Naked Science Forum
On the Lighter Side => New Theories => Topic started by: Jolly- Joliver on 31/03/2011 16:27:17
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Basically this idea is to optimise solar panels.
So the solar panels would be placed in the center, and then on the outer side would be mirror or another substance to channel the light to the panels, thus giving the benefit of having a bigger pannel, and gaining the most light even in low light conditons.
Also to have the panels move into the best possible possition as plants do to catch the sun.
What do think? The panels move to an opitmal postion, using so form of device to locate the best position(that will have an energy expence) but also the panels have mirror petals like a flower to trap light an increase the overall size.
Any ideas about it?
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Or how about flying solar batteries.
A plane that has a giant battery which takes a day to charge, it flies by it's own power, follows the sun arround the earth, charging as it goes. lands each day leaving a fully charged battery and then takes off with a new empty battery.
Possible?
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Your plane would have to go very fast to keep up with the sun... and would take a lot of energy.
As far as solar concentrators and trackers. There are a number of different designs that are effective. Some solar cells such as the Boeing/Emcore triple junction cells work best with concentrated sunlight.
However, for ordinary solar panels, excess heat is a problem.
As far as your flower shape, you can also make a parabolic solar panel, somewhat like a large satellite dish. It will give you very concentrated heat in the middle, or at the focal point you choose.
I have a set of parabolic solar hot water panels (yet to install), but using a similar idea.
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Your plane would have to go very fast to keep up with the sun... and would take a lot of energy.
It would have to keep up with the turning of the earth.
If it takes off mid morning and get back mid evening the next day took off at 10am got back the next day at 5pm that would be 31 hours.
It could just fly arround the pole ofcourse.
As far as solar concentrators and trackers. There are a number of different designs that are effective. Some solar cells such as the Boeing/Emcore triple junction cells work best with concentrated sunlight.
However, for ordinary solar panels, excess heat is a problem.
We need to design better ones.
As far as your flower shape, you can also make a parabolic solar panel, somewhat like a large satellite dish. It will give you very concentrated heat in the middle, or at the focal point you choose.
I have a set of parabolic solar hot water panels (yet to install), but using a similar idea.
They are light concentrators, I've seen them, even met a guy last year who had developed an expresso maker, sun coffee, the concentrator heated the water. That just reflected sun light, I was thinking not so much in terms of concentration but just dricting more light to the panels, increasing what they get but not so much that they would over heat. It would also act to increase power when the sun light was low. More about making the panel think it was bigger than it actually was.
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Your plane would have to go very fast to keep up with the sun... and would take a lot of energy.
It would have to keep up with the turning of the earth.
If it takes off mid morning and get back mid evening the next day took off at 10am got back the next day at 5pm that would be 31 hours.
It could just fly arround the pole ofcourse.
I looked at travel times... London to JFK is about 8 hrs air-time, and 3 hrs "clock time".
11.5 hrs from London to LAX. Hmmm, only about 3.5 hrs "clock time".
Conventional planes are still energy inefficient.
Perhaps solar Zeppelins.
Hydrogen or Helium?
But you would likely be heavily dependent on Jetstreams which travel from West to East... But, then you would have a shortened day rather than a lengthened day.
I still think your benefits of such a program would be minimal unless your primary reason for the flights was transportation. For example, you might try a West to East around the world Zeppelin Mail Service.
Your benefits of high altitude solar panels would likely be restricted to getting above the cloud and smog levels. Otherwise it would be much better just to use terrestrial collectors.
You might be able to effectively use a tethered balloon. Or... you could likely be able to make a large solar kite. However, with that in mind, the question would be whether it is better to collect solar energy, or wind energy (or both) from your kite platform.
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There was a topic earlier about beaming power down from satellites which was effectively building a solar concentrator in space, and targeting it on a small area on the surface (perhaps also changing the spectrum).
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Perhaps the next "oil boom" in the Sahara will not be oil, but rather sunlight.
I could certainly envision large solar arrays to collect power for all the northern African cities, and perhaps even southern Spain.
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Your plane would have to go very fast to keep up with the sun... and would take a lot of energy.
It would have to keep up with the turning of the earth.
If it takes off mid morning and get back mid evening the next day took off at 10am got back the next day at 5pm that would be 31 hours.
It could just fly arround the pole ofcourse.
I looked at travel times... London to JFK is about 8 hrs air-time, and 3 hrs "clock time".
11.5 hrs from London to LAX. Hmmm, only about 3.5 hrs "clock time".
Conventional planes are still energy inefficient.
Perhaps solar Zeppelins.
Hydrogen or Helium?
Given the history I think most would perfer helium. Although Hydrogen gas from a zeppelin could also be used for hydrogen cars, old gases given over to another user, might have more market potencial.
But you would likely be heavily dependent on Jetstreams which travel from West to East... But, then you would have a shortened day rather than a lengthened day.
I still think your benefits of such a program would be minimal unless your primary reason for the flights was transportation. For example, you might try a West to East around the world Zeppelin Mail Service.
Perhaps both a mail service that charges giant batteries as it goes.
I was thinking before that you could transport cargo, using zeppelins, added advantage that you could drop where ever the customer wanted, no more road travel. less shipping cost, and direct delivery. If they charged batteries as they went, that would/could potentially get a lot of electricity, it's more carbon neutral, provides a more environmental service, and could provide a clean source of electricity.
There was a person I saw working on an idea for Africa, they have extremely bad roads so he wanted to use mini balloons or Zeppelins to ship in products safely.
Your benefits of high altitude solar panels would likely be restricted to getting above the cloud and smog levels. Otherwise it would be much better just to use terrestrial collectors.
You might be able to effectively use a tethered balloon. Or... you could likely be able to make a large solar kite. However, with that in mind, the question would be whether it is better to collect solar energy, or wind energy (or both) from your kite platform.
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There was a topic earlier about beaming power down from satellites which was effectively building a solar concentrator in space, and targeting it on a small area on the surface (perhaps also changing the spectrum).
Umm beaming electricity seems a bit dodgy.
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Perhaps the next "oil boom" in the Sahara will not be oil, but rather sunlight.
I could certainly envision large solar arrays to collect power for all the northern African cities, and perhaps even southern Spain.
If we used those area we could generate a lot of power, batteries could become a new form of super commodity, could be good business for an African nation. Charging giant batteries then selling them.
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I think you'd be better off with power lines than batteries.
Although, I could imagine converting a super-tanker to a giant battery. Push off from North Africa. Head across the sea to Southern France and plug it in. Your conversion efficiency would likely be less than 50%. So, the question would be whether it would be more or less efficient than using direct transmission lines.
Again, I think you'd be better off with your Zeppelin mail than batteries. For one thing, batteries are relatively heavy. Your net energy gains would be in displacing other transportation methods.
Hydrogen is about half the density if Helium, so it would have obvious benefits for creating lift, but obviously there are problems with flammability.
the LEL for H2 gas is about 4%. So, one should be pretty safe with using a 4% H2, 96% He mix. It wouldn't make a big difference, but it might have benefits. Perhaps one could even test higher percentages of H2.
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I think you'd be better off with power lines than batteries.
Although, I could imagine converting a super-tanker to a giant battery. Push off from North Africa. Head across the sea to Southern France and plug it in. Your conversion efficiency would likely be less than 50%.
It depends on the quantity doesnt it?
So, the question would be whether it would be more or less efficient than using direct transmission lines.
Again, I think you'd be better off with your Zeppelin mail than batteries.
The zepplin mail was your idea, combining them would give you both. I think zepplin cargo would be better tho.
For one thing, batteries are relatively heavy. Your net energy gains would be in displacing other transportation methods.
shipping and trucking, for zepplin, yet zepplin would be more enviromental, besides it wouldnt replace all of it, just have a place in the market, Shipping companies could run both, harldy compertician just an expanded service.
Hydrogen is about half the density if Helium, so it would have obvious benefits for creating lift, but obviously there are problems with flammability.
the LEL for H2 gas is about 4%. So, one should be pretty safe with using a 4% H2, 96% He mix. It wouldn't make a big difference, but it might have benefits. Perhaps one could even test higher percentages of H2.
A mixed gas might give you some of the benefits of both, a safer gas, but with hydrogens lift, you could also have an outer shell of helium arround a hydrogen core.
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Batteries are woefully heavy and inefficient, why on earth would you try to charge them not on earth?
Umm beaming electricity seems a bit dodgy.
He said power not electricity.
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Batteries are woefully heavy and inefficient, why on earth would you try to charge them not on earth?
That wasn't my suggestion
Umm beaming electricity seems a bit dodgy.
He said power not electricity.
The differnce between electrical power and electricity being what?
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Electricity is the movement of electrons, solar satellites would not beam electricty but microwaves.
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Electricity is the movement of electrons, solar satellites would not beam electricty but microwaves.
sorry I think electricity would be safer, whole microwaves?
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Electricity is the movement of electrons, solar satellites would not beam electricty but microwaves.
sorry I think electricity would be safer, whole microwaves?
I don't think I specified the wavelength.
Electricity is the movement of electrons.
Microwaves, X-Rays, UV, IR, and Visible light are all the movements of photons.
The only way to beam electricity is to create an artificial lightening bolt which would be extremely dangerous. And, it would be difficult to keep it going where one wanted it to go. Air resistance is also high, and there would be significant energy loss from the beam.
A laser (of your favorite spectrum) would have much less jumping and diffusion.
For space based solar collectors, one could either concentrate sunlight and beam the concentrated sunlight to earth (which would still be subject to cloud cover and other issues), or one could generate electricity, and then convert the electricity to microwaves, or something similar, and beam down the microwaves, and convert them back to electricity. The proposed energy levels are low enough that you could safely fly an airplane through the beam an not harm the passengers.
The implementation of such a system, however, would be extremely expensive.
If we are ever capable of building a carbon nanotube based space elevator. Graphite, Carbon Fiber, and Carbon Nanotubes are all excellent conductors. But, such a system is probably at least a century in the future, and to be effective for direct electricity conduction, one would have to design a + & - electrical pathway which might double the required effort to build it. Even so, a 36,000 km "wire" from a geosynchronous orbit would have significant resistance loss, and might be less efficient than the microwave energy conversion and transfer method.
I think that brings us back to the only practical place to implement solar panels for generating electricity to be used on earth is right here on earth.
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Electricity is the movement of electrons, solar satellites would not beam electricty but microwaves.
sorry I think electricity would be safer, whole microwaves?
I don't think I specified the wavelength.
I don't think he needs to, they're microwaves.
Electricity is the movement of electrons.
Microwaves, X-Rays, UV, IR, and Visible light are all the movements of photons.
The only way to beam electricity is to create an artificial lightening bolt which would be extremely dangerous. And, it would be difficult to keep it going where one wanted it to go. Air resistance is also high, and there would be significant energy loss from the beam.
A laser (of your favorite spectrum) would have much less jumping and diffusion.
For space based solar collectors, one could either concentrate sunlight and beam the concentrated sunlight to earth (which would still be subject to cloud cover and other issues)
With all the whole global warming issues wouldn't beaming sunlight, just increase the temp of the atmosphere as it travelled through?
, or one could generate electricity, and then convert the electricity to microwaves, or something similar, and beam down the microwaves, and convert them back to electricity. The proposed energy levels are low enough that you could safely fly an airplane through the beam an not harm the passengers.
Are you sure? A beam of microwaves wouldn't hurt the passengers? or damage the plane? We do use them to cook food dont forget.
The implementation of such a system, however, would be extremely expensive.
If we are ever capable of building a carbon nanotube based space elevator. Graphite, Carbon Fiber, and Carbon Nanotubes are all excellent conductors. But, such a system is probably at least a century in the future, and to be effective for direct electricity conduction, one would have to design a + & - electrical pathway which might double the required effort to build it. Even so, a 36,000 km "wire" from a geosynchronous orbit would have significant resistance loss, and might be less efficient than the microwave energy conversion and transfer method.
But you could use it to transmit electricity, if it was conductive. Besides this whole microwave idea sounds too dodgy to me.
But then again I am not sure a cable from space could really work either, thinking about hurricans etc, you could place it somewhere more stable, near the poles maybe, and construct a small edifice arround the base, to protect it from some of the enviromental problems involved.
I think that brings us back to the only practical place to implement solar panels for generating electricity to be used on earth is right here on earth.
I didn't think it would be ecconomical to put solar panel in space anyway, they are great for the satalites and other things in space, but as a means to get electrical power, we can get access to sun light from the ground, or in the atmosphere.
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Going back to the main question.
If we did make a flower shaped solar panel light concentrator. About the size of a sun flower, say 10" inch circular solar panel, then petals that helped to concentrate extra light to the solar panel, with a system to move the flower to the position with most available light.
What do you think an average day would produce in terms of electricity? It would work from sun rise to sun set.
And for a cloudless summers day?
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Solar concentrators are only used because mirrors and lenses may be cheaper to make than the individual solar cells. And, as mentioned, some solar cells such as the Boeing/Emcore triple junction cells have increased efficiency with concentrated light.
But... in general, a 1 m2 concentrator would not generate any more power than a 1 m2 solar panel.
The conversion efficiency of your typical silicone based solar cell is about 10-20%.
The conversion efficiency of the triple junction cells with concentrated light is as high as 41%.
Most solar panels are sold with a watt rating. Large panels are often in the 100W to 200W range.
My earlier experiments indicated that that was a little high of a rating, but I had old panels set at a fixed angle. I was also getting about 10% or less of the normal power on cloudy days. I have some better tests planned, but not implemented yet.
Anyway, with a little luck, with a 200W solar panel, you might get 200 Watt-hrs on a sunny day, and 20 Watt-hrs on a cloudy day.
This website has some good forums for alternative energy:
http://www.fieldlines.com
They will chew you up if you don't formulate your question well. They may have some links to resources to find the average daily solar energy at different latitudes, from which you should be able to calculate the daily power generated based on the conversion efficiency of your panels.
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Solar concentrators are only used because mirrors and lenses may be cheaper to make than the individual solar cells. And, as mentioned, some solar cells such as the Boeing/Emcore triple junction cells have increased efficiency with concentrated light.
But... in general, a 1 m2 concentrator would not generate any more power than a 1 m2 solar panel.
The conversion efficiency of your typical silicone based solar cell is about 10-20%.
The conversion efficiency of the triple junction cells with concentrated light is as high as 41%.
Most solar panels are sold with a watt rating. Large panels are often in the 100W to 200W range.
My earlier experiments indicated that that was a little high of a rating, but I had old panels set at a fixed angle. I was also getting about 10% or less of the normal power on cloudy days. I have some better tests planned, but not implemented yet.
It was for cloudy days I was thinking that having something to concentrate more light to the panel would help increase the energy, moving it in line with the light would help also.
What do you think about this idea- rather than spending lots on a system to asses the best position and move the panel to it by computer program, You simply look at the suns postion as it travels across the sky, then every 30mins the panel moves to the place it knows the sun will be?
Rather then spending lots on a system to find the best place and move to it, the panels has set programed movments for location on earth and time. So will just move once or twice an hour and simply move to a position more or less where the sun will be as it travels across the sky. Combining that with some extra reflectors should give a far greater amount of energy esp on a cloudy day.
Anyway, with a little luck, with a 200W solar panel, you might get 200 Watt-hrs on a sunny day, and 20 Watt-hrs on a cloudy day.
This website has some good forums for alternative energy:
http://www.fieldlines.com
Thanks I'll check it out
They will chew you up if you don't formulate your question well. They may have some links to resources to find the average daily solar energy at different latitudes, from which you should be able to calculate the daily power generated based on the conversion efficiency of your panels.
There not my panels, I'm unlikely to build one, this was just an idea, and I thought a good place for discussion and suggestions relating to it. As best I can work out at the moment the panels need to be a bit better to be able to except more concentrated light on them, so I think if anyone actually looked into the added light concentration, it's goning to have to start with how much could they except, then working out a way to reduce petals should there be too much light on the panels.
But I think the idea for adding reflectors and a programe to move the panel more or less in line with the sun should certainly give something of a better energy yeald, esp on the bad light days.
And actually thinking about it, it's the bad light days and ways of increasing the outputs, that are the main areas that we need to work on improving(with the panel technology also), Good light days should always be fine.
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Hopefully I'll get some panels deployed again this year, and likely with a tracker.
I think the tracking electronics are relatively simple. But, I have also wondered if it would be better to just program in where the sun will be. Then perhaps rotate 1 degree every 4 minutes (or so).
The power efficiency lost by not tracking the sun is much greater than merely using geometry to calculate the area exposed to the sun.
A concentrated system, however, must have fairly accurate solar tracking, otherwise it is ineffective.
On a cloudy day, you have two effects. Obviously you get less sunlight. But, you also get a diffuse nature of the sunlight. Generally slightly more in the direction of the sun, but overall diffuse across the sky. It is much more difficult to design a concentrator for a diffuse light source than a point-source.
I'm not sure if it is best to track the sun, or shut down the tracker on a cloudy day (unless the sun periodically pokes through the clouds). For some time now, I've been planning on doing some tests with the Sanyo Bifacial panels on cloudy days.
http://us.sanyo.com/HIT-Power-Double/HIT-Double-Bifacial-Photovoltaic-Module
My idea is that while the gain from the back side is minimal on a sunny day, the gain is proportionally more on a cloudy day. However, the point might be that double nothing is still nothing. At this point, the Sanyo panels seem to be more expensive than other brands, and thus it might be better to just buy larger single-sided panels.
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Hopefully I'll get some panels deployed again this year, and likely with a tracker.
I think the tracking electronics are relatively simple. But, I have also wondered if it would be better to just program in where the sun will be. Then perhaps rotate 1 degree every 4 minutes (or so).
Thinking about it a programmed movement will save energy, it will just move into a fixed position relative to where the sun will be. Whereas a system that moves with the light could possibly move all the time.
The power efficiency lost by not tracking the sun is much greater than merely using geometry to calculate the area exposed to the sun.
A concentrated system, however, must have fairly accurate solar tracking, otherwise it is ineffective.
On a cloudy day, you have two effects. Obviously you get less sunlight. But, you also get a diffuse nature of the sunlight. Generally slightly more in the direction of the sun, but overall diffuse across the sky. It is much more difficult to design a concentrator for a diffuse light source than a point-source.
but any concentrator should increase the amount of light that the panel receives.
I'm not sure if it is best to track the sun, or shut down the tracker on a cloudy day (unless the sun periodically pokes through the clouds). For some time now, I've been planning on doing some tests with the Sanyo Bifacial panels on cloudy days.
http://us.sanyo.com/HIT-Power-Double/HIT-Double-Bifacial-Photovoltaic-Module
My idea is that while the gain from the back side is minimal on a sunny day, the gain is proportionally more on a cloudy day. However, the point might be that double nothing is still nothing. At this point, the Sanyo panels seem to be more expensive than other brands, and thus it might be better to just buy larger single-sided panels.
I'm not sure about the different panels but I think, believe that on a cloud day with something to attract more light to the panel, and something to move the panel into a postion directly below the suns position should give you something.
But that is why we experiment to find out. Just looking at the ambient light reception on the underside of the panel you could also set up a concentrator for that as well.
or how about flipping the panel arround and moving the concentrators downward to concentrate light on the underneath, and so leaving the ambient part more open?
Good luck with the trials
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Wow a solar flower, did your idea come from the concept of Biomimetics? If so then you should consider that the purpose of the flower is not to increase photosynthesis but solely for reproduction, the flower normally being an advertisement for insects to propagate pollination. Of course there are always exceptions like carnivorous plants for example.
Any system that uses a tracking device to follow the sun through the day would also consume a bit of the energy you are trying to collect although I suspect that the overall result would be better instead of having the panels fixed.