing "space" and not facing "50+ miles of atmosphere" if it's pointed at the sky? Doesn't air have thermal temperature + density well above the 3 K background temperature? And likewise, doesn't the angular size and distance of the radiation source matter for how much of that thermal energy is transferred? You’re correct it has an effect and that’s why it doesn’t work under the clouds, but space is very cold: quote:Since outer space radiates at about a temperature of 3 kelvins (-270 degrees Celsius or -450 degrees Fahrenheit), and the sheet of paper radiates at about 300 kelvins (room temperature), the sheet of paper radiates more heat to one's face than does the darkened cosmos. The effect is blunted by Earth's surrounding atmosphere, and particularly the water vapor it contains, so the apparent temperature of the sky is far warmer than outer space. Note that it is not correct to say that the sheet "blocks the cold" of the night sky; instead, the sheet is radiating heat to your face, just like a camp fire warms your face; the only difference is that a campfire is several hundred degrees warmer than a sheet of paper, just like a sheet of paper (at approximately air temperature) is warmer than the night sky.
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Jul 5, 2018 19:56
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Which is also why it's very cold on a cloudless night.
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Jul 5, 2018 19:57
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I know that space is very cold. But I also know that the atmosphere is not. It seems like you should be calculating the thermal radiative exchange based primarily on the atmosphere's temperature and attenuation, not on the lower temperature of space that's behind it.
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Jul 5, 2018 20:11
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The temperature of the atmosphere is going to vary based on its composition at the time and your altitude, however. But the general idea is that it's always going to be colder than the planet.
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Jul 5, 2018 20:25
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Infinite Karma posted:I know that space is very cold. But I also know that the atmosphere is not. Radiated power isn't just based on the 4th power of temperature, it's also based on the emissivity of the material. A perfect blackbody has an emissivity of 1. Emissivity of air is much lower. Much of the atmosphere *is* cold, and of the bits that aren't cold they don't emit much in the way of thermal radiation. Air at a temperature of 70 degrees F will radiate much less energy than a chunk of 70F asphalt.
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Jul 5, 2018 20:39
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Infinite Karma posted:I know that space is very cold. But I also know that the atmosphere is not. It seems like you should be calculating the thermal radiative exchange based primarily on the atmosphere's temperature and attenuation, not on the lower temperature of space that's behind it. I guess the idea is that clouds reflect a good deal of infrared light back to the planet, as well as having their own infrared light (clouds would be cold but still contain heat), compared to space which doesn't really reflect any infrared light nor generate it's own. Get a load of this, straight from the Nasa website. Apparently you can use a fuckin' $10 infrared thermometer to measure a cloud vs the rest of the sky, mind blown: https://mynasadata.larc.nasa.gov/science_projects/measuring-the-temperature-of-the-sky-and-clouds/  Edit: the Nasa article also very clearly explains the water vapor effect that people here were asking about too. It does definitely reflect some heat, but not in the wavelength that the TED talk called the "transmission window", which is what they're exploiting: https://en.wikipedia.org/wiki/Infrared_window Zero VGS fucked around with this message at 20:54 on Jul 5, 2018 |
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Jul 5, 2018 20:44
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Zero VGS posted:
That difference is precisely because of the differing emissivity. When you point one of those thermometers at something, it's measuring the infrared energy incident on the sensor and assuming that what you're pointing it at is something close to a blackbody (emissivity=1), and calculating how hot that thing would be to be giving off that much energy. The emissivity of air is nothing like that of a blackbody. A cloud isn't very close to one either, but it's much closer to one than the air is. So even though that cloud is probably more or less in thermal equilibrium with the air it's floating in, the thermometer is showing two very different temperatures.
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Jul 5, 2018 21:06
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Infinite Karma posted:I know that space is very cold. But I also know that the atmosphere is not. It seems like you should be calculating the thermal radiative exchange based primarily on the atmosphere's temperature and attenuation, not on the lower temperature of space that's behind it. bawfuls fucked around with this message at 21:36 on Jul 5, 2018 |
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Jul 5, 2018 21:30
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bawfuls posted:Because the atmosphere is largely transparent to the wavelengths of radiation being considered here. It participates to a small degree, as Phanatic touched on. You're right that it makes very little difference because the sky doesn't radiate much heat (unless you're an infrared astronomer, then it loving emits too much and sucks) but he's right in pointing out that the sky is going to emit *some* thermal radiation, even if it's a small amount. He's overstating the effect but yeah
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Jul 6, 2018 05:57
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This is incredibly cool. Enphase microinverters starting next year are going to be able to keep a house powered during the daytime even if the grid is down without batteries. https://runonsun.com/~runons5/blogs/blog1.php/residential-solar/what-i-saw-at-enphase-mind-blown Likely requires an automatic transfer switch of some kind with current transformers and only sub panels downstream of the transfer switch will be able to be powered. Batteries can be added as well to continue powering if the solar isn't producing enough but don't have to be. And it's going to be backwards compatible with the last couple generations of Enphase microinverters.
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Aug 18, 2018 01:16
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fermun posted:This is incredibly cool. Enphase microinverters starting next year are going to be able to keep a house powered during the daytime even if the grid is down without batteries. I'm curious how this works at the end of the blackout. Assuming it had some grid protections and anti-islanding regulations were overcome, how does it resync to grid ac? Does it just require shutting down the island and bringing it back on grid or does it do something fancier to sync frequency?
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Aug 18, 2018 22:36
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Trabisnikof posted:I'm curious how this works at the end of the blackout. Assuming it had some grid protections and anti-islanding regulations were overcome, how does it resync to grid ac? Does it just require shutting down the island and bringing it back on grid or does it do something fancier to sync frequency? Shouldn’t be hard if it’s all solid state? Use an ADC to measure the phase, frequency and voltage* of the mains side, have your inverter match that then throw the relay. The trick is getting the power company to trust the lives of their linemen to your system. *from my power systems lab I remember there are three things that have to be the same to connect two AC systems together but I’m not 100% that these are those things
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Aug 18, 2018 23:21
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hobbesmaster posted:Shouldn’t be hard if it’s all solid state? Use an ADC to measure the phase, frequency and voltage* of the mains side, have your inverter match that then throw the relay. The trick is getting the power company to trust the lives of their linemen to your system. I’m not sure how devices inside the house would handle having the phase shifted without cutting the power. Might make some motors pretty angry.
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Aug 19, 2018 00:13
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Wait, I’m confused. Don’t solar power systems in areas that have net metering have to automatically decouple in the event of power failures already? And if you’re feeding excess power back to the grid, don’t those systems have to already sync phase?
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Aug 19, 2018 04:37
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Phanatic posted:Wait, I’m confused. Don’t solar power systems in areas that have net metering have to automatically decouple in the event of power failures already? And if you’re feeding excess power back to the grid, don’t those systems have to already sync phase? Yes. But if you put an automated transfer switch in (like you would with a generator or backup battery) you could decouple from the grid without shutting down production. Enphase's trick is to maintain voltage stability in the face of rapidly shifting loads without the 'infinite stability' sink of a grid connection. It'll work a lot better with a battery - but since their own batteries use their normal microinverters they might as well have Ensemble work everywhere anyways.
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Aug 19, 2018 05:34
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