CaptainPanic Posted October 17, 2011 Posted October 17, 2011 In theory on Earth to minimize friction you just need to make the blades heavier and bigger, but the problem is that the wind wouldn't be strong enough to spin them. In space all these problems would be gone. Big and heavy is a HUGE problem in space... LOL. Right now, we need to lift everything off this planet (with rockets). I think you are not just thinking about giant wind turbines in space, but also about asteroid mining, space factories, efficient and large cargo space ships with unlimited Star Trek energy systems, and in general a huge space economy, similar to the Earth's economy, but then without gravity. But if we would have such a huge space economy, then it would still be more efficient to build the wind turbines on the land on earth (and the reason was explained in my previous post).
CaptainPanic Posted October 17, 2011 Posted October 17, 2011 SBSP FTW. What? I don't know what that means. Can you please write in English, and also explain your argument if you wish to participate in the discussion? 3
Myuncle Posted October 17, 2011 Author Posted October 17, 2011 Big and heavy is a HUGE problem in space... LOL. Right now, we need to lift everything off this planet (with rockets). I think you are not just thinking about giant wind turbines in space, but also about asteroid mining, space factories, efficient and large cargo space ships with unlimited Star Trek energy systems, and in general a huge space economy, similar to the Earth's economy, but then without gravity. But if we would have such a huge space economy, then it would still be more efficient to build the wind turbines on the land on earth (and the reason was explained in my previous post). Don't allow media to brainwash you. Big and heavy is a HUGE problem only for the oil companies. If all the money we waste in oil was invested in space economy it would be better for all of us. If all the nations want to do it they could collaborate easily, energy it's in the interest of the majority of the whole planet, but it's not in the interest of a small minority of rich entrepreneurs.
CaptainPanic Posted October 17, 2011 Posted October 17, 2011 (edited) Don't allow media to brainwash you. Big and heavy is a HUGE problem only for the oil companies. If all the money we waste in oil was invested in space economy it would be better for all of us. If all the nations want to do it they could collaborate easily, energy it's in the interest of the majority of the whole planet, but it's not in the interest of a small minority of rich entrepreneurs. What?????????? LOL. Ok... please calculate for me the kinetic energy required to get 1 kg of construction material into orbit. LEO (Low Earth Orbit). Thanks. Why do you think you need a huge rocket to get a tiny little space craft into space? You think that's a conspiracy theory? There's really no brainwashing here... just simple physics. Edited October 17, 2011 by CaptainPanic
Xittenn Posted October 17, 2011 Posted October 17, 2011 In concept at least, solar sails do not weigh much of anything. Also for all intents and purposes we have no use for such technology, but you never know when something like this will come in handy. I guess it would come down to there being a lot more space in space, and it would also be an incorporated system that included light and charge harnessing. I find it hard to believe that this will never be a real project given the continued growth of humanity. The value of 2mW/m^2 might change some day. On a side note, it's funny that we look for the stars that might have life in orbit. Maybe we should look for the missing stars . . . . [star trek music here]
Myuncle Posted October 17, 2011 Author Posted October 17, 2011 The ISS is kind of heavy, it's the size of a football field and it has been a success, if they didn't have any problem with assembling the components I don't see why assembling the turbines would be more difficult, actually it would be easier. There have been 135 launches to the space station since the launch of the first module (by the way the 90 kilowatts of power for the ISS is supplied by solar panels). You can simply send on space sections of gigantic blades ready to assemble and spin at incredible speed generating lots of power, this is not Star Trek. For the space station they spent more or less $100 billion, which is nothing if you compare it with all the money we spend in oil and energy bills.
InigoMontoya Posted October 18, 2011 Posted October 18, 2011 The ISS is kind of heavy, it's the size of a football field and it has been a success, if they didn't have any problem with assembling the components I don't see why assembling the turbines would be more difficult, actually it would be easier. There have been 135 launches to the space station since the launch of the first module (by the way the 90 kilowatts of power for the ISS is supplied by solar panels). You can simply send on space sections of gigantic blades ready to assemble and spin at incredible speed generating lots of power, this is not Star Trek. For the space station they spent more or less $100 billion, which is nothing if you compare it with all the money we spend in oil and energy bills. But at what cost? Even if getting something into LEO cost 1/50 of what it does today... Even if you could get the exact same efficiency from your space based windmill.... you're STILL spending an enormous amount of energy to replicate what can be easily done on Earth's surface. And if it breaks, who's going to fix it? On Earth it's easy to just send a guy up to fix it. In space... Not so much. 1
the asinine cretin Posted October 18, 2011 Posted October 18, 2011 What? I don't know what that means. Can you please write in English, and also explain your argument if you wish to participate in the discussion? let me google that for you, 4$$|-|@ /\/\(DB49. this is teh interwebs biatch. SBSP FTW -4
CaptainPanic Posted October 18, 2011 Posted October 18, 2011 The ISS is kind of heavy, it's the size of a football field and it has been a success, if they didn't have any problem with assembling the components I don't see why assembling the turbines would be more difficult, actually it would be easier. There have been 135 launches to the space station since the launch of the first module (by the way the 90 kilowatts of power for the ISS is supplied by solar panels). You can simply send on space sections of gigantic blades ready to assemble and spin at incredible speed generating lots of power, this is not Star Trek. For the space station they spent more or less $100 billion, which is nothing if you compare it with all the money we spend in oil and energy bills. Ok, so for 100 billion euro/dollar, you can get maybe 100 wind turbines the size of a football field (assuming they are somehow super light weight, and even 100 times lighter than the space station which is already light weight)? A regular wind turbine on earth costs about 2 million each (so, 100 of them costs 200 million)... In other words: Even if you make super lightweight wind turbines in space, they are at least 50 times more expensive... and at least 20,000 times less efficient (see previous post for efficiency explanation). So, per generated kWh of energy, they are at least 1,000,000 times as expensive. And that's being really optimistic. let me google that for you, 4$$|-|@ /\/\(DB49. this is teh interwebs biatch. SBSP FTW No, this is SFN, scienceforums.net... not just "teh interwebs". Here we write in English, and we try to make sense... You are too lazy to write 7 words in full, but at the same time you expect other people to go to Google, look up two different abbreviations, then see how that links to the discussion in the thread (when it does not, because it's off topic - and you provide absolutely no argumentation to link it to the discussion)? That's not how this works... Anyway, I am happy you provided some additional information for the discussion. 1
the asinine cretin Posted October 18, 2011 Posted October 18, 2011 (edited) No, this is SFN, scienceforums.net... not just "teh interwebs". Here we write in English, and we try to make sense... You are too lazy to write 7 words in full, but at the same time you expect other people to go to Google, look up two different abbreviations, then see how that links to the discussion in the thread (when it does not, because it's off topic - and you provide absolutely no argumentation to link it to the discussion)? That's not how this works... Anyway, I am happy you provided some additional information for the discussion. I love you too. Hugs and Kisses, a lol kitteh P.S. How dare you give me a -1 just after I received my first +1... I'm heartbroken right now... But I forgive you, for that is love. Edited October 18, 2011 by Ceti Alpha V
Klaynos Posted October 18, 2011 Posted October 18, 2011 ! Moderator Note Please try and add something to the topic.And back on topic now.
the asinine cretin Posted October 18, 2011 Posted October 18, 2011 (edited) Yesss mastah... I hereby draw attention to space-based solar power. It is very interesting and there are companies and governments looking into it as we speak. I think it is awesome. Here is a wikipedia article about it. Wiki: SBPS In my fantasy life I couple SBSP with the possibility of in-situ lunar manufacturing of photovoltaics (e.g., the work of Geoffrey Landis of Glenn Research Center, here, and here). Perhaps in the not-too-distant future lunar manufacturing and the deployment of vast space-based solar arrays will be real. CaptainP(sp?), I did it for you. I made this post to show that I'm sincere. I care. I salute you! Edited October 18, 2011 by Ceti Alpha V
tom.redy Posted October 18, 2011 Posted October 18, 2011 The ISS is kind of heavy, it's the size of a football field and it has been a success, if they didn't have any problem with assembling the components I don't see why assembling the turbines would be more difficult, actually it would be easier. There have been 135 launches to the space station since the launch of the first module (by the way the 90 kilowatts of power for the ISS is supplied by solar panels). You can simply send on space sections of gigantic blades ready to assemble and spin at incredible speed generating lots of power, this is not Star Trek. For the space station they spent more or less $100 billion, which is nothing if you compare it with all the money we spend in oil and energy bills. read #15 how you will spin at incredible speed to generating lots of power?????
mooeypoo Posted October 18, 2011 Posted October 18, 2011 let me google that for you, 4$|-|@ /\/\(DB49. this is teh interwebs biatch. SBSP FTW RULEZ FTW YO \m/ I HAZ RULEZES. And a translated version: ! Moderator Note Let me remind you that we have rules of conduct, and we're serious about them. Personal attacks and ridicule not only will not fly, it will get you on a giant wind turbine out of this forum. Don't do that again.
Myuncle Posted October 18, 2011 Author Posted October 18, 2011 (edited) read #15 how you will spin at incredible speed to generating lots of power????? I explained already in #25, it's all about friction, you just need to kick-start the rotation, the turbine will spin at incredible speed, before slowing down it will take ages, and with all the energy generated you just use a tiny amount of it to keep the blades up to speed...(just saying, I am not sure of it). Edited October 18, 2011 by Myuncle
InigoMontoya Posted October 18, 2011 Posted October 18, 2011 I explained already in #25, it's all about friction, you just need to kick-start the rotation, the turbine will spin at incredible speed, before slowing down it will take ages, and with all the energy generated you just use a tiny amount of it to keep the blades up to speed...(just saying, I am not sure of it). And that is quite patently a false statement. True, there may not be frictional forces, but to extract energy from the system, you must... Well, extract energy from the system. Where do you think that energy comes from? Your spinning blades. So even if your blades are spinning at Ludicrous Speed, the moment you start to actually generate power with your system they will quickly grind to a halt. UNLESS... You are constantly feeding more energy back into the system. A wind turbine does this by extracting energy from the wind (yes, the wind on the back side of a turbine will be slightly slower than the wind on the front side). Your solar sail turbine... Well, yes, it is getting energy from the solar wind, but the energy density is crap (as has already been addressed in this thread) so you're unlikely to be getting maintainable energy levels at useful levels.
Xittenn Posted October 18, 2011 Posted October 18, 2011 The thought of flywheel energy driven by photo-ionization has always seemed to me like a good idear. +1 for photo-ionization driven flywheels I have design specifications in mind, but I do not wish to share with the class. Mostly because I loath being told I'm wrong!
Myuncle Posted October 18, 2011 Author Posted October 18, 2011 And that is quite patently a false statement. True, there may not be frictional forces, but to extract energy from the system, you must... Well, extract energy from the system. Where do you think that energy comes from? Your spinning blades. So even if your blades are spinning at Ludicrous Speed, the moment you start to actually generate power with your system they will quickly grind to a halt. UNLESS... You are constantly feeding more energy back into the system. A wind turbine does this by extracting energy from the wind (yes, the wind on the back side of a turbine will be slightly slower than the wind on the front side). Your solar sail turbine... Well, yes, it is getting energy from the solar wind, but the energy density is crap (as has already been addressed in this thread) so you're unlikely to be getting maintainable energy levels at useful levels. Solar sail turbines? I have never written about it. Why you say that the energy density is crap, how big and heavy do you think the space turbines can be? As big as you want! How powerful they can be? (I don't know). Weight, friction and mass is not a problem, the absence of gravity is energy itself. Our planet is spinning from millions of years, it's pretty heavy and doesn't give any problem. The energy required to kickstart the rotation can come from rockets at the end of the blades, not necessarily from the turbine. The thought of flywheel energy driven by photo-ionization has always seemed to me like a good idear. +1 for photo-ionization driven flywheels I have design specifications in mind, but I do not wish to share with the class. Mostly because I loath being told I'm wrong! Well, I don't have any design specifications in mind so I can share with no problem...
Xittenn Posted October 18, 2011 Posted October 18, 2011 Our planet is spinning from millions of years, it's pretty heavy and doesn't give any problem. Nothing is trying to convert the energy stored in the rotation of the earth to another form. Fundamental laws of physics state that energy cannot be created or destroyed. The second you try to use the energy stored in this spinning object, the object will slow down. You only get out what you put in. So whatever energy these rockets give the giant spinning space thingy, is the amount of energy that you will get out. Pretty basic concept . . . . . . The need for flywheels to be heavy, is to resist instant changes in their velocity or rotational speed. Flywheels are buffers on the drive train of vehicles not outer space energy sources . . . . unless of course it is a photo-ionization driven flywheel device \o/
InigoMontoya Posted October 18, 2011 Posted October 18, 2011 (edited) Solar sail turbines? I have never written about it. What would you call a spinning device that is driven by solar wind? I'd call it a solar sail turbine, but if you don't like that name, feel free to insert your preferred name for such a device. Alternatively, if you're saying that you are NOT describing some sort of generator set powered by rotating solar sails, then I apologize as there's been a misunderstanding somewhere. Why you say that the energy density is crap, how big and heavy do you think the space turbines can be? As big as you want! No, they can not be "as big as you want." And no, they can not be arbitrarily light either. In order to extract energy from the spinning device (whatever you want to call it), you have to exert a torque on that device. The larger the diameter of the device, the larger the stresses on all parts involved. That means that they DO have to have significant mass. True, that mass is still an order of magnitude below what an Earth-based system would be, but it's also a several orders of magnitude easier to throw that heavy Earth-based system on a truck and to the job site than it is to get that space-based system into a rocket and to LEO. How powerful they can be? (I don't know). Somebody on this thread already answered that: On the order of mW per square meter. Weight, friction and mass is not a problem, the absence of gravity is energy itself. Wrong. Mass (which drives weight) is a HUGE problem. You seem to be ignoring that you have to get this thing to space in the first place. Friction? OK, I'll grant you that one. Not that friction isn't real, but because it's such a minor part in this debate. As for the absence of gravity being energy itself? WTF? First off, being in orbit does NOT indicate a lack of gravity (quite the opposite, actually). Secondly, if this gizmo gets too big you're going to find that you're going to have all sorts of problems due to tidal forces. Third... The lack of gravity (even if it were true) is NOT an energy source. Our planet is spinning from millions of years, it's pretty heavy and doesn't give any problem. And the moment somebody starts using the Earth's rotational energy to generate a few PetaWatts, it WILL be a problem. Seriously, your statement is akin to somebody noting that a train doesn't slow down when a fly hits it's windshield. That doesn't mean the train isn't slowing down in general or that the fly didn't affect the train's velocity. Both statements are true. But the fly is so small that the effects are not easily measured. In sum: Yes, the Earth's rotation is slowing down.... But we're not going to notice any change in our lifetimes. The energy required to kickstart the rotation can come from rockets at the end of the blades, not necessarily from the turbine. So what? That's like saying you can drive from LA to NYC on a cup of gas simply because a cup of gas is enough to get you on the highway. What part of the law of Conservation of Energy are you not understanding? And if you don't understand the concept of the Conservation of Energy, I submit that you do not have the education to even begin to reasonably debate this topic. Edited October 18, 2011 by InigoMontoya
mooeypoo Posted October 18, 2011 Posted October 18, 2011 Nothing is trying to convert the energy stored in the rotation of the earth to another form. Fundamental laws of physics state that energy cannot be created or destroyed. The second you try to use the energy stored in this spinning object, the object will slow down. You only get out what you put in. So whatever energy these rockets give the giant spinning space thingy, is the amount of energy that you will get out. Pretty basic concept . . . . . . The need for flywheels to be heavy, is to resist instant changes in their velocity or rotational speed. Flywheels are buffers on the drive train of vehicles not outer space energy sources . . . . unless of course it is a photo-ionization driven flywheel device \o/ Also, the EArth's rotation is slowing down, *because* of energy expenditure. (see "Tidal Acceleration", which is usually negative acceleration [hence, deceleration]) Nothing is free, not even energy. What's expended, is transformed to something else, and is taken out of the system. That simple.
Myuncle Posted October 18, 2011 Author Posted October 18, 2011 (edited) What would you call a spinning device that is driven by solar wind? I'd call it a solar sail turbine, but if you don't like that name, feel free to insert your preferred name for such a device. Alternatively, if you're saying that you are NOT describing some sort of generator set powered by rotating solar sails, then I apologize as there's been a misunderstanding somewhere. No, they can not be "as big as you want." And no, they can not be arbitrarily light either. In order to extract energy from the spinning device (whatever you want to call it), you have to exert a torque on that device. The larger the diameter of the device, the larger the stresses on all parts involved. That means that they DO have to have significant mass. True, that mass is still an order of magnitude below what an Earth-based system would be, but it's also a several orders of magnitude easier to throw that heavy Earth-based system on a truck and to the job site than it is to get that space-based system into a rocket and to LEO. Somebody on this thread already answered that: On the order of mW per square meter. Wrong. Mass (which drives weight) is a HUGE problem. You seem to be ignoring that you have to get this thing to space in the first place. Friction? OK, I'll grant you that one. Not that friction isn't real, but because it's such a minor part in this debate. As for the absence of gravity being energy itself? WTF? First off, being in orbit does NOT indicate a lack of gravity (quite the opposite, actually). Secondly, if this gizmo gets too big you're going to find that you're going to have all sorts of problems due to tidal forces. Third... The lack of gravity (even if it were true) is NOT an energy source. And the moment somebody starts using the Earth's rotational energy to generate a few PetaWatts, it WILL be a problem. Seriously, your statement is akin to somebody noting that a train doesn't slow down when a fly hits it's windshield. That doesn't mean the train isn't slowing down in general or that the fly didn't affect the train's velocity. Both statements are true. But the fly is so small that the effects are not easily measured. In sum: Yes, the Earth's rotation is slowing down.... But we're not going to notice any change in our lifetimes. So what? That's like saying you can drive from LA to NYC on a cup of gas simply because a cup of gas is enough to get you on the highway. What part of the law of Conservation of Energy are you not understanding? And if you don't understand the concept of the Conservation of Energy, I submit that you do not have the education to even begin to reasonably debate this topic. wat? You are intimidating me with that weapon. Edited October 18, 2011 by Myuncle -1
the asinine cretin Posted October 18, 2011 Posted October 18, 2011 (edited) -- Edited October 18, 2011 by Ceti Alpha V
InigoMontoya Posted October 19, 2011 Posted October 19, 2011 (edited) wat? You are intimidating me with that weapon. Huh? That's just a pic of me at the office (notice the white board in the background?). Granted, I work in a decidedly unusual office. Edited October 19, 2011 by InigoMontoya
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