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Post by Deleted on Oct 9, 2019 18:51:24 GMT
And there was me thinking that wind is generated by the effect of solar radiation heating up the surface of the Earth, and tides are formed by the combined gravitational effect of the sun and the moon. But solar eclipses are a sign of god's displeasure so don't mess with that shit.
In other alternative energy news, how about the possibility of mining the moon for an isotope called helium-3? This is apparently why the Chinese are so keen to get there.
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Post by Telemachus on Oct 9, 2019 22:50:06 GMT
And there was me thinking that wind is generated by the effect of solar radiation heating up the surface of the Earth, and tides are formed by the combined gravitational effect of the sun and the moon. But solar eclipses are a sign of god's displeasure so don't mess with that shit. In other alternative energy news, how about the possibility of mining the moon for an isotope called helium-3? This is apparently why the Chinese are so keen to get there. Wind is in part generated by the effect of solar radiation heating up the surface of the earth. But if the earth always presented the same fact to the sun (ie rotated once a year) there would be no winds. Just a very hot side and a very cold side. It is only because the earth rotates faster than once a year, that we have winds and weather Which is what I said.
Tides are formed by the combined gravitational effect of the sun and moon. But once again, if the earth rotated once a year there would be no gravitational tidal effect from the sun. And if the moon rotated around the earth at the same time as the earth rotated, likewise. It is only because these bodies rotate at different speeds that we have tides. If you extract the energy created by these differing rotational speeds, you inevitably are extracting energy from those rotational speeds and thus slowing them.
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Post by Telemachus on Oct 9, 2019 22:51:56 GMT
Anyway, wind turbines extract energy from the environment and that energy comes from a combination of the rotation of the earth, and the power of the sun. So some of the energy comes from slowing down the earthβs rotation. Same with tidal power. Give it a few hundred years and the Gretaβs great great granddaughter will be campaigning to stop the wind turbines that are slowing the earth. Mind you, think how much extra you could get done in a 25 hour day! While I find wind turbines aesthetically displeasing, and while I agree than energy can neither be created nor destroyed, I'd speculate that the effect you mention must be negligible compared to wind resistance caused by buildings, cliff faces etc. The effect is small, but of course wind turbines are specifically designed to extract the energy from the wind, as opposed to merely deflecting it. A forest doesn't extract much energy - the wind just flows over the top of it. What grates with me is calling it "renewable energy" when it is no such thing. No doubt when folk first invented burning coal and oil, they couldn't see that in the long run it would all end in tears.
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Post by Mr Stabby on Oct 10, 2019 9:05:19 GMT
While I find wind turbines aesthetically displeasing, and while I agree than energy can neither be created nor destroyed, I'd speculate that the effect you mention must be negligible compared to wind resistance caused by buildings, cliff faces etc. The effect is small, but of course wind turbines are specifically designed to extract the energy from the wind, as opposed to merely deflecting it. A forest doesn't extract much energy - the wind just flows over the top of it. What grates with me is calling it "renewable energy" when it is no such thing. No doubt when folk first invented burning coal and oil, they couldn't see that in the long run it would all end in tears. Where does the energy which keeps your glider aloft come from?
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Post by Telemachus on Oct 10, 2019 9:43:14 GMT
The effect is small, but of course wind turbines are specifically designed to extract the energy from the wind, as opposed to merely deflecting it. A forest doesn't extract much energy - the wind just flows over the top of it. What grates with me is calling it "renewable energy" when it is no such thing. No doubt when folk first invented burning coal and oil, they couldn't see that in the long run it would all end in tears. Where does the energy which keeps your glider aloft come from? Well to some extent it depends on which type of lift we are talking about. But I think the answer is much the same, a combination of solar heating and a planet rotating much faster than its orbital time. Although sometimes it does feel like it stays up by sheer will power and me pulling up on the stick! An interesting question has popped into my head - just how much power in kw or whatever, is required to keep it aloft? It is a heavy beast, its mass with 2 people is around 750kg. Rate of descent when flying slowly at say 60mph in still air (no lift), is 0.5m/s. So we have 750 x 9.8 (acceleration due to gravity) x 0.5 = 3.675kw. Or about 5 bhp. At 90mph the rate of descent is 1m/s so that would be 7.35kw. Yes I will eventually stop the planet revolving but I will have done quite a bit of flying by then, so who cares.
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Post by Jim on Oct 10, 2019 10:59:38 GMT
And there was me thinking that wind is generated by the effect of solar radiation heating up the surface of the Earth, and tides are formed by the combined gravitational effect of the sun and the moon. But solar eclipses are a sign of god's displeasure so don't mess with that shit. In other alternative energy news, how about the possibility of mining the moon for an isotope called helium-3? This is apparently why the Chinese are so keen to get there. Helium on the moon? Of course, that's where all the kiddies balloons end up when they float up to the sky. We are running out so it makes sense to fetch it back down.
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Post by Deleted on Oct 10, 2019 11:53:36 GMT
And there was me thinking that wind is generated by the effect of solar radiation heating up the surface of the Earth, and tides are formed by the combined gravitational effect of the sun and the moon. But solar eclipses are a sign of god's displeasure so don't mess with that shit. In other alternative energy news, how about the possibility of mining the moon for an isotope called helium-3? This is apparently why the Chinese are so keen to get there. Wind is in part generated by the effect of solar radiation heating up the surface of the earth. But if the earth always presented the same fact to the sun (ie rotated once a year) there would be no winds. Just a very hot side and a very cold side. It is only because the earth rotates faster than once a year, that we have winds and weather Which is what I said.
Tides are formed by the combined gravitational effect of the sun and moon. But once again, if the earth rotated once a year there would be no gravitational tidal effect from the sun. And if the moon rotated around the earth at the same time as the earth rotated, likewise. It is only because these bodies rotate at different speeds that we have tides. If you extract the energy created by these differing rotational speeds, you inevitably are extracting energy from those rotational speeds and thus slowing them.
Truly edifying stuff. One would hope it will take a while though. I like the windmills, they look better than cooling towers.
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Post by Deleted on Oct 10, 2019 11:54:57 GMT
And there was me thinking that wind is generated by the effect of solar radiation heating up the surface of the Earth, and tides are formed by the combined gravitational effect of the sun and the moon. But solar eclipses are a sign of god's displeasure so don't mess with that shit. In other alternative energy news, how about the possibility of mining the moon for an isotope called helium-3? This is apparently why the Chinese are so keen to get there. Helium on the moon? Of course, that's where all the kiddies balloons end up when they float up to the sky. We are running out so it makes sense to fetch it back down. "The moon has abundant supplies of helium-3, a light and non-radioactive fusion fuel that is virtually nonexistent here on Earth. Because the moon lacks an atmosphere and has been bombarded by solar winds containing helium-3 for billions of years, the moon has massive volumes of the isotope. Some estimates suggest there are at least 1.1 million metric tons of helium-3 on the lunar surface, enough to power human energy needs for up to 10,000 years."
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Post by Jim on Oct 10, 2019 12:29:58 GMT
Helium on the moon? Of course, that's where all the kiddies balloons end up when they float up to the sky. We are running out so it makes sense to fetch it back down. "The moon has abundant supplies of helium-3, a light and non-radioactive fusion fuel that is virtually nonexistent here on Earth. Because the moon lacks an atmosphere and has been bombarded by solar winds containing helium-3 for balloons of years, the moon has massive volumes of the isotope. Some estimates suggest there are at least 1.1 million metric tons of helium-3 on the lunar surface, enough to power human energy needs for up to 10,000 years." ftfyππππ
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Post by bodger on Oct 10, 2019 12:32:54 GMT
Anyway, wind turbines extract energy from the environment and that energy comes from a combination of the rotation of the earth, and the power of the sun. So some of the energy comes from slowing down the earthβs rotation. sounds like fairy dust to me. I don't buy it, and nor do most scientists.
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Post by Telemachus on Oct 10, 2019 14:41:02 GMT
Anyway, wind turbines extract energy from the environment and that energy comes from a combination of the rotation of the earth, and the power of the sun. So some of the energy comes from slowing down the earthβs rotation. sounds like fairy dust to me. I don't buy it, and nor do most scientists. So where does the energy come from then? Is it created out of nothing? (Probably not, if Mr Newton was right).
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Post by Mr Stabby on Oct 10, 2019 19:04:10 GMT
And there was me thinking that wind is generated by the effect of solar radiation heating up the surface of the Earth, and tides are formed by the combined gravitational effect of the sun and the moon. But solar eclipses are a sign of god's displeasure so don't mess with that shit. In other alternative energy news, how about the possibility of mining the moon for an isotope called helium-3? This is apparently why the Chinese are so keen to get there. Wind is in part generated by the effect of solar radiation heating up the surface of the earth. But if the earth always presented the same fact to the sun (ie rotated once a year) there would be no winds. Just a very hot side and a very cold side. It is only because the earth rotates faster than once a year, that we have winds and weather Which is what I said.
Not so, there would still be differences in atmospheric pressure and therefore there would still be wind. Fig. 7.26 On a non-rotating planet, heated air from the equator would rise and move toward the poles, cool, and sink. The cold air from the poles would then flow toward the equator completing the circulation.
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Post by Deleted on Oct 10, 2019 19:16:07 GMT
All this talk of planets reminds me of one of my favourite songs
(Do not watch if you are of a sensitive disposition). There is no swearing in it.
Early 80s so must admit this is not a new topic. Destruction of the human race by nature has been predicted for a long time.
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Post by Telemachus on Oct 10, 2019 19:22:05 GMT
Wind is in part generated by the effect of solar radiation heating up the surface of the earth. But if the earth always presented the same fact to the sun (ie rotated once a year) there would be no winds. Just a very hot side and a very cold side. It is only because the earth rotates faster than once a year, that we have winds and weather Which is what I said.
Not so, there would still be differences in atmospheric pressure and therefore there would still be wind. Fig. 7.26 On a non-rotating planet, heated air from the equator would rise and move toward the poles, cool, and sink. The cold air from the poles would then flow toward the equator completing the circulation. Yes I guess there would be circulation due to convection, but much, much less wind than we have now (unless you live in the doldrums)
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Post by bodger on Oct 10, 2019 20:06:26 GMT
sounds like fairy dust to me. I don't buy it, and nor do most scientists. So where does the energy come from then? Is it created out of nothing? (Probably not, if Mr Newton was right). it isn't important to ask where the energy comes from. it is important to understand that wind energy is absorbed by friction, mainly associated with contact with land structures; these could be mountains, high rise buildings, trees or wind turbines. it doesn't make any difference to the wind energy how it is absorbed - but it does make a difference to us if we can harness it instead of allowing it to be wasted in locations where it is of no benefit to us; harnessing it does not reduce the constant creation of new wind energy from sources like the sun's heat.
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