Has there ever been an airliner design involving reducing generator load by installing solar panels?Would “wind turbine generators” in the bypass stream save fuel for jetliners?Is solar power used (as auxiliary power) on commercial aircraft?What are the advantages of the B747-8 airfoil over B737's airfoil?Have other designs for individual gasper ventilation been tried?Why hasn't there ever been a large 4-engine commercial airplane with 2 engines on the wings and 2 engines at the tail?Feasibility of using secondary props to generate power on an electric model aircraftCould there ever be a fully solar powered airliner capable of transatlantic flights?Would “wind turbine generators” in the bypass stream save fuel for jetliners?Has there ever been a seaplane with inflatable airbags rather than traditional pontoons?Would it have been feasible to install 'conformal fuel tanks' on the Mercure?What is the feasibility of solar powered drones?Why did narrowbody jetliners take so long to switch over to high-bypass engines?
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Has there ever been an airliner design involving reducing generator load by installing solar panels?
Would “wind turbine generators” in the bypass stream save fuel for jetliners?Is solar power used (as auxiliary power) on commercial aircraft?What are the advantages of the B747-8 airfoil over B737's airfoil?Have other designs for individual gasper ventilation been tried?Why hasn't there ever been a large 4-engine commercial airplane with 2 engines on the wings and 2 engines at the tail?Feasibility of using secondary props to generate power on an electric model aircraftCould there ever be a fully solar powered airliner capable of transatlantic flights?Would “wind turbine generators” in the bypass stream save fuel for jetliners?Has there ever been a seaplane with inflatable airbags rather than traditional pontoons?Would it have been feasible to install 'conformal fuel tanks' on the Mercure?What is the feasibility of solar powered drones?Why did narrowbody jetliners take so long to switch over to high-bypass engines?
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Has there ever been a trial/project/design, in which solar panels were incorporated in the design of a commerical airliner (e.g. on the wings), with the aim to reduce fuel consumption by lowering the generator workload?
If no, why not?
aircraft-design electrical-system solar-power
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show 8 more comments
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Has there ever been a trial/project/design, in which solar panels were incorporated in the design of a commerical airliner (e.g. on the wings), with the aim to reduce fuel consumption by lowering the generator workload?
If no, why not?
aircraft-design electrical-system solar-power
New contributor
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I'm not aware of any. And I can see several important reasons why not: solar panels are heavy, they're fragile, they require a lot of maintenance, they require a lot of wiring.
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– jwenting
yesterday
5
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@jwenting the actual solar panels aren't heavy at all. Most of the weight comes from structural reinforcements, which you don't need if you implement it into an existing structure such as the fuselage or wings. Nevertheless I don't think it would be worth it.
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– GittingGud
yesterday
4
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Solar energy is just a religion. The amount of energy gatherable per unit area is ... totally trivial. Indeed, the example of aircraft points out how utterly useless solar energy is. Solar cells are a fantastically ingenious invention for, say, calculators.
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– Fattie
yesterday
7
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As you include trail options, there have been at least two planes which have been powered completely by photovoltaic panels, Solar Impulse: en.wikipedia.org/wiki/Solar_Impulse it isn't commercial, isn't in anything like mass production, and is very slow, but they did do a round-the-world trip in the second one.
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– Puffafish
yesterday
29
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@Fattie Solar energy is perfectly workable on the ground, where getting 200W per square meter is fine.
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– pjc50
yesterday
|
show 8 more comments
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Has there ever been a trial/project/design, in which solar panels were incorporated in the design of a commerical airliner (e.g. on the wings), with the aim to reduce fuel consumption by lowering the generator workload?
If no, why not?
aircraft-design electrical-system solar-power
New contributor
$endgroup$
Has there ever been a trial/project/design, in which solar panels were incorporated in the design of a commerical airliner (e.g. on the wings), with the aim to reduce fuel consumption by lowering the generator workload?
If no, why not?
aircraft-design electrical-system solar-power
aircraft-design electrical-system solar-power
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edited yesterday
Steve V.
14.9k568135
14.9k568135
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asked yesterday
avsolavsol
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I'm not aware of any. And I can see several important reasons why not: solar panels are heavy, they're fragile, they require a lot of maintenance, they require a lot of wiring.
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– jwenting
yesterday
5
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@jwenting the actual solar panels aren't heavy at all. Most of the weight comes from structural reinforcements, which you don't need if you implement it into an existing structure such as the fuselage or wings. Nevertheless I don't think it would be worth it.
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– GittingGud
yesterday
4
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Solar energy is just a religion. The amount of energy gatherable per unit area is ... totally trivial. Indeed, the example of aircraft points out how utterly useless solar energy is. Solar cells are a fantastically ingenious invention for, say, calculators.
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– Fattie
yesterday
7
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As you include trail options, there have been at least two planes which have been powered completely by photovoltaic panels, Solar Impulse: en.wikipedia.org/wiki/Solar_Impulse it isn't commercial, isn't in anything like mass production, and is very slow, but they did do a round-the-world trip in the second one.
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– Puffafish
yesterday
29
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@Fattie Solar energy is perfectly workable on the ground, where getting 200W per square meter is fine.
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– pjc50
yesterday
|
show 8 more comments
7
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I'm not aware of any. And I can see several important reasons why not: solar panels are heavy, they're fragile, they require a lot of maintenance, they require a lot of wiring.
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– jwenting
yesterday
5
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@jwenting the actual solar panels aren't heavy at all. Most of the weight comes from structural reinforcements, which you don't need if you implement it into an existing structure such as the fuselage or wings. Nevertheless I don't think it would be worth it.
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– GittingGud
yesterday
4
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Solar energy is just a religion. The amount of energy gatherable per unit area is ... totally trivial. Indeed, the example of aircraft points out how utterly useless solar energy is. Solar cells are a fantastically ingenious invention for, say, calculators.
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– Fattie
yesterday
7
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As you include trail options, there have been at least two planes which have been powered completely by photovoltaic panels, Solar Impulse: en.wikipedia.org/wiki/Solar_Impulse it isn't commercial, isn't in anything like mass production, and is very slow, but they did do a round-the-world trip in the second one.
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– Puffafish
yesterday
29
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@Fattie Solar energy is perfectly workable on the ground, where getting 200W per square meter is fine.
$endgroup$
– pjc50
yesterday
7
7
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I'm not aware of any. And I can see several important reasons why not: solar panels are heavy, they're fragile, they require a lot of maintenance, they require a lot of wiring.
$endgroup$
– jwenting
yesterday
$begingroup$
I'm not aware of any. And I can see several important reasons why not: solar panels are heavy, they're fragile, they require a lot of maintenance, they require a lot of wiring.
$endgroup$
– jwenting
yesterday
5
5
$begingroup$
@jwenting the actual solar panels aren't heavy at all. Most of the weight comes from structural reinforcements, which you don't need if you implement it into an existing structure such as the fuselage or wings. Nevertheless I don't think it would be worth it.
$endgroup$
– GittingGud
yesterday
$begingroup$
@jwenting the actual solar panels aren't heavy at all. Most of the weight comes from structural reinforcements, which you don't need if you implement it into an existing structure such as the fuselage or wings. Nevertheless I don't think it would be worth it.
$endgroup$
– GittingGud
yesterday
4
4
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Solar energy is just a religion. The amount of energy gatherable per unit area is ... totally trivial. Indeed, the example of aircraft points out how utterly useless solar energy is. Solar cells are a fantastically ingenious invention for, say, calculators.
$endgroup$
– Fattie
yesterday
$begingroup$
Solar energy is just a religion. The amount of energy gatherable per unit area is ... totally trivial. Indeed, the example of aircraft points out how utterly useless solar energy is. Solar cells are a fantastically ingenious invention for, say, calculators.
$endgroup$
– Fattie
yesterday
7
7
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As you include trail options, there have been at least two planes which have been powered completely by photovoltaic panels, Solar Impulse: en.wikipedia.org/wiki/Solar_Impulse it isn't commercial, isn't in anything like mass production, and is very slow, but they did do a round-the-world trip in the second one.
$endgroup$
– Puffafish
yesterday
$begingroup$
As you include trail options, there have been at least two planes which have been powered completely by photovoltaic panels, Solar Impulse: en.wikipedia.org/wiki/Solar_Impulse it isn't commercial, isn't in anything like mass production, and is very slow, but they did do a round-the-world trip in the second one.
$endgroup$
– Puffafish
yesterday
29
29
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@Fattie Solar energy is perfectly workable on the ground, where getting 200W per square meter is fine.
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– pjc50
yesterday
$begingroup$
@Fattie Solar energy is perfectly workable on the ground, where getting 200W per square meter is fine.
$endgroup$
– pjc50
yesterday
|
show 8 more comments
6 Answers
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If no, why not?
While I can't say categorically that it's not happened, I'm pretty sure.
Solar radiance is approx. 1 kW⁄m². A 737 has approximately 100 m² wing area. Solar cells are approximately 20 % effective.
If you covered the entire wings in solar panels, that would work out to 20 kW of electrical power at best. At night, it would be close to zero extra power.
Jet fuel contains about 43 MJ⁄kg of energy (source). 20 kW is 20 kJ⁄s. For a 2-hour flight, the total energy produced would be 144 MJ, or comparable to energy in 3–4 kilograms of jet fuel.
Turbines are not 100 % efficient, so let's say that with all losses in engine, 25 % of the power in the fuel is available as electricity. That means you'd need 12 kg of fuel to provide the same amount of electricity as the solar panels.
12 kg of fuel. That's probably far less than the solar cells will weigh, probably by a factor of at least ten. In addition, the you don't have to carry around already burnt fuel, unlike solar cells, which you will have to carry around.
Edit: I found another answer on this site, that claims extra fuel use is on the order of 0.125 kg⁄kWh. I don't know if that's correct or not, nor do I really care. It doesn't change the conclusion, it only makes jet fuel even more favorable.
In short the amount of power provided by solar cells is tiny compared to the energy contained in jet fuel. And that doesn't even touch on the mechanical requirements of a wing...
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Right, although a not completely unconceivable setup would be to have thin-film cells on the wings instead of paint. Solar cells can be made very light. The more fundamental problem is that there's just not really much area available, especially with reasonably high aspect ratio wings – and lower aspect ratio would mean higher drag, which would again defeat the point.
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– leftaroundabout
yesterday
8
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The problem with generating "only" 20kW by solar panels is not only that it is a tiny proportion of the total, but it's more electrical power than you actually need most of the time. For example the battery backup system on a 737-800, designed to provide 30 minutes emergency power if all other power generators fail, is rated at less than 2kW. Adding yet another system to convert the tiny amount of "excess" solar energy into mechanical thrust would make the concept even less practical.
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– alephzero
yesterday
1
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@leftaroundabout the quality of the paint job is actually critical for the aerodynamics of the plane. Any "roughness" on the wing surface from the installation of solar cells (e.g. at the joints between sections of panel) would potentially mess up the boundary layer behaviour and reduce the stall margin.
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– alephzero
yesterday
4
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Sure, there's lot's of small reasons why it's difficult. But those could probably be solved if it was economically viable. But it's not. It's technically difficult, and there damn close to zero reason for it.
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– vidarlo
yesterday
2
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@alephzero I imagine that this power would be used mainly for non-critical systems, like passenger entertainment, WiFi, and power outlets.
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– Barmar
yesterday
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No, there are several reasons:
- Fragility v Efficiency v Weight: the most efficient solar panels are rigid and heavy, which is bad for a wing structure. Flexible and light panels do exist, but they are half as efficient. They also have limitations to how much flexing they really can take, the constant flexing of a wing, vibrations, cycles between hot and extreme cold at altitude all make it a punishing environment for that kind of technology. Covering the fuselage would mean less flexing, but then you'd only have a few panels positioned right at any one time to create electricity
- Weight: In addition to the weight of the panels themselves you have all the other technology to make them work, like regulators, power conditioners, power storage, delivery wiring
- Complexity: This is yet another system to maintain, and it would be complicated to do so. If a panel breaks you'd have to take apart the wing to get at it
- Cost: you'd need solar panels that are efficient, flexible, durable and light. That all adds up to expensive panels, far more than is worth it
- Limited window of use: Obviously solar panels are no good at night, but they are also only generate electricity when they are oriented at least partly towards the sun. If you're going to cover the wing then the sun must be a good 30-40° up before you'll get appreciable power from them
So it's a lot of weight and cost for a technology that isn't going to generate power for much of the time the airplane is in use.
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This answer is not really correct. (1) the actual answer is that solar cells provide what can only be described as "no" power, within rounding error. (2) the difficulties mentioned (cost, engineering difficulty etc) would, indeed, be instantly overcome if solar energy was 10,000x more powerful than it is (indeed everything on an aircraft is very expensive, difficult to make).
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– Fattie
yesterday
5
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I don't follow you @Fattie. Solar cells do provide power, it's why they're being installed on homes all over the place....
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– GdD
yesterday
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They provide a minuscul amount of power, in terms of the question asked though. Consider vid's answer. At the absolute theoretical max it would provide the equivalent of "a few KG" of jet fuel. (!) That's why I said it is zero within rounding error.
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– Fattie
yesterday
9
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There's more than one aspect to this @Fattie, and there was no point in repeating vidarlo's answer.
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– GdD
yesterday
add a comment |
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Not purely on topic but there is a solar airplane. Solar supported airliner isn't out of the realm of possibilities, just solar tech isn't there yet. Also it would have to be economically feasible to even be considered.
Here's an article from 2016 about a solar airplane that traveled the globe.
https://www.theguardian.com/environment/2016/jul/26/solar-impulse-plane-makes-history-completing-round-the-world-trip
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Solar Impulse 2 is basically covered in solar panels of probably at least 20% efficiency. This gives it enough power to fly with just a single pilot, at about 60 mph during the day, or 30 mph on batteries at night. Even with 100% efficient panels, that's still nowhere near the power to carry a cabin full of people at much higher speeds. Modern high-speed air travel uses a ridiculous amount of energy; that's why it creates so much greenhouse gas emissions. It would be nice if solar flight were viable for airliners, but it doesn't look like it ever will be.
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– Peter Cordes
yesterday
1
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"just solar tech isn't there yet" - that's not the problem. Even if solar panels were 100% efficient, they (and all the wiring, the motors they drive, etc.) would still weight much more than the tiny amount of fuel holding the same amount of energy. Solar panels make sense on the ground, where you have a lot of area and weight is not a big problem. Even if technology advances by ludicrous amounts to make solar powered airliners possible, the panels won't be on the plane, the solar power will be generated on the ground, and stored in batteries or fuel cells to be loaded unto the aircraft.
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– vsz
23 hours ago
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It is on topic enough! And still, if a plane with a wingspan of a 747 can carry one person, then a plane with a double that wingspan can carry 2 persons. The thing is how to combine wingspan with lift. Is there a limit to wingspan? One possible solution is unfoldable wings or a kind of sail that doesn't drag. In 100 years or less oil will be gone, and I guess people will still wanna fly.
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– GwenKillerby
11 hours ago
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@GwenKillerby : No, that's not how it works. Oil will never be completely gone. The oil reserves of the planet are not like the fuel in your car, that you drive and then at one point the car suddenly stops because fuel just ran out. As we use up the more economically extractable oil, it will become progressively more and more expensive. When it gets expensive enough, we will use less and less of it. There are many alternatives to oil, it's just that oil is so much cheaper. Once it gets expensive enough, it will be gradually replaced, first where it is easier to do so.
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– vsz
7 hours ago
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For air travel oil is much more difficult (with current technology nearly impossible) to replace, so oil will be probably used for longer, and it will last longer because other industries will use less of it. And after that, either some currently inconceivable technology will be discovered, or we will continue to use oils extracted by other means, maybe from crops.
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– vsz
7 hours ago
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I once worked for a company that made electronics for commercial aircraft (flight deck printers, Ethernet switches, digital chart recorders).
In addition to what others have mentioned on this thread, you also have to account for the fact that if a product is manufactured for aircraft in the US, it must comply AS9100 and FAR, and whatever standard the EU is using nowadays. This includes rigorous testing to ensure that, not only is the device safe, but also that the device will not interfere with any of the critical systems of the aircraft.
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How is this related to the question? Solar power is a pretty simple source of electricity to deal with compared to everything else, especially compared to a generator.
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– pipe
21 hours ago
add a comment |
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One consideration that makes solar aircraft less feasible is that the figure of 1kw/m2 is for sunlight striking the solar panel square on - i.e. perpendicular to the panel. Unless you're flying in the tropics at noon, an aircraft's wings won't meet that. Their insolation (the amount of power from sunlight) drops with the cosine of the angle from vertical incidence.
Regarding doubling 747 wingspan for two seats - how many passengers will settle for a 45 MPH / 39 knot / 72 kph flight speed (i.e. New York to London in 77 hours if no headwind)?
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I suspect that even if it were only attempting to reduce the generator load, the cost vs benefit for this kind of use would just not yield a positive return. The demand-rate is just too high.
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This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
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– Pondlife
4 hours ago
add a comment |
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If no, why not?
While I can't say categorically that it's not happened, I'm pretty sure.
Solar radiance is approx. 1 kW⁄m². A 737 has approximately 100 m² wing area. Solar cells are approximately 20 % effective.
If you covered the entire wings in solar panels, that would work out to 20 kW of electrical power at best. At night, it would be close to zero extra power.
Jet fuel contains about 43 MJ⁄kg of energy (source). 20 kW is 20 kJ⁄s. For a 2-hour flight, the total energy produced would be 144 MJ, or comparable to energy in 3–4 kilograms of jet fuel.
Turbines are not 100 % efficient, so let's say that with all losses in engine, 25 % of the power in the fuel is available as electricity. That means you'd need 12 kg of fuel to provide the same amount of electricity as the solar panels.
12 kg of fuel. That's probably far less than the solar cells will weigh, probably by a factor of at least ten. In addition, the you don't have to carry around already burnt fuel, unlike solar cells, which you will have to carry around.
Edit: I found another answer on this site, that claims extra fuel use is on the order of 0.125 kg⁄kWh. I don't know if that's correct or not, nor do I really care. It doesn't change the conclusion, it only makes jet fuel even more favorable.
In short the amount of power provided by solar cells is tiny compared to the energy contained in jet fuel. And that doesn't even touch on the mechanical requirements of a wing...
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1
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Right, although a not completely unconceivable setup would be to have thin-film cells on the wings instead of paint. Solar cells can be made very light. The more fundamental problem is that there's just not really much area available, especially with reasonably high aspect ratio wings – and lower aspect ratio would mean higher drag, which would again defeat the point.
$endgroup$
– leftaroundabout
yesterday
8
$begingroup$
The problem with generating "only" 20kW by solar panels is not only that it is a tiny proportion of the total, but it's more electrical power than you actually need most of the time. For example the battery backup system on a 737-800, designed to provide 30 minutes emergency power if all other power generators fail, is rated at less than 2kW. Adding yet another system to convert the tiny amount of "excess" solar energy into mechanical thrust would make the concept even less practical.
$endgroup$
– alephzero
yesterday
1
$begingroup$
@leftaroundabout the quality of the paint job is actually critical for the aerodynamics of the plane. Any "roughness" on the wing surface from the installation of solar cells (e.g. at the joints between sections of panel) would potentially mess up the boundary layer behaviour and reduce the stall margin.
$endgroup$
– alephzero
yesterday
4
$begingroup$
Sure, there's lot's of small reasons why it's difficult. But those could probably be solved if it was economically viable. But it's not. It's technically difficult, and there damn close to zero reason for it.
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– vidarlo
yesterday
2
$begingroup$
@alephzero I imagine that this power would be used mainly for non-critical systems, like passenger entertainment, WiFi, and power outlets.
$endgroup$
– Barmar
yesterday
|
show 8 more comments
$begingroup$
If no, why not?
While I can't say categorically that it's not happened, I'm pretty sure.
Solar radiance is approx. 1 kW⁄m². A 737 has approximately 100 m² wing area. Solar cells are approximately 20 % effective.
If you covered the entire wings in solar panels, that would work out to 20 kW of electrical power at best. At night, it would be close to zero extra power.
Jet fuel contains about 43 MJ⁄kg of energy (source). 20 kW is 20 kJ⁄s. For a 2-hour flight, the total energy produced would be 144 MJ, or comparable to energy in 3–4 kilograms of jet fuel.
Turbines are not 100 % efficient, so let's say that with all losses in engine, 25 % of the power in the fuel is available as electricity. That means you'd need 12 kg of fuel to provide the same amount of electricity as the solar panels.
12 kg of fuel. That's probably far less than the solar cells will weigh, probably by a factor of at least ten. In addition, the you don't have to carry around already burnt fuel, unlike solar cells, which you will have to carry around.
Edit: I found another answer on this site, that claims extra fuel use is on the order of 0.125 kg⁄kWh. I don't know if that's correct or not, nor do I really care. It doesn't change the conclusion, it only makes jet fuel even more favorable.
In short the amount of power provided by solar cells is tiny compared to the energy contained in jet fuel. And that doesn't even touch on the mechanical requirements of a wing...
$endgroup$
1
$begingroup$
Right, although a not completely unconceivable setup would be to have thin-film cells on the wings instead of paint. Solar cells can be made very light. The more fundamental problem is that there's just not really much area available, especially with reasonably high aspect ratio wings – and lower aspect ratio would mean higher drag, which would again defeat the point.
$endgroup$
– leftaroundabout
yesterday
8
$begingroup$
The problem with generating "only" 20kW by solar panels is not only that it is a tiny proportion of the total, but it's more electrical power than you actually need most of the time. For example the battery backup system on a 737-800, designed to provide 30 minutes emergency power if all other power generators fail, is rated at less than 2kW. Adding yet another system to convert the tiny amount of "excess" solar energy into mechanical thrust would make the concept even less practical.
$endgroup$
– alephzero
yesterday
1
$begingroup$
@leftaroundabout the quality of the paint job is actually critical for the aerodynamics of the plane. Any "roughness" on the wing surface from the installation of solar cells (e.g. at the joints between sections of panel) would potentially mess up the boundary layer behaviour and reduce the stall margin.
$endgroup$
– alephzero
yesterday
4
$begingroup$
Sure, there's lot's of small reasons why it's difficult. But those could probably be solved if it was economically viable. But it's not. It's technically difficult, and there damn close to zero reason for it.
$endgroup$
– vidarlo
yesterday
2
$begingroup$
@alephzero I imagine that this power would be used mainly for non-critical systems, like passenger entertainment, WiFi, and power outlets.
$endgroup$
– Barmar
yesterday
|
show 8 more comments
$begingroup$
If no, why not?
While I can't say categorically that it's not happened, I'm pretty sure.
Solar radiance is approx. 1 kW⁄m². A 737 has approximately 100 m² wing area. Solar cells are approximately 20 % effective.
If you covered the entire wings in solar panels, that would work out to 20 kW of electrical power at best. At night, it would be close to zero extra power.
Jet fuel contains about 43 MJ⁄kg of energy (source). 20 kW is 20 kJ⁄s. For a 2-hour flight, the total energy produced would be 144 MJ, or comparable to energy in 3–4 kilograms of jet fuel.
Turbines are not 100 % efficient, so let's say that with all losses in engine, 25 % of the power in the fuel is available as electricity. That means you'd need 12 kg of fuel to provide the same amount of electricity as the solar panels.
12 kg of fuel. That's probably far less than the solar cells will weigh, probably by a factor of at least ten. In addition, the you don't have to carry around already burnt fuel, unlike solar cells, which you will have to carry around.
Edit: I found another answer on this site, that claims extra fuel use is on the order of 0.125 kg⁄kWh. I don't know if that's correct or not, nor do I really care. It doesn't change the conclusion, it only makes jet fuel even more favorable.
In short the amount of power provided by solar cells is tiny compared to the energy contained in jet fuel. And that doesn't even touch on the mechanical requirements of a wing...
$endgroup$
If no, why not?
While I can't say categorically that it's not happened, I'm pretty sure.
Solar radiance is approx. 1 kW⁄m². A 737 has approximately 100 m² wing area. Solar cells are approximately 20 % effective.
If you covered the entire wings in solar panels, that would work out to 20 kW of electrical power at best. At night, it would be close to zero extra power.
Jet fuel contains about 43 MJ⁄kg of energy (source). 20 kW is 20 kJ⁄s. For a 2-hour flight, the total energy produced would be 144 MJ, or comparable to energy in 3–4 kilograms of jet fuel.
Turbines are not 100 % efficient, so let's say that with all losses in engine, 25 % of the power in the fuel is available as electricity. That means you'd need 12 kg of fuel to provide the same amount of electricity as the solar panels.
12 kg of fuel. That's probably far less than the solar cells will weigh, probably by a factor of at least ten. In addition, the you don't have to carry around already burnt fuel, unlike solar cells, which you will have to carry around.
Edit: I found another answer on this site, that claims extra fuel use is on the order of 0.125 kg⁄kWh. I don't know if that's correct or not, nor do I really care. It doesn't change the conclusion, it only makes jet fuel even more favorable.
In short the amount of power provided by solar cells is tiny compared to the energy contained in jet fuel. And that doesn't even touch on the mechanical requirements of a wing...
edited 11 hours ago
Joey
1053
1053
answered yesterday
vidarlovidarlo
1,012614
1,012614
1
$begingroup$
Right, although a not completely unconceivable setup would be to have thin-film cells on the wings instead of paint. Solar cells can be made very light. The more fundamental problem is that there's just not really much area available, especially with reasonably high aspect ratio wings – and lower aspect ratio would mean higher drag, which would again defeat the point.
$endgroup$
– leftaroundabout
yesterday
8
$begingroup$
The problem with generating "only" 20kW by solar panels is not only that it is a tiny proportion of the total, but it's more electrical power than you actually need most of the time. For example the battery backup system on a 737-800, designed to provide 30 minutes emergency power if all other power generators fail, is rated at less than 2kW. Adding yet another system to convert the tiny amount of "excess" solar energy into mechanical thrust would make the concept even less practical.
$endgroup$
– alephzero
yesterday
1
$begingroup$
@leftaroundabout the quality of the paint job is actually critical for the aerodynamics of the plane. Any "roughness" on the wing surface from the installation of solar cells (e.g. at the joints between sections of panel) would potentially mess up the boundary layer behaviour and reduce the stall margin.
$endgroup$
– alephzero
yesterday
4
$begingroup$
Sure, there's lot's of small reasons why it's difficult. But those could probably be solved if it was economically viable. But it's not. It's technically difficult, and there damn close to zero reason for it.
$endgroup$
– vidarlo
yesterday
2
$begingroup$
@alephzero I imagine that this power would be used mainly for non-critical systems, like passenger entertainment, WiFi, and power outlets.
$endgroup$
– Barmar
yesterday
|
show 8 more comments
1
$begingroup$
Right, although a not completely unconceivable setup would be to have thin-film cells on the wings instead of paint. Solar cells can be made very light. The more fundamental problem is that there's just not really much area available, especially with reasonably high aspect ratio wings – and lower aspect ratio would mean higher drag, which would again defeat the point.
$endgroup$
– leftaroundabout
yesterday
8
$begingroup$
The problem with generating "only" 20kW by solar panels is not only that it is a tiny proportion of the total, but it's more electrical power than you actually need most of the time. For example the battery backup system on a 737-800, designed to provide 30 minutes emergency power if all other power generators fail, is rated at less than 2kW. Adding yet another system to convert the tiny amount of "excess" solar energy into mechanical thrust would make the concept even less practical.
$endgroup$
– alephzero
yesterday
1
$begingroup$
@leftaroundabout the quality of the paint job is actually critical for the aerodynamics of the plane. Any "roughness" on the wing surface from the installation of solar cells (e.g. at the joints between sections of panel) would potentially mess up the boundary layer behaviour and reduce the stall margin.
$endgroup$
– alephzero
yesterday
4
$begingroup$
Sure, there's lot's of small reasons why it's difficult. But those could probably be solved if it was economically viable. But it's not. It's technically difficult, and there damn close to zero reason for it.
$endgroup$
– vidarlo
yesterday
2
$begingroup$
@alephzero I imagine that this power would be used mainly for non-critical systems, like passenger entertainment, WiFi, and power outlets.
$endgroup$
– Barmar
yesterday
1
1
$begingroup$
Right, although a not completely unconceivable setup would be to have thin-film cells on the wings instead of paint. Solar cells can be made very light. The more fundamental problem is that there's just not really much area available, especially with reasonably high aspect ratio wings – and lower aspect ratio would mean higher drag, which would again defeat the point.
$endgroup$
– leftaroundabout
yesterday
$begingroup$
Right, although a not completely unconceivable setup would be to have thin-film cells on the wings instead of paint. Solar cells can be made very light. The more fundamental problem is that there's just not really much area available, especially with reasonably high aspect ratio wings – and lower aspect ratio would mean higher drag, which would again defeat the point.
$endgroup$
– leftaroundabout
yesterday
8
8
$begingroup$
The problem with generating "only" 20kW by solar panels is not only that it is a tiny proportion of the total, but it's more electrical power than you actually need most of the time. For example the battery backup system on a 737-800, designed to provide 30 minutes emergency power if all other power generators fail, is rated at less than 2kW. Adding yet another system to convert the tiny amount of "excess" solar energy into mechanical thrust would make the concept even less practical.
$endgroup$
– alephzero
yesterday
$begingroup$
The problem with generating "only" 20kW by solar panels is not only that it is a tiny proportion of the total, but it's more electrical power than you actually need most of the time. For example the battery backup system on a 737-800, designed to provide 30 minutes emergency power if all other power generators fail, is rated at less than 2kW. Adding yet another system to convert the tiny amount of "excess" solar energy into mechanical thrust would make the concept even less practical.
$endgroup$
– alephzero
yesterday
1
1
$begingroup$
@leftaroundabout the quality of the paint job is actually critical for the aerodynamics of the plane. Any "roughness" on the wing surface from the installation of solar cells (e.g. at the joints between sections of panel) would potentially mess up the boundary layer behaviour and reduce the stall margin.
$endgroup$
– alephzero
yesterday
$begingroup$
@leftaroundabout the quality of the paint job is actually critical for the aerodynamics of the plane. Any "roughness" on the wing surface from the installation of solar cells (e.g. at the joints between sections of panel) would potentially mess up the boundary layer behaviour and reduce the stall margin.
$endgroup$
– alephzero
yesterday
4
4
$begingroup$
Sure, there's lot's of small reasons why it's difficult. But those could probably be solved if it was economically viable. But it's not. It's technically difficult, and there damn close to zero reason for it.
$endgroup$
– vidarlo
yesterday
$begingroup$
Sure, there's lot's of small reasons why it's difficult. But those could probably be solved if it was economically viable. But it's not. It's technically difficult, and there damn close to zero reason for it.
$endgroup$
– vidarlo
yesterday
2
2
$begingroup$
@alephzero I imagine that this power would be used mainly for non-critical systems, like passenger entertainment, WiFi, and power outlets.
$endgroup$
– Barmar
yesterday
$begingroup$
@alephzero I imagine that this power would be used mainly for non-critical systems, like passenger entertainment, WiFi, and power outlets.
$endgroup$
– Barmar
yesterday
|
show 8 more comments
$begingroup$
No, there are several reasons:
- Fragility v Efficiency v Weight: the most efficient solar panels are rigid and heavy, which is bad for a wing structure. Flexible and light panels do exist, but they are half as efficient. They also have limitations to how much flexing they really can take, the constant flexing of a wing, vibrations, cycles between hot and extreme cold at altitude all make it a punishing environment for that kind of technology. Covering the fuselage would mean less flexing, but then you'd only have a few panels positioned right at any one time to create electricity
- Weight: In addition to the weight of the panels themselves you have all the other technology to make them work, like regulators, power conditioners, power storage, delivery wiring
- Complexity: This is yet another system to maintain, and it would be complicated to do so. If a panel breaks you'd have to take apart the wing to get at it
- Cost: you'd need solar panels that are efficient, flexible, durable and light. That all adds up to expensive panels, far more than is worth it
- Limited window of use: Obviously solar panels are no good at night, but they are also only generate electricity when they are oriented at least partly towards the sun. If you're going to cover the wing then the sun must be a good 30-40° up before you'll get appreciable power from them
So it's a lot of weight and cost for a technology that isn't going to generate power for much of the time the airplane is in use.
$endgroup$
2
$begingroup$
This answer is not really correct. (1) the actual answer is that solar cells provide what can only be described as "no" power, within rounding error. (2) the difficulties mentioned (cost, engineering difficulty etc) would, indeed, be instantly overcome if solar energy was 10,000x more powerful than it is (indeed everything on an aircraft is very expensive, difficult to make).
$endgroup$
– Fattie
yesterday
5
$begingroup$
I don't follow you @Fattie. Solar cells do provide power, it's why they're being installed on homes all over the place....
$endgroup$
– GdD
yesterday
$begingroup$
They provide a minuscul amount of power, in terms of the question asked though. Consider vid's answer. At the absolute theoretical max it would provide the equivalent of "a few KG" of jet fuel. (!) That's why I said it is zero within rounding error.
$endgroup$
– Fattie
yesterday
9
$begingroup$
There's more than one aspect to this @Fattie, and there was no point in repeating vidarlo's answer.
$endgroup$
– GdD
yesterday
add a comment |
$begingroup$
No, there are several reasons:
- Fragility v Efficiency v Weight: the most efficient solar panels are rigid and heavy, which is bad for a wing structure. Flexible and light panels do exist, but they are half as efficient. They also have limitations to how much flexing they really can take, the constant flexing of a wing, vibrations, cycles between hot and extreme cold at altitude all make it a punishing environment for that kind of technology. Covering the fuselage would mean less flexing, but then you'd only have a few panels positioned right at any one time to create electricity
- Weight: In addition to the weight of the panels themselves you have all the other technology to make them work, like regulators, power conditioners, power storage, delivery wiring
- Complexity: This is yet another system to maintain, and it would be complicated to do so. If a panel breaks you'd have to take apart the wing to get at it
- Cost: you'd need solar panels that are efficient, flexible, durable and light. That all adds up to expensive panels, far more than is worth it
- Limited window of use: Obviously solar panels are no good at night, but they are also only generate electricity when they are oriented at least partly towards the sun. If you're going to cover the wing then the sun must be a good 30-40° up before you'll get appreciable power from them
So it's a lot of weight and cost for a technology that isn't going to generate power for much of the time the airplane is in use.
$endgroup$
2
$begingroup$
This answer is not really correct. (1) the actual answer is that solar cells provide what can only be described as "no" power, within rounding error. (2) the difficulties mentioned (cost, engineering difficulty etc) would, indeed, be instantly overcome if solar energy was 10,000x more powerful than it is (indeed everything on an aircraft is very expensive, difficult to make).
$endgroup$
– Fattie
yesterday
5
$begingroup$
I don't follow you @Fattie. Solar cells do provide power, it's why they're being installed on homes all over the place....
$endgroup$
– GdD
yesterday
$begingroup$
They provide a minuscul amount of power, in terms of the question asked though. Consider vid's answer. At the absolute theoretical max it would provide the equivalent of "a few KG" of jet fuel. (!) That's why I said it is zero within rounding error.
$endgroup$
– Fattie
yesterday
9
$begingroup$
There's more than one aspect to this @Fattie, and there was no point in repeating vidarlo's answer.
$endgroup$
– GdD
yesterday
add a comment |
$begingroup$
No, there are several reasons:
- Fragility v Efficiency v Weight: the most efficient solar panels are rigid and heavy, which is bad for a wing structure. Flexible and light panels do exist, but they are half as efficient. They also have limitations to how much flexing they really can take, the constant flexing of a wing, vibrations, cycles between hot and extreme cold at altitude all make it a punishing environment for that kind of technology. Covering the fuselage would mean less flexing, but then you'd only have a few panels positioned right at any one time to create electricity
- Weight: In addition to the weight of the panels themselves you have all the other technology to make them work, like regulators, power conditioners, power storage, delivery wiring
- Complexity: This is yet another system to maintain, and it would be complicated to do so. If a panel breaks you'd have to take apart the wing to get at it
- Cost: you'd need solar panels that are efficient, flexible, durable and light. That all adds up to expensive panels, far more than is worth it
- Limited window of use: Obviously solar panels are no good at night, but they are also only generate electricity when they are oriented at least partly towards the sun. If you're going to cover the wing then the sun must be a good 30-40° up before you'll get appreciable power from them
So it's a lot of weight and cost for a technology that isn't going to generate power for much of the time the airplane is in use.
$endgroup$
No, there are several reasons:
- Fragility v Efficiency v Weight: the most efficient solar panels are rigid and heavy, which is bad for a wing structure. Flexible and light panels do exist, but they are half as efficient. They also have limitations to how much flexing they really can take, the constant flexing of a wing, vibrations, cycles between hot and extreme cold at altitude all make it a punishing environment for that kind of technology. Covering the fuselage would mean less flexing, but then you'd only have a few panels positioned right at any one time to create electricity
- Weight: In addition to the weight of the panels themselves you have all the other technology to make them work, like regulators, power conditioners, power storage, delivery wiring
- Complexity: This is yet another system to maintain, and it would be complicated to do so. If a panel breaks you'd have to take apart the wing to get at it
- Cost: you'd need solar panels that are efficient, flexible, durable and light. That all adds up to expensive panels, far more than is worth it
- Limited window of use: Obviously solar panels are no good at night, but they are also only generate electricity when they are oriented at least partly towards the sun. If you're going to cover the wing then the sun must be a good 30-40° up before you'll get appreciable power from them
So it's a lot of weight and cost for a technology that isn't going to generate power for much of the time the airplane is in use.
edited 7 hours ago
AndroidSmoker74
21110
21110
answered yesterday
GdDGdD
32.4k386135
32.4k386135
2
$begingroup$
This answer is not really correct. (1) the actual answer is that solar cells provide what can only be described as "no" power, within rounding error. (2) the difficulties mentioned (cost, engineering difficulty etc) would, indeed, be instantly overcome if solar energy was 10,000x more powerful than it is (indeed everything on an aircraft is very expensive, difficult to make).
$endgroup$
– Fattie
yesterday
5
$begingroup$
I don't follow you @Fattie. Solar cells do provide power, it's why they're being installed on homes all over the place....
$endgroup$
– GdD
yesterday
$begingroup$
They provide a minuscul amount of power, in terms of the question asked though. Consider vid's answer. At the absolute theoretical max it would provide the equivalent of "a few KG" of jet fuel. (!) That's why I said it is zero within rounding error.
$endgroup$
– Fattie
yesterday
9
$begingroup$
There's more than one aspect to this @Fattie, and there was no point in repeating vidarlo's answer.
$endgroup$
– GdD
yesterday
add a comment |
2
$begingroup$
This answer is not really correct. (1) the actual answer is that solar cells provide what can only be described as "no" power, within rounding error. (2) the difficulties mentioned (cost, engineering difficulty etc) would, indeed, be instantly overcome if solar energy was 10,000x more powerful than it is (indeed everything on an aircraft is very expensive, difficult to make).
$endgroup$
– Fattie
yesterday
5
$begingroup$
I don't follow you @Fattie. Solar cells do provide power, it's why they're being installed on homes all over the place....
$endgroup$
– GdD
yesterday
$begingroup$
They provide a minuscul amount of power, in terms of the question asked though. Consider vid's answer. At the absolute theoretical max it would provide the equivalent of "a few KG" of jet fuel. (!) That's why I said it is zero within rounding error.
$endgroup$
– Fattie
yesterday
9
$begingroup$
There's more than one aspect to this @Fattie, and there was no point in repeating vidarlo's answer.
$endgroup$
– GdD
yesterday
2
2
$begingroup$
This answer is not really correct. (1) the actual answer is that solar cells provide what can only be described as "no" power, within rounding error. (2) the difficulties mentioned (cost, engineering difficulty etc) would, indeed, be instantly overcome if solar energy was 10,000x more powerful than it is (indeed everything on an aircraft is very expensive, difficult to make).
$endgroup$
– Fattie
yesterday
$begingroup$
This answer is not really correct. (1) the actual answer is that solar cells provide what can only be described as "no" power, within rounding error. (2) the difficulties mentioned (cost, engineering difficulty etc) would, indeed, be instantly overcome if solar energy was 10,000x more powerful than it is (indeed everything on an aircraft is very expensive, difficult to make).
$endgroup$
– Fattie
yesterday
5
5
$begingroup$
I don't follow you @Fattie. Solar cells do provide power, it's why they're being installed on homes all over the place....
$endgroup$
– GdD
yesterday
$begingroup$
I don't follow you @Fattie. Solar cells do provide power, it's why they're being installed on homes all over the place....
$endgroup$
– GdD
yesterday
$begingroup$
They provide a minuscul amount of power, in terms of the question asked though. Consider vid's answer. At the absolute theoretical max it would provide the equivalent of "a few KG" of jet fuel. (!) That's why I said it is zero within rounding error.
$endgroup$
– Fattie
yesterday
$begingroup$
They provide a minuscul amount of power, in terms of the question asked though. Consider vid's answer. At the absolute theoretical max it would provide the equivalent of "a few KG" of jet fuel. (!) That's why I said it is zero within rounding error.
$endgroup$
– Fattie
yesterday
9
9
$begingroup$
There's more than one aspect to this @Fattie, and there was no point in repeating vidarlo's answer.
$endgroup$
– GdD
yesterday
$begingroup$
There's more than one aspect to this @Fattie, and there was no point in repeating vidarlo's answer.
$endgroup$
– GdD
yesterday
add a comment |
$begingroup$
Not purely on topic but there is a solar airplane. Solar supported airliner isn't out of the realm of possibilities, just solar tech isn't there yet. Also it would have to be economically feasible to even be considered.
Here's an article from 2016 about a solar airplane that traveled the globe.
https://www.theguardian.com/environment/2016/jul/26/solar-impulse-plane-makes-history-completing-round-the-world-trip
New contributor
$endgroup$
3
$begingroup$
Solar Impulse 2 is basically covered in solar panels of probably at least 20% efficiency. This gives it enough power to fly with just a single pilot, at about 60 mph during the day, or 30 mph on batteries at night. Even with 100% efficient panels, that's still nowhere near the power to carry a cabin full of people at much higher speeds. Modern high-speed air travel uses a ridiculous amount of energy; that's why it creates so much greenhouse gas emissions. It would be nice if solar flight were viable for airliners, but it doesn't look like it ever will be.
$endgroup$
– Peter Cordes
yesterday
1
$begingroup$
"just solar tech isn't there yet" - that's not the problem. Even if solar panels were 100% efficient, they (and all the wiring, the motors they drive, etc.) would still weight much more than the tiny amount of fuel holding the same amount of energy. Solar panels make sense on the ground, where you have a lot of area and weight is not a big problem. Even if technology advances by ludicrous amounts to make solar powered airliners possible, the panels won't be on the plane, the solar power will be generated on the ground, and stored in batteries or fuel cells to be loaded unto the aircraft.
$endgroup$
– vsz
23 hours ago
$begingroup$
It is on topic enough! And still, if a plane with a wingspan of a 747 can carry one person, then a plane with a double that wingspan can carry 2 persons. The thing is how to combine wingspan with lift. Is there a limit to wingspan? One possible solution is unfoldable wings or a kind of sail that doesn't drag. In 100 years or less oil will be gone, and I guess people will still wanna fly.
$endgroup$
– GwenKillerby
11 hours ago
$begingroup$
@GwenKillerby : No, that's not how it works. Oil will never be completely gone. The oil reserves of the planet are not like the fuel in your car, that you drive and then at one point the car suddenly stops because fuel just ran out. As we use up the more economically extractable oil, it will become progressively more and more expensive. When it gets expensive enough, we will use less and less of it. There are many alternatives to oil, it's just that oil is so much cheaper. Once it gets expensive enough, it will be gradually replaced, first where it is easier to do so.
$endgroup$
– vsz
7 hours ago
$begingroup$
For air travel oil is much more difficult (with current technology nearly impossible) to replace, so oil will be probably used for longer, and it will last longer because other industries will use less of it. And after that, either some currently inconceivable technology will be discovered, or we will continue to use oils extracted by other means, maybe from crops.
$endgroup$
– vsz
7 hours ago
|
show 1 more comment
$begingroup$
Not purely on topic but there is a solar airplane. Solar supported airliner isn't out of the realm of possibilities, just solar tech isn't there yet. Also it would have to be economically feasible to even be considered.
Here's an article from 2016 about a solar airplane that traveled the globe.
https://www.theguardian.com/environment/2016/jul/26/solar-impulse-plane-makes-history-completing-round-the-world-trip
New contributor
$endgroup$
3
$begingroup$
Solar Impulse 2 is basically covered in solar panels of probably at least 20% efficiency. This gives it enough power to fly with just a single pilot, at about 60 mph during the day, or 30 mph on batteries at night. Even with 100% efficient panels, that's still nowhere near the power to carry a cabin full of people at much higher speeds. Modern high-speed air travel uses a ridiculous amount of energy; that's why it creates so much greenhouse gas emissions. It would be nice if solar flight were viable for airliners, but it doesn't look like it ever will be.
$endgroup$
– Peter Cordes
yesterday
1
$begingroup$
"just solar tech isn't there yet" - that's not the problem. Even if solar panels were 100% efficient, they (and all the wiring, the motors they drive, etc.) would still weight much more than the tiny amount of fuel holding the same amount of energy. Solar panels make sense on the ground, where you have a lot of area and weight is not a big problem. Even if technology advances by ludicrous amounts to make solar powered airliners possible, the panels won't be on the plane, the solar power will be generated on the ground, and stored in batteries or fuel cells to be loaded unto the aircraft.
$endgroup$
– vsz
23 hours ago
$begingroup$
It is on topic enough! And still, if a plane with a wingspan of a 747 can carry one person, then a plane with a double that wingspan can carry 2 persons. The thing is how to combine wingspan with lift. Is there a limit to wingspan? One possible solution is unfoldable wings or a kind of sail that doesn't drag. In 100 years or less oil will be gone, and I guess people will still wanna fly.
$endgroup$
– GwenKillerby
11 hours ago
$begingroup$
@GwenKillerby : No, that's not how it works. Oil will never be completely gone. The oil reserves of the planet are not like the fuel in your car, that you drive and then at one point the car suddenly stops because fuel just ran out. As we use up the more economically extractable oil, it will become progressively more and more expensive. When it gets expensive enough, we will use less and less of it. There are many alternatives to oil, it's just that oil is so much cheaper. Once it gets expensive enough, it will be gradually replaced, first where it is easier to do so.
$endgroup$
– vsz
7 hours ago
$begingroup$
For air travel oil is much more difficult (with current technology nearly impossible) to replace, so oil will be probably used for longer, and it will last longer because other industries will use less of it. And after that, either some currently inconceivable technology will be discovered, or we will continue to use oils extracted by other means, maybe from crops.
$endgroup$
– vsz
7 hours ago
|
show 1 more comment
$begingroup$
Not purely on topic but there is a solar airplane. Solar supported airliner isn't out of the realm of possibilities, just solar tech isn't there yet. Also it would have to be economically feasible to even be considered.
Here's an article from 2016 about a solar airplane that traveled the globe.
https://www.theguardian.com/environment/2016/jul/26/solar-impulse-plane-makes-history-completing-round-the-world-trip
New contributor
$endgroup$
Not purely on topic but there is a solar airplane. Solar supported airliner isn't out of the realm of possibilities, just solar tech isn't there yet. Also it would have to be economically feasible to even be considered.
Here's an article from 2016 about a solar airplane that traveled the globe.
https://www.theguardian.com/environment/2016/jul/26/solar-impulse-plane-makes-history-completing-round-the-world-trip
New contributor
New contributor
answered yesterday
MertymanMertyman
471
471
New contributor
New contributor
3
$begingroup$
Solar Impulse 2 is basically covered in solar panels of probably at least 20% efficiency. This gives it enough power to fly with just a single pilot, at about 60 mph during the day, or 30 mph on batteries at night. Even with 100% efficient panels, that's still nowhere near the power to carry a cabin full of people at much higher speeds. Modern high-speed air travel uses a ridiculous amount of energy; that's why it creates so much greenhouse gas emissions. It would be nice if solar flight were viable for airliners, but it doesn't look like it ever will be.
$endgroup$
– Peter Cordes
yesterday
1
$begingroup$
"just solar tech isn't there yet" - that's not the problem. Even if solar panels were 100% efficient, they (and all the wiring, the motors they drive, etc.) would still weight much more than the tiny amount of fuel holding the same amount of energy. Solar panels make sense on the ground, where you have a lot of area and weight is not a big problem. Even if technology advances by ludicrous amounts to make solar powered airliners possible, the panels won't be on the plane, the solar power will be generated on the ground, and stored in batteries or fuel cells to be loaded unto the aircraft.
$endgroup$
– vsz
23 hours ago
$begingroup$
It is on topic enough! And still, if a plane with a wingspan of a 747 can carry one person, then a plane with a double that wingspan can carry 2 persons. The thing is how to combine wingspan with lift. Is there a limit to wingspan? One possible solution is unfoldable wings or a kind of sail that doesn't drag. In 100 years or less oil will be gone, and I guess people will still wanna fly.
$endgroup$
– GwenKillerby
11 hours ago
$begingroup$
@GwenKillerby : No, that's not how it works. Oil will never be completely gone. The oil reserves of the planet are not like the fuel in your car, that you drive and then at one point the car suddenly stops because fuel just ran out. As we use up the more economically extractable oil, it will become progressively more and more expensive. When it gets expensive enough, we will use less and less of it. There are many alternatives to oil, it's just that oil is so much cheaper. Once it gets expensive enough, it will be gradually replaced, first where it is easier to do so.
$endgroup$
– vsz
7 hours ago
$begingroup$
For air travel oil is much more difficult (with current technology nearly impossible) to replace, so oil will be probably used for longer, and it will last longer because other industries will use less of it. And after that, either some currently inconceivable technology will be discovered, or we will continue to use oils extracted by other means, maybe from crops.
$endgroup$
– vsz
7 hours ago
|
show 1 more comment
3
$begingroup$
Solar Impulse 2 is basically covered in solar panels of probably at least 20% efficiency. This gives it enough power to fly with just a single pilot, at about 60 mph during the day, or 30 mph on batteries at night. Even with 100% efficient panels, that's still nowhere near the power to carry a cabin full of people at much higher speeds. Modern high-speed air travel uses a ridiculous amount of energy; that's why it creates so much greenhouse gas emissions. It would be nice if solar flight were viable for airliners, but it doesn't look like it ever will be.
$endgroup$
– Peter Cordes
yesterday
1
$begingroup$
"just solar tech isn't there yet" - that's not the problem. Even if solar panels were 100% efficient, they (and all the wiring, the motors they drive, etc.) would still weight much more than the tiny amount of fuel holding the same amount of energy. Solar panels make sense on the ground, where you have a lot of area and weight is not a big problem. Even if technology advances by ludicrous amounts to make solar powered airliners possible, the panels won't be on the plane, the solar power will be generated on the ground, and stored in batteries or fuel cells to be loaded unto the aircraft.
$endgroup$
– vsz
23 hours ago
$begingroup$
It is on topic enough! And still, if a plane with a wingspan of a 747 can carry one person, then a plane with a double that wingspan can carry 2 persons. The thing is how to combine wingspan with lift. Is there a limit to wingspan? One possible solution is unfoldable wings or a kind of sail that doesn't drag. In 100 years or less oil will be gone, and I guess people will still wanna fly.
$endgroup$
– GwenKillerby
11 hours ago
$begingroup$
@GwenKillerby : No, that's not how it works. Oil will never be completely gone. The oil reserves of the planet are not like the fuel in your car, that you drive and then at one point the car suddenly stops because fuel just ran out. As we use up the more economically extractable oil, it will become progressively more and more expensive. When it gets expensive enough, we will use less and less of it. There are many alternatives to oil, it's just that oil is so much cheaper. Once it gets expensive enough, it will be gradually replaced, first where it is easier to do so.
$endgroup$
– vsz
7 hours ago
$begingroup$
For air travel oil is much more difficult (with current technology nearly impossible) to replace, so oil will be probably used for longer, and it will last longer because other industries will use less of it. And after that, either some currently inconceivable technology will be discovered, or we will continue to use oils extracted by other means, maybe from crops.
$endgroup$
– vsz
7 hours ago
3
3
$begingroup$
Solar Impulse 2 is basically covered in solar panels of probably at least 20% efficiency. This gives it enough power to fly with just a single pilot, at about 60 mph during the day, or 30 mph on batteries at night. Even with 100% efficient panels, that's still nowhere near the power to carry a cabin full of people at much higher speeds. Modern high-speed air travel uses a ridiculous amount of energy; that's why it creates so much greenhouse gas emissions. It would be nice if solar flight were viable for airliners, but it doesn't look like it ever will be.
$endgroup$
– Peter Cordes
yesterday
$begingroup$
Solar Impulse 2 is basically covered in solar panels of probably at least 20% efficiency. This gives it enough power to fly with just a single pilot, at about 60 mph during the day, or 30 mph on batteries at night. Even with 100% efficient panels, that's still nowhere near the power to carry a cabin full of people at much higher speeds. Modern high-speed air travel uses a ridiculous amount of energy; that's why it creates so much greenhouse gas emissions. It would be nice if solar flight were viable for airliners, but it doesn't look like it ever will be.
$endgroup$
– Peter Cordes
yesterday
1
1
$begingroup$
"just solar tech isn't there yet" - that's not the problem. Even if solar panels were 100% efficient, they (and all the wiring, the motors they drive, etc.) would still weight much more than the tiny amount of fuel holding the same amount of energy. Solar panels make sense on the ground, where you have a lot of area and weight is not a big problem. Even if technology advances by ludicrous amounts to make solar powered airliners possible, the panels won't be on the plane, the solar power will be generated on the ground, and stored in batteries or fuel cells to be loaded unto the aircraft.
$endgroup$
– vsz
23 hours ago
$begingroup$
"just solar tech isn't there yet" - that's not the problem. Even if solar panels were 100% efficient, they (and all the wiring, the motors they drive, etc.) would still weight much more than the tiny amount of fuel holding the same amount of energy. Solar panels make sense on the ground, where you have a lot of area and weight is not a big problem. Even if technology advances by ludicrous amounts to make solar powered airliners possible, the panels won't be on the plane, the solar power will be generated on the ground, and stored in batteries or fuel cells to be loaded unto the aircraft.
$endgroup$
– vsz
23 hours ago
$begingroup$
It is on topic enough! And still, if a plane with a wingspan of a 747 can carry one person, then a plane with a double that wingspan can carry 2 persons. The thing is how to combine wingspan with lift. Is there a limit to wingspan? One possible solution is unfoldable wings or a kind of sail that doesn't drag. In 100 years or less oil will be gone, and I guess people will still wanna fly.
$endgroup$
– GwenKillerby
11 hours ago
$begingroup$
It is on topic enough! And still, if a plane with a wingspan of a 747 can carry one person, then a plane with a double that wingspan can carry 2 persons. The thing is how to combine wingspan with lift. Is there a limit to wingspan? One possible solution is unfoldable wings or a kind of sail that doesn't drag. In 100 years or less oil will be gone, and I guess people will still wanna fly.
$endgroup$
– GwenKillerby
11 hours ago
$begingroup$
@GwenKillerby : No, that's not how it works. Oil will never be completely gone. The oil reserves of the planet are not like the fuel in your car, that you drive and then at one point the car suddenly stops because fuel just ran out. As we use up the more economically extractable oil, it will become progressively more and more expensive. When it gets expensive enough, we will use less and less of it. There are many alternatives to oil, it's just that oil is so much cheaper. Once it gets expensive enough, it will be gradually replaced, first where it is easier to do so.
$endgroup$
– vsz
7 hours ago
$begingroup$
@GwenKillerby : No, that's not how it works. Oil will never be completely gone. The oil reserves of the planet are not like the fuel in your car, that you drive and then at one point the car suddenly stops because fuel just ran out. As we use up the more economically extractable oil, it will become progressively more and more expensive. When it gets expensive enough, we will use less and less of it. There are many alternatives to oil, it's just that oil is so much cheaper. Once it gets expensive enough, it will be gradually replaced, first where it is easier to do so.
$endgroup$
– vsz
7 hours ago
$begingroup$
For air travel oil is much more difficult (with current technology nearly impossible) to replace, so oil will be probably used for longer, and it will last longer because other industries will use less of it. And after that, either some currently inconceivable technology will be discovered, or we will continue to use oils extracted by other means, maybe from crops.
$endgroup$
– vsz
7 hours ago
$begingroup$
For air travel oil is much more difficult (with current technology nearly impossible) to replace, so oil will be probably used for longer, and it will last longer because other industries will use less of it. And after that, either some currently inconceivable technology will be discovered, or we will continue to use oils extracted by other means, maybe from crops.
$endgroup$
– vsz
7 hours ago
|
show 1 more comment
$begingroup$
I once worked for a company that made electronics for commercial aircraft (flight deck printers, Ethernet switches, digital chart recorders).
In addition to what others have mentioned on this thread, you also have to account for the fact that if a product is manufactured for aircraft in the US, it must comply AS9100 and FAR, and whatever standard the EU is using nowadays. This includes rigorous testing to ensure that, not only is the device safe, but also that the device will not interfere with any of the critical systems of the aircraft.
New contributor
$endgroup$
1
$begingroup$
How is this related to the question? Solar power is a pretty simple source of electricity to deal with compared to everything else, especially compared to a generator.
$endgroup$
– pipe
21 hours ago
add a comment |
$begingroup$
I once worked for a company that made electronics for commercial aircraft (flight deck printers, Ethernet switches, digital chart recorders).
In addition to what others have mentioned on this thread, you also have to account for the fact that if a product is manufactured for aircraft in the US, it must comply AS9100 and FAR, and whatever standard the EU is using nowadays. This includes rigorous testing to ensure that, not only is the device safe, but also that the device will not interfere with any of the critical systems of the aircraft.
New contributor
$endgroup$
1
$begingroup$
How is this related to the question? Solar power is a pretty simple source of electricity to deal with compared to everything else, especially compared to a generator.
$endgroup$
– pipe
21 hours ago
add a comment |
$begingroup$
I once worked for a company that made electronics for commercial aircraft (flight deck printers, Ethernet switches, digital chart recorders).
In addition to what others have mentioned on this thread, you also have to account for the fact that if a product is manufactured for aircraft in the US, it must comply AS9100 and FAR, and whatever standard the EU is using nowadays. This includes rigorous testing to ensure that, not only is the device safe, but also that the device will not interfere with any of the critical systems of the aircraft.
New contributor
$endgroup$
I once worked for a company that made electronics for commercial aircraft (flight deck printers, Ethernet switches, digital chart recorders).
In addition to what others have mentioned on this thread, you also have to account for the fact that if a product is manufactured for aircraft in the US, it must comply AS9100 and FAR, and whatever standard the EU is using nowadays. This includes rigorous testing to ensure that, not only is the device safe, but also that the device will not interfere with any of the critical systems of the aircraft.
New contributor
New contributor
answered yesterday
Jerry SweetonJerry Sweeton
212
212
New contributor
New contributor
1
$begingroup$
How is this related to the question? Solar power is a pretty simple source of electricity to deal with compared to everything else, especially compared to a generator.
$endgroup$
– pipe
21 hours ago
add a comment |
1
$begingroup$
How is this related to the question? Solar power is a pretty simple source of electricity to deal with compared to everything else, especially compared to a generator.
$endgroup$
– pipe
21 hours ago
1
1
$begingroup$
How is this related to the question? Solar power is a pretty simple source of electricity to deal with compared to everything else, especially compared to a generator.
$endgroup$
– pipe
21 hours ago
$begingroup$
How is this related to the question? Solar power is a pretty simple source of electricity to deal with compared to everything else, especially compared to a generator.
$endgroup$
– pipe
21 hours ago
add a comment |
$begingroup$
One consideration that makes solar aircraft less feasible is that the figure of 1kw/m2 is for sunlight striking the solar panel square on - i.e. perpendicular to the panel. Unless you're flying in the tropics at noon, an aircraft's wings won't meet that. Their insolation (the amount of power from sunlight) drops with the cosine of the angle from vertical incidence.
Regarding doubling 747 wingspan for two seats - how many passengers will settle for a 45 MPH / 39 knot / 72 kph flight speed (i.e. New York to London in 77 hours if no headwind)?
$endgroup$
add a comment |
$begingroup$
One consideration that makes solar aircraft less feasible is that the figure of 1kw/m2 is for sunlight striking the solar panel square on - i.e. perpendicular to the panel. Unless you're flying in the tropics at noon, an aircraft's wings won't meet that. Their insolation (the amount of power from sunlight) drops with the cosine of the angle from vertical incidence.
Regarding doubling 747 wingspan for two seats - how many passengers will settle for a 45 MPH / 39 knot / 72 kph flight speed (i.e. New York to London in 77 hours if no headwind)?
$endgroup$
add a comment |
$begingroup$
One consideration that makes solar aircraft less feasible is that the figure of 1kw/m2 is for sunlight striking the solar panel square on - i.e. perpendicular to the panel. Unless you're flying in the tropics at noon, an aircraft's wings won't meet that. Their insolation (the amount of power from sunlight) drops with the cosine of the angle from vertical incidence.
Regarding doubling 747 wingspan for two seats - how many passengers will settle for a 45 MPH / 39 knot / 72 kph flight speed (i.e. New York to London in 77 hours if no headwind)?
$endgroup$
One consideration that makes solar aircraft less feasible is that the figure of 1kw/m2 is for sunlight striking the solar panel square on - i.e. perpendicular to the panel. Unless you're flying in the tropics at noon, an aircraft's wings won't meet that. Their insolation (the amount of power from sunlight) drops with the cosine of the angle from vertical incidence.
Regarding doubling 747 wingspan for two seats - how many passengers will settle for a 45 MPH / 39 knot / 72 kph flight speed (i.e. New York to London in 77 hours if no headwind)?
answered 9 hours ago
Jim HornJim Horn
27913
27913
add a comment |
add a comment |
$begingroup$
I suspect that even if it were only attempting to reduce the generator load, the cost vs benefit for this kind of use would just not yield a positive return. The demand-rate is just too high.
New contributor
$endgroup$
1
$begingroup$
This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
$endgroup$
– Pondlife
4 hours ago
add a comment |
$begingroup$
I suspect that even if it were only attempting to reduce the generator load, the cost vs benefit for this kind of use would just not yield a positive return. The demand-rate is just too high.
New contributor
$endgroup$
1
$begingroup$
This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
$endgroup$
– Pondlife
4 hours ago
add a comment |
$begingroup$
I suspect that even if it were only attempting to reduce the generator load, the cost vs benefit for this kind of use would just not yield a positive return. The demand-rate is just too high.
New contributor
$endgroup$
I suspect that even if it were only attempting to reduce the generator load, the cost vs benefit for this kind of use would just not yield a positive return. The demand-rate is just too high.
New contributor
New contributor
answered 7 hours ago
user898617user898617
1
1
New contributor
New contributor
1
$begingroup$
This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
$endgroup$
– Pondlife
4 hours ago
add a comment |
1
$begingroup$
This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
$endgroup$
– Pondlife
4 hours ago
1
1
$begingroup$
This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
$endgroup$
– Pondlife
4 hours ago
$begingroup$
This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
$endgroup$
– Pondlife
4 hours ago
add a comment |
avsol is a new contributor. Be nice, and check out our Code of Conduct.
avsol is a new contributor. Be nice, and check out our Code of Conduct.
avsol is a new contributor. Be nice, and check out our Code of Conduct.
avsol is a new contributor. Be nice, and check out our Code of Conduct.
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7
$begingroup$
I'm not aware of any. And I can see several important reasons why not: solar panels are heavy, they're fragile, they require a lot of maintenance, they require a lot of wiring.
$endgroup$
– jwenting
yesterday
5
$begingroup$
@jwenting the actual solar panels aren't heavy at all. Most of the weight comes from structural reinforcements, which you don't need if you implement it into an existing structure such as the fuselage or wings. Nevertheless I don't think it would be worth it.
$endgroup$
– GittingGud
yesterday
4
$begingroup$
Solar energy is just a religion. The amount of energy gatherable per unit area is ... totally trivial. Indeed, the example of aircraft points out how utterly useless solar energy is. Solar cells are a fantastically ingenious invention for, say, calculators.
$endgroup$
– Fattie
yesterday
7
$begingroup$
As you include trail options, there have been at least two planes which have been powered completely by photovoltaic panels, Solar Impulse: en.wikipedia.org/wiki/Solar_Impulse it isn't commercial, isn't in anything like mass production, and is very slow, but they did do a round-the-world trip in the second one.
$endgroup$
– Puffafish
yesterday
29
$begingroup$
@Fattie Solar energy is perfectly workable on the ground, where getting 200W per square meter is fine.
$endgroup$
– pjc50
yesterday