dlkf writes: "There is an article on Space.com that talks about some of the benefits, costs and current research relevant to using satellites to generate and store power. This surplus of power could then be beamed via laser or microwave to earth or other satellites."
Japan seems to think it's worthwhile...
by
tomknight
·
· Score: 2, Informative
...after all, why else would they be planning on having one in the pretty near future?. This is interesting becasue Japan's not really afraid (it seems) to use nuclear power, and the satellite power is considerebly more expensive per kilowatt hour.
Tom.
-- Oh arse
Re:Radiations would kill us all
by
Faulder
·
· Score: 3, Informative
The wavelength (frequency) of the microwaves is what makes it excite water. I'm sure they would not be using the same wavelength to transmit energy from space to earth. Clouds and water vapor in the air would affect it.
Re:Bad Idea... Perhaps not
by
conan_albrecht
·
· Score: 5, Informative
I recently discussed this idea with a planetary scientist. We did a little research and here's what we came up with:
The microwave beam does not disrupt any planes, etc. because they are made of metal. Even a small amount of metal shields microwaves in the frequency that would be used -- same reason that metal won't heat in your home microwave -- it just reflects the light waves.
Organic beings that come into the focused beam cone are not affected much by the beam. Microwave s only sink into your skin about 1-2 inches. At most it raises your body temperature one or two degrees. Of course, people won't normally be inside of these beam cones anyway.
Earth-based solar stations have to put up with night. Orbital solar arrays only have a few hours of blackout each year. Most of the year they can beam the microwave down 24 hours per day, even in geosynchronous orbit over a country like Japan.
It may not be the best alternative for countries such as the U.S., but it makes more sense for smaller countries such as Japan that have almost no natural energy resources.
My $0.02.
Re:Radiations would kill us all
by
Anonymous Coward
·
· Score: 1, Informative
More pedantically, the microwave frequency matches the resonant frequncy of the hydrogen-oxygen bond and the microwave energy exites these bonds, causing them to vibrate. These vibrations are realeased (during molecular collisions) as greater molecular speed - i.e. heat.
Also, to those who fear microwaves from on high, have you ever been out on a sunny day? Have you felt the warmth? Guess what... What we call "microwave" and what we call "infra-red" - radiant heat - actually have a considerable overlap. Better get used to the idea, it's already happening!
Anonymous Colin, who can't remember/fetch his password here.
Problems with solar power
by
wiredog
·
· Score: 5, Informative
OK, several posters have said "Why not just use solar cells?". Here's why:
Solar power is not quite ready yet. If you live in an area, such as the desert southwest of the USA, that gets lots of sun, then solar can work. The initial cost is higher than other power sources, but people do it. The maintenance factor is a problem as well, since most solar power systems require batteries for storage. My previous employer looked at solar quite seriously because the line power, in Cedar City Utah, sucked. Brownouts were common. It turned out to be cheaper to replace equipment on a yearly basis than to put solar cells and a battery bank in.
If you live in an area such as the northwest of the USA then you can forget about solar. There are too many cloudy days.
Putting a bank of solar cells in the Nevada desert would work for Nevada, but distributing it beyond Nevada would be difficult.
The cloudy days and the distribution problems apply to SPS as well. The price of solar is going down, and in the desert areas it will probably be a better solution than SPS. In a few years.
Re:Problems with solar power
by
TonyJohn
·
· Score: 2, Informative
Even on a cloudy day, the earth receives a load of power from the sun. (In strong sunlight about 1kW/square metre, in cloud at high latitudes it can go down to 300W/m.m). It is possible if you cover your roof with solar tiles to generate (on average) the same amount of power as you consume. With the current low-cost of electricity (which does not take into account the cost of the carbon emissions), the economics are poor though.
You don't have to have batteries - you can remain connected to the grid, and sell or buy electricity as needed. Not good if you are trying to survive a brownout though.
-- Owl tried to think of something wise to say, but couldn't.
Re:Why bother when there are better alternatives!
by
shaunak
·
· Score: 2, Informative
"For a tenth of the cost we can cover several square miles of the nevada desert with solar arrays. This will produce ten times the power without the problems of beaming the power back to the ground."
Do you have any solid 'figures' to back this claim up?
When it comes to the photo electric effect, E = hv
Now, when it comes to E, as v increases, E increases.
Here on the earth, we do not recieve most high frequency radiation (think Ultra Violet, think Cosmic) which is available in abundence in Space.
Consider that thought for a moment.
-- -Shaunak.
O'Niell O'Shmeal
by
Iron+Sun
·
· Score: 2, Informative
Sorry, but I think you've been buying into a bit too much hype.
This was first seriously proposed by Gerald K. Oneill of Princeton University in 1975! It was feasable ( and even profitable ) then
No, it wasn't even remotely profitable in the 70s, just as it is not (quite) profitable now. When O'Neill made his calculations in the mid-70s, he projected several future technologies that would make his schemes affordable, the foremost being cheap, reliable, regular access to space. In 1975, the space shuttle was 7 years away from its maiden flight, and everybody believed the bullshit about the fleet flying one mission per week with perfect safety. This has not proven to be the case.
Until we get a 10-fold reduction in launch costs, and launches are handled more like airport departures, then schemes such as this will remain prohibitively expensive. I want it as much as the next geek, but I'd rather focus on what concrete steps we can take in the next 5-10 years. Cheap access is the breakthough tech.
Does anyone question that this would be a better place to be... and we could be there by now, if only we had the vision, and the will.
Of course it would be a better place to be. World peace would be nice too, but we're going to need a bit more than abstract notions of vision and will to get us there.
This whole line about 'lack of will' is one that I see quite frequently on/. from starry-eyed, impatient idealists who want to holiday on the Moon RIGHT NOW. If you try to explain about economics, technological development, or engineering project turnaround times, they frequently have problems accepting this. Not wanting to believe that they may have to wait a while to get all Buck Rogers, they cast about for the real reason, and latch on 'political will'. It was politicians that cut short the Apollo program, so it's politicians fault that there isn't currently a lunar Hilton.
Umm, no. Lack of funding (as well as bureaucratic inefficiency) may be retarding the rate of advance, but we can't blame Washington because we don't have a warp drive yet. Let's take things one step at a time. As soon as such projects become economically feasible, you can bet your bottom dollar someone will come forward with a business plan.
WHY THIS GOT MODDED AS TROLL
by
Medievalist
·
· Score: 2, Informative
Somebody obviously ripped this off from some other site, without attribution. That's not really a problem on/., where plagarism is seen by some as a god-granted right;^), but then the copier edited the text near the end to insert a bunch of racist nonsense.
It looks like the bigot is hoping you'll clip it and copy it yourself and spread his or her lunacy under your own name. The text chosen is long and appears mostly correct to lull you into the trap.
This stuff is becoming more common on/., and it's really sad that some morons have nothing better to do with their time. Good job Mr. Moderator, thanks for reading it all the way through.
--Charlie
Re:Radiations would kill us all
by
Telek
·
· Score: 4, Informative
2.45GHz and 10GHz would be common wavelengths based on past studies. Your microwave operates at... oh 2.5GHz!
But fear not! There's more to the microwave science than meets the eye.
You see, in order for microwaves to do anything, they have to be absorbed into something and not re-emitted
This only happens when you have something in a liquid state... Otherwise, for example, when microwaves pass through steam they will excite the water molucules by causing them to vibrate madly, but as soon as the microwaves have finished passing through them the molecules stop vibrating, and nothing changes. The only way that you will get it to heat up a lot is if, in the process of causing those molecules to vibrate, those molecules rub against other molecules and transfer some kinetic energy. This can only happen effectively in liquid states.
If it's in a gaseous state and you have a constant beam that will continue to excite the water molecules in it's path, but due to winds and the fact that once you heat up a gas it will expand and move around on it's own you won't have a very large problem. If it's raining or you have a very dense cloud that's about to cause a storm, then you might have a problem, but under normal circumstances you'd be fine.
I remember reading somewhere that a good analogy was to think of them like this: imagine an object floating on water as waves pass by. The object will bob up and down but once the waves have passed there is no appreciable net change in energy to the object. However now imagine that this object was sitting right next to a fixed object, like a boat and a dock. As the boat bobs up and down it will rub up against the dock and friction will cause the dock to warm up. Same deal here.
--
If God gave us curiosity
Re:sorry...but..
by
Anonymous Coward
·
· Score: 1, Informative
Because truely efficient solar generation plants on earth will require lots of land...defeinitely more than we can spare, and at best they'll run less then 16 hours a day.
In space, depending on how you orient the station, you could get almost continuous, maximum light on your cells, with no atmosphere to dilute the sun's rays.
If we can create solar cells that can last for quite some time ( or a space-based solar cell re-manufacturing process thats easily automated and requires few raw materials...maybe not ), we might be able to offset the cost of lifting those materials in the first place.
Re:Why not use the acres of urban tarpaper?
by
markmoss
·
· Score: 3, Informative
If we _are_ going to solar power collected on Earth, then covering rooftops is definitely the way to go. It's been a long time since I did the calculations, but the way I figured it (1) we'd need less than 50% of the total roof area in the US, and (2) blocking the sun from that much undeveloped land would be a massive ecological disaster... (There is life even in the Nevada desert.)
But it's very expensive. Solar cells cost over $1/watt the last time I looked. And 1KW of solar cells gives you far less than 1KW of delivered power most of the time -- they are rated for peak power, which is aimed directly at the sun at noon on a clear day on a mountaintop in the tropics. I did some datalogging with a small solar panel where I live this summer; in a Michigan summer, clear days give you the equivalent of 2 hrs/day at full power. Many days aren't clear, some are so cloudy that I never got enough current to measure. Overage, I think a 1KW panel around here will collect 1KW-hour per day in the summer. Winter is going to be a lot worse. I'm also testing a small windcharger -- it didn't collect enough energy to notice in September, October is shaping up a little better, and maybe it will give a decent power output when the winter storms start hitting...
California would be better, and Tucson AZ might get 5KW-hour/day. Most American homes use considerably more than that, so you need several KW of collector. Then you also have to store the energy for night-time use. In a house-sized system, that storage is batteries, so you also need a batter charger and inverter to convert from and to AC. I'm told that the overall cost of a solar power system (panels, batteries, electronics, and wiring) for one house is $20K to $60K, and that is if you cut your power usage well below average and use either a back-up generator or a connection to the power grid for prolonged storms. (In northern Michigan, we'd probably be on back-up power Oct-March, unless another $20K into windchargers would give us winter power.) Or you can pay the power company about $100/month. It only makes sense if (1) you are an eco-freak, or (2) your house is so far back in the woods you have to pay $10K or more to get a power line hooked up. But then you also have to buy the massive inverter needed to power a well. (You can't run a 4 inch submerged pump from 24 or 48VDC -- the wiring needed would be too thick. You need 240V to bring the current down.)
If you are putting solar panels on city/suburban rooftops and connecting them to the grid, then the costs are probably lower. Each place needs an inverter that will sync to AC already on the lines -- in mass production that's not much more expensive than the inverter needed for stand-alone operation. There has to be one big energy storage system, but on a large scale there are cheaper options than batteries. For instance two ponds, one on top of a hill, one at the bottom. Pump water to the top in the daytime, and let it flow back through a turbine at night. Or convert excess electricity to hydrogen, and store it or pipe it to someplace less blessed with sunlight, then burn it in gas turbines, fuel cells, or even a converted coal plant.
But notice that in any of these cases, the final stage is still as costly to build as a conventional (fossil-fuel or hydro) electric system, plus someone has to pay for all those solar collectors, and inverters. The economics isn't there until either fuel gets more expensive or solar cells get much cheaper.
So how is a solar power satellite going to beat this? It will stay at peak power 24 hours a day, so you get 6-12 times as much energy as from the same solar panel in L.A. and reduce the requirement for night-time storage and backup power, but that's not nearly enough to make up for the launch costs.
However, an SPS does not have to use expensive semiconductors for energy conversion. Use a big mirror (e.g. a balloon with one half clear, the other half aluminized) to focus the sun on a boiler. The mirror stays pointed just by pointing the power plant at the sun and then spinning it around the mirror axis. (Pointing the microwave antenna at a fixed spot on Earth could be a problem -- maybe use phased arrays?) The only heavy parts of this system are the boiler, turbine, and condenser. Big steam plants get well over 30% efficiency, and this is better than any solar cell I have heard of. You could do this on earth too, but you've got to turn that big mirror to follow the sun, brace it against winds, etc., so it's pretty costly, although at this time it would be definitely cheaper than launching a much lighter SPS into space...
What would really make it economical would be to mine the materials and build the SPS in space. And the enthusiast's real goal is to get that mfg capacity up there -- because then they could build pretty much anything needed to colonize space. And if some earth-based gov't thinks they have to pay taxes...oops, lost control of that beam for a few minutes, sorry.
Space solar power will happen
by
wronkiew
·
· Score: 2, Informative
As nuclear and fossil fuels become harder to find, beaming solar power from space will become feasible. When that happens, the companies and governments which have developed the necessary technologies will reap the rewards. An analysis of NASA's attempts to do so can be found at http://www.nap.edu/books/0309075971/html/. This is the document mentioned in the Space.com article. Check out The SSP Monitor for more space solar power information
Re:Why not use the acres of urban tarpaper?
by
markmoss
·
· Score: 3, Informative
Actually, the best orbit for beaming to one spot on the ground is not just geosynchronous but geostationary: above the equator & 24 hour period. Because the Earth's axis is tilted, the orbit is at 40,000 miles radius, and Earth is only 8,000 miles in diameter, the satellite rarely passes into the Earth's shadow. At the equinoxes, it will be shadowed when it goes around the far side of the Earth, but that's only a couple of hours a day or less for a few days. So for that couple of hours (which would probably be around midnight), you have to draw power from some other satellite in a slightly different orbit, turn on your hydrogen-burning back-up power turbines, or simply declare a "blackout holiday". The rest of the year, the satellite is "above" or "below" the poles while transiting the far side.
Re:Space Solar Power: A Fresh Look
by
Antaeus+Feldspar
·
· Score: 3, Informative
Where the worthwhile portion of the parent comment was plagiarized from.
-- If people are to respect the law, perhaps the law should begin by respecting the people.
Slashdot Mirror
Tom.
Oh arse
The wavelength (frequency) of the microwaves is what makes it excite water. I'm sure they would not be using the same wavelength to transmit energy from space to earth. Clouds and water vapor in the air would affect it.
- The microwave beam does not disrupt any planes, etc. because they are made of metal. Even a small amount of metal shields microwaves in the frequency that would be used -- same reason that metal won't heat in your home microwave -- it just reflects the light waves.
- Organic beings that come into the focused beam cone are not affected much by the beam. Microwave s only sink into your skin about 1-2 inches. At most it raises your body temperature one or two degrees. Of course, people won't normally be inside of these beam cones anyway.
- Earth-based solar stations have to put up with night. Orbital solar arrays only have a few hours of blackout each year. Most of the year they can beam the microwave down 24 hours per day, even in geosynchronous orbit over a country like Japan.
It may not be the best alternative for countries such as the U.S., but it makes more sense for smaller countries such as Japan that have almost no natural energy resources.My $0.02.
More pedantically, the microwave frequency matches the resonant frequncy of the hydrogen-oxygen bond and the microwave energy exites these bonds, causing them to vibrate. These vibrations are realeased (during molecular collisions) as greater molecular speed - i.e. heat.
Also, to those who fear microwaves from on high, have you ever been out on a sunny day? Have you felt the warmth? Guess what... What we call "microwave" and what we call "infra-red" - radiant heat - actually have a considerable overlap. Better get used to the idea, it's already happening!
Anonymous Colin, who can't remember/fetch his password here.
Solar power is not quite ready yet. If you live in an area, such as the desert southwest of the USA, that gets lots of sun, then solar can work. The initial cost is higher than other power sources, but people do it. The maintenance factor is a problem as well, since most solar power systems require batteries for storage. My previous employer looked at solar quite seriously because the line power, in Cedar City Utah, sucked. Brownouts were common. It turned out to be cheaper to replace equipment on a yearly basis than to put solar cells and a battery bank in.
If you live in an area such as the northwest of the USA then you can forget about solar. There are too many cloudy days.
Putting a bank of solar cells in the Nevada desert would work for Nevada, but distributing it beyond Nevada would be difficult.
The cloudy days and the distribution problems apply to SPS as well. The price of solar is going down, and in the desert areas it will probably be a better solution than SPS. In a few years.
Best Slashdot Co
"For a tenth of the cost we can cover several square miles of the nevada desert with solar arrays. This will produce ten times the power without the problems of beaming the power back to the ground."
Do you have any solid 'figures' to back this claim up?
When it comes to the photo electric effect, E = hv
Now, when it comes to E, as v increases, E increases.
Here on the earth, we do not recieve most high frequency radiation (think Ultra Violet, think Cosmic) which is available in abundence in Space.
Consider that thought for a moment.
-Shaunak.
Sorry, but I think you've been buying into a bit too much hype.
This was first seriously proposed by Gerald K. Oneill of Princeton University in 1975! It was feasable ( and even profitable ) then
No, it wasn't even remotely profitable in the 70s, just as it is not (quite) profitable now. When O'Neill made his calculations in the mid-70s, he projected several future technologies that would make his schemes affordable, the foremost being cheap, reliable, regular access to space. In 1975, the space shuttle was 7 years away from its maiden flight, and everybody believed the bullshit about the fleet flying one mission per week with perfect safety. This has not proven to be the case.
Until we get a 10-fold reduction in launch costs, and launches are handled more like airport departures, then schemes such as this will remain prohibitively expensive. I want it as much as the next geek, but I'd rather focus on what concrete steps we can take in the next 5-10 years. Cheap access is the breakthough tech.
Of course it would be a better place to be. World peace would be nice too, but we're going to need a bit more than abstract notions of vision and will to get us there.
This whole line about 'lack of will' is one that I see quite frequently on /. from starry-eyed, impatient idealists who want to holiday on the Moon RIGHT NOW. If you try to explain about economics, technological development, or engineering project turnaround times, they frequently have problems accepting this. Not wanting to believe that they may have to wait a while to get all Buck Rogers, they cast about for the real reason, and latch on 'political will'. It was politicians that cut short the Apollo program, so it's politicians fault that there isn't currently a lunar Hilton.
Umm, no. Lack of funding (as well as bureaucratic inefficiency) may be retarding the rate of advance, but we can't blame Washington because we don't have a warp drive yet. Let's take things one step at a time. As soon as such projects become economically feasible, you can bet your bottom dollar someone will come forward with a business plan.
It looks like the bigot is hoping you'll clip it and copy it yourself and spread his or her lunacy under your own name. The text chosen is long and appears mostly correct to lull you into the trap.
This stuff is becoming more common on /., and it's really sad that some morons have nothing better to do with their time. Good job Mr. Moderator, thanks for reading it all the way through.
--Charlie
2.45GHz and 10GHz would be common wavelengths based on past studies. Your microwave operates at ... oh 2.5GHz!
But fear not! There's more to the microwave science than meets the eye.
You see, in order for microwaves to do anything, they have to be absorbed into something and not re-emitted
This only happens when you have something in a liquid state... Otherwise, for example, when microwaves pass through steam they will excite the water molucules by causing them to vibrate madly, but as soon as the microwaves have finished passing through them the molecules stop vibrating, and nothing changes. The only way that you will get it to heat up a lot is if, in the process of causing those molecules to vibrate, those molecules rub against other molecules and transfer some kinetic energy. This can only happen effectively in liquid states.
If it's in a gaseous state and you have a constant beam that will continue to excite the water molecules in it's path, but due to winds and the fact that once you heat up a gas it will expand and move around on it's own you won't have a very large problem. If it's raining or you have a very dense cloud that's about to cause a storm, then you might have a problem, but under normal circumstances you'd be fine.
I remember reading somewhere that a good analogy was to think of them like this: imagine an object floating on water as waves pass by. The object will bob up and down but once the waves have passed there is no appreciable net change in energy to the object. However now imagine that this object was sitting right next to a fixed object, like a boat and a dock. As the boat bobs up and down it will rub up against the dock and friction will cause the dock to warm up. Same deal here.
If God gave us curiosity
Because truely efficient solar generation plants on earth will require lots of land...defeinitely more than we can spare, and at best they'll run less then 16 hours a day.
In space, depending on how you orient the station, you could get almost continuous, maximum light on your cells, with no atmosphere to dilute the sun's rays.
If we can create solar cells that can last for quite some time ( or a space-based solar cell re-manufacturing process thats easily automated and requires few raw materials...maybe not ), we might be able to offset the cost of lifting those materials in the first place.
If we _are_ going to solar power collected on Earth, then covering rooftops is definitely the way to go. It's been a long time since I did the calculations, but the way I figured it (1) we'd need less than 50% of the total roof area in the US, and (2) blocking the sun from that much undeveloped land would be a massive ecological disaster... (There is life even in the Nevada desert.)
But it's very expensive. Solar cells cost over $1/watt the last time I looked. And 1KW of solar cells gives you far less than 1KW of delivered power most of the time -- they are rated for peak power, which is aimed directly at the sun at noon on a clear day on a mountaintop in the tropics. I did some datalogging with a small solar panel where I live this summer; in a Michigan summer, clear days give you the equivalent of 2 hrs/day at full power. Many days aren't clear, some are so cloudy that I never got enough current to measure. Overage, I think a 1KW panel around here will collect 1KW-hour per day in the summer. Winter is going to be a lot worse. I'm also testing a small windcharger -- it didn't collect enough energy to notice in September, October is shaping up a little better, and maybe it will give a decent power output when the winter storms start hitting...
California would be better, and Tucson AZ might get 5KW-hour/day. Most American homes use considerably more than that, so you need several KW of collector. Then you also have to store the energy for night-time use. In a house-sized system, that storage is batteries, so you also need a batter charger and inverter to convert from and to AC. I'm told that the overall cost of a solar power system (panels, batteries, electronics, and wiring) for one house is $20K to $60K, and that is if you cut your power usage well below average and use either a back-up generator or a connection to the power grid for prolonged storms. (In northern Michigan, we'd probably be on back-up power Oct-March, unless another $20K into windchargers would give us winter power.) Or you can pay the power company about $100/month. It only makes sense if (1) you are an eco-freak, or (2) your house is so far back in the woods you have to pay $10K or more to get a power line hooked up. But then you also have to buy the massive inverter needed to power a well. (You can't run a 4 inch submerged pump from 24 or 48VDC -- the wiring needed would be too thick. You need 240V to bring the current down.)
If you are putting solar panels on city/suburban rooftops and connecting them to the grid, then the costs are probably lower. Each place needs an inverter that will sync to AC already on the lines -- in mass production that's not much more expensive than the inverter needed for stand-alone operation. There has to be one big energy storage system, but on a large scale there are cheaper options than batteries. For instance two ponds, one on top of a hill, one at the bottom. Pump water to the top in the daytime, and let it flow back through a turbine at night. Or convert excess electricity to hydrogen, and store it or pipe it to someplace less blessed with sunlight, then burn it in gas turbines, fuel cells, or even a converted coal plant.
But notice that in any of these cases, the final stage is still as costly to build as a conventional (fossil-fuel or hydro) electric system, plus someone has to pay for all those solar collectors, and inverters. The economics isn't there until either fuel gets more expensive or solar cells get much cheaper.
So how is a solar power satellite going to beat this? It will stay at peak power 24 hours a day, so you get 6-12 times as much energy as from the same solar panel in L.A. and reduce the requirement for night-time storage and backup power, but that's not nearly enough to make up for the launch costs.
However, an SPS does not have to use expensive semiconductors for energy conversion. Use a big mirror (e.g. a balloon with one half clear, the other half aluminized) to focus the sun on a boiler. The mirror stays pointed just by pointing the power plant at the sun and then spinning it around the mirror axis. (Pointing the microwave antenna at a fixed spot on Earth could be a problem -- maybe use phased arrays?) The only heavy parts of this system are the boiler, turbine, and condenser. Big steam plants get well over 30% efficiency, and this is better than any solar cell I have heard of. You could do this on earth too, but you've got to turn that big mirror to follow the sun, brace it against winds, etc., so it's pretty costly, although at this time it would be definitely cheaper than launching a much lighter SPS into space...
What would really make it economical would be to mine the materials and build the SPS in space. And the enthusiast's real goal is to get that mfg capacity up there -- because then they could build pretty much anything needed to colonize space. And if some earth-based gov't thinks they have to pay taxes...oops, lost control of that beam for a few minutes, sorry.
As nuclear and fossil fuels become harder to find, beaming solar power from space will become feasible. When that happens, the companies and governments which have developed the necessary technologies will reap the rewards. An analysis of NASA's attempts to do so can be found at http://www.nap.edu/books/0309075971/html/. This is the document mentioned in the Space.com article. Check out The SSP Monitor for more space solar power information
Actually, the best orbit for beaming to one spot on the ground is not just geosynchronous but geostationary: above the equator & 24 hour period. Because the Earth's axis is tilted, the orbit is at 40,000 miles radius, and Earth is only 8,000 miles in diameter, the satellite rarely passes into the Earth's shadow. At the equinoxes, it will be shadowed when it goes around the far side of the Earth, but that's only a couple of hours a day or less for a few days. So for that couple of hours (which would probably be around midnight), you have to draw power from some other satellite in a slightly different orbit, turn on your hydrogen-burning back-up power turbines, or simply declare a "blackout holiday". The rest of the year, the satellite is "above" or "below" the poles while transiting the far side.
Where the worthwhile portion of the parent comment was plagiarized from.
If people are to respect the law, perhaps the law should begin by respecting the people.