Clean energy airplanes questions

[AshleyAshes]

Here's a pro tip for life, kid: If you think that you've come up with a SUPER obvious way to improve something that somehow scientists and engineers the world over didn't think of; It's most likely that your comprehension of the topic is so poor that you just can't understand how bad an idea it is.

[Eduard the weeb]

 

On 11/17/2017 at 9:32 AM, AshleyAshes said:

Here's a pro tip for life, kid: If you think that you've come up with a SUPER obvious way to improve something that somehow scientists and engineers the world over didn't think of; It's most likely that your comprehension of the topic is so poor that you just can't understand how bad an idea it is.

Just wanted to know why it wasn't being used, I know something should have been wrong either to expensive or not physically possible. it happened to be 2 for wind and 1 for big airplanes.   

[Tcrumpen]

1 hour ago, Eduard the weeb said:

okay so I am not real into airplanes, but I have a question how come airplanes a major contributor pollution if you used a launch system similar to the Gerald R ford with water then wind turbines to create energy for the engines, Because the faster you got the more energy you'd produce creating a cycle, so is there a specific reason this won't work ?

 

if you know anyone into engineer, airplanes, or clean energy can you tag them to explain why this won't work or why  no-one has done it ?

If i understand you right you're saying put wind turbines on planes? Good idea in theory but other than the obvious drag problems you have a simple physics fact. One can not create more power that you use, therefore to get the power you need would require more "devices" than expected due to loss of energy due to heat, friction etc. If you want to make the point of batteries, due to the size of the aircraft to get ones realistic enough would create A LOT of extra weight which would in turn require more energy used to take off and speed up and therefore require even more turbines

 

Personally i think Planes will continue to use Kerosene till we find a form of renewable energy just as 'convenient' like if Hydrogen fuel cells were still being researched ...

[Eduard the weeb]

On 11/17/2017 at 9:49 AM, Tcrumpen said:

If i understand you right you're saying put wind turbines on planes?

Yes.

 

On 11/17/2017 at 9:49 AM, Tcrumpen said:

Good idea in theory but other than the obvious drag problems

I thought maybe you could put the turbine were the radiator is so it cools the engine and generates power AT THE SAME TIME.

 

On 11/17/2017 at 9:49 AM, Tcrumpen said:

A LOT of extra weight which would in turn require more energy used to take off and speed up and therefore require even more turbines

wouldn't it also be like SUPER DANGEROUS to put like alot of alkaline on a commercial airline because if it crashed there would be a much higher mortality rate due to it being acid ?

 

On 11/17/2017 at 9:49 AM, Tcrumpen said:

Personally i think Planes will continue to use Kerosene till we find a form of renewable energy just as 'convenient' like if Hydrogen fuel cells were still being researched ...

we'd probably a HUGE break through if we want it to happen in the next decade 2020-2040.

[Tcrumpen]

1 minute ago, Eduard the weeb said:

Yes.

 

I thought maybe you could put the turbine were the radiator is so it cools the engine and generates power AT THE SAME TIME.

 

wouldn't it also be like SUPER DANGEROUS to put like alot of alkaline on a commercial airline because if it crashed there would be a much higher mortality rate due to it being acid ?

Addressing your second point, i don't think a wind turbine could cool a engine fast enough, the acid thing is a valid point, but if they did do that they'd most likely have them in a container which doesn't react to said acid or it would have acidic fire suppressant system to neutralise said liquid

[Eduard the weeb]

17 minutes ago, Tcrumpen said:

Addressing your second point, i don't think a wind turbine could cool a engine fast enough, the acid thing is a valid point, but if they did do that they'd most likely have them in a container which doesn't react to said acid or it would have acidic fire suppressant system to neutralise said liquid

ok so that turbine wouldn't spin fast enough and The Battery would be protected with something yeah I could see that.

[Tcrumpen]

Just now, Eduard the weeb said:

ok so that turbine wouldn't spin fast enough and The Battery would be protected with something yeah I could see that.

Speed of the fan isn't so much the main problem it's the drawbacks of aircooling, it's not as efficient at cooling as liquid is (simple physics fact) why do you think cars and planes have coolant fluid and radiators rather than just gigantic fans on the bonnet. You're talking about something that would most likely get to over 100 degrees C if not cooled, in fact even when it is cooled it'll still be around 50 degrees C (for a car anyway), next time you're in a car take a glance at the thermostat on the internal dial display

[TheRandomness]

44 minutes ago, Eduard the weeb said:

Yes.

 

I thought maybe you could put the turbine were the radiator is so it cools the engine and generates power AT THE SAME TIME.

Turbine (or Turbofan or whatever) engines don't have radiators, per se. They are cooled just by running. Most of the thrust of a modern turbine engine comes from the cool air flowing around the actual turbine part (called high-bypass iirc for that setup). Also, it already generates power, how else do you think they have the electricity to power the lights and avionics and all that without recharging the internal batteries every 10 minutes?

[knightslugger]

1 hour ago, TheRandomness said:

Turbine (or Turbofan or whatever) engines don't have radiators, per se. They are cooled just by running. Most of the thrust of a modern turbine engine comes from the cool air flowing around the actual turbine part (called high-bypass iirc for that setup). Also, it already generates power, how else do you think they have the electricity to power the lights and avionics and all that without recharging the internal batteries every 10 minutes?

uhh, the APU (a turbine engine that does not produce thrust)?

[dalekphalm]

5 hours ago, Eduard the weeb said:

Yeah I assumed they guzzled some fuel, But I would like the world to stop being so uneco friendly because global warming is a thing and I think airplanes are a major part of that I believe. 

To be fair, Jet Fuel is still the most efficient way to quickly transport people and things across continents. The oceans are too big for an underwater train tunnel to be practical, and boats are REALLLYYYYYYYYYYYYYYYYY SLLLLLLLOOOOOOOWWWWWWWWWWWW.

 

There's definitely room for improvement though, in terms of fuel efficiency. Take the new Canadian made Bombardier CSeries planes - these are aimed at 100 and 150 passengers, and they're significantly more fuel efficient compared to comparable planes from Boeing, etc.

5 hours ago, knightslugger said:

oh christ, here we go.... :eyeroll:

 

*sigh* ya know what, I'm not even going to go there with a highschool student.

I mean, he misspoke a bit, by saying "Global Warming" (Since it's actually a series of cooling and warming in different ecological and geographical zones, even though global averages are indeed increasing), when instead he should have said "Anthropomorphic Climate Change".

 

But, it's pretty much not in dispute. Basically all experts in climate science, etc, agree that humans are contributing to an increase in Climate Change.

4 hours ago, AshleyAshes said:

Here's a pro tip for life, kid: If you think that you've come up with a SUPER obvious way to improve something that somehow scientists and engineers the world over didn't think of; It's most likely that your comprehension of the topic is so poor that you just can't understand how bad an idea it is.

Man you're harsh at times But it's usually an enjoyable read

[Filthyscum]

4 hours ago, knightslugger said:

uhh, the APU (a turbine engine that does not produce thrust)?

The APU is mostly used on the ground for aircon (bleed air, engine start etc.). There are some instances where the APU is used in flight; In ETOPS, prior to entering ETOPS-area APU must be started. And in emergencies, engine fail procedures calls for apu start.

 

The turbofan engines provide electrical power with its generators, pressurization with bleed air and aircon (heat exchangers, air cycle machines).

 

Fake edit: this is all for Boeing 737-300/900. Probably similar for Airbus and such.

 

Regarding fuel efficiency, planes are pretty good with that. They go really fast and really long. Fuel burn for a B737 is about 2.2 tons (metric) / hour.

[knightslugger]

1 hour ago, dalekphalm said:

increase in Climate Change.

it's funny that the term replaced global warming, and yet the word INCREASE is still being used to indicate it's getting worse when in fact, change is neither worse, nor better.

 

what exactly is an INCREASE in CHANGE anyway... 

[WMGroomAK]

7 hours ago, Eduard the weeb said:

Yeah I assumed they guzzled some fuel

Just to clarify, if it was not using fuel of some sort for combustion, it would not be using a jet engine (such as a modern turbofan) and would instead have to be propeller driven, which adds to weight, maintenance, cost, time/range of flight and decreases the maximum altitude.  These are very important factors that are glossed over.  This is not to say that airplanes are not making advancements as they are in aerodynamics (winglets) and fuel efficiency as well as fuel mixes (see below).  

 

https://blog.alaskaair.com/alaska-airlines/news/gevo-biofuel-flight/

 

http://www.boeing.com/commercial/737max/737-max-winglets/

 

How a Turbofan works: https://en.wikipedia.org/wiki/Turbofan

[LienusLateTips]

On 11/17/2017 at 7:01 AM, Implosivetech said:

Boeing isn't going to put solar panels on anything anytime soon. They tried to put an 80% import tax on the most efficient airplane.

Which went up to 220%.

[dalekphalm]

21 hours ago, knightslugger said:

it's funny that the term replaced global warming, and yet the word INCREASE is still being used to indicate it's getting worse when in fact, change is neither worse, nor better.

 

what exactly is an INCREASE in CHANGE anyway... 

The word increase is still being used because, on average, global temperatures are rising faster than they should be.

 

The reason why "Global Warming" was renamed to "Climate Change" is because every time it snowed, Climate-Skeptics would be like "SEE! IT'S NOT WARMING!" They refused to see that climate change produces spikes in localized extreme weather conditions.

 

That means that in some places, they might have unusual flash freeze blizzards. In other areas, they might have a sudden heat wave. Etc. But despite these localized events, the overall trend is still higher global averages.

 

Also the phrase "increase in change" is still a legit phrase, grammatically. It indicates an acceleration of said change. Change = temperature (Well not just temperature, but that's the most easily quantifiable part). Increase = acceleration in the rate of change.

[BlueChinchillaEatingDorito]

Airbus does have an electric plane that did traverse the English channel. However, it's going to be a long while before it's commercially viable.

 

For the time being, technologies to improve efficiency and aerodynamics is about the most we can do. Airbus is currently testing a new laminar wing that is to reduce wing friction and hence, up to a 5% reduction in CO2.

Spoiler

 

[Dash Lambda]

I've often wondered how viable it would be to use hydrogen fuel for airplanes. I mean, it's much cleaner than jet fuel, I imagine comparable in terms of energy, it's compressible (for storage), and we can readily produce it from water.

That is of course not meaning a hydrogen fuel cell, that's not even close to the only way to use it. Hydrogen internal-combustion engines are a thing. Of course hydrogen is way more volatile than jet fuel (and gas, and diesel, and lots of other things), but I wonder how much you can get around that with shielding and separating tanks.

 

As for electric aircraft, we're a little ways away. Electric motors are actually pretty damn efficient and powerful, but energy storage isn't quite there yet. Lithium batteries just aren't viable in terms of capacity and weight.

Fuel cells might work in small aircraft, but really we need good clean power plants before this stuff is viable. Maybe fusion will do that, but that's very much in the future.

 

As for the original question, while it is true that you couldn't just have a perpetual motion machine, I imagine you could improve efficiency somewhat by adding generator turbines -But not enough to justify it. Solar panels are much more effective, and in fact I think the first electric aircraft to circumnavigate (If I recall correctly) had a solar array on top.

[knightslugger]

5 minutes ago, Dash Lambda said:

how viable it would be to use hydrogen fuel for airplanes.

Ever hear of the Hindenburg?

[Dash Lambda]

5 minutes ago, knightslugger said:

Ever hear of the Hindenburg?

Yes.

That's like saying "Ever heard of the Titanic?" to someone talking about building particularly large boats.

[knightslugger]

4 minutes ago, Dash Lambda said:

Yes.

That's like saying "Ever heard of the Titanic?" to someone talking about building particularly large boats.

okay, so do you see the [problem?

[TheRandomness]

On 17/11/2017 at 6:04 PM, knightslugger said:

uhh, the APU (a turbine engine that does not produce thrust)?

That is not run during flight.

[vanished]

11 minutes ago, knightslugger said:

okay, so do you see the [problem?

Are you suggesting that there's never been a ship as large since, or that any of them are doomed to be unsafe?  Because neither of those things are true.

[Dash Lambda]

12 minutes ago, knightslugger said:

Okay, so do you see the problem?

What do you mean by that? I addressed the fact that hydrogen was more volatile than traditional fuel in my original post.

And the Hindenburg was a 250m long cotton balloon, originally designed to use helium, pumped up with 200,000,000 liters of hydrogen. There really isn't much of a valid comparison with modern technology.

[Zodiark1593]

43 minutes ago, Dash Lambda said:

I've often wondered how viable it would be to use hydrogen fuel for airplanes. I mean, it's much cleaner than jet fuel, I imagine comparable in terms of energy, it's compressible (for storage), and we can readily produce it from water.

That is of course not meaning a hydrogen fuel cell, that's not even close to the only way to use it. Hydrogen internal-combustion engines are a thing. Of course hydrogen is way more volatile than jet fuel (and gas, and diesel, and lots of other things), but I wonder how much you can get around that with shielding and separating tanks.

 

As for electric aircraft, we're a little ways away. Electric motors are actually pretty damn efficient and powerful, but energy storage isn't quite there yet. Lithium batteries just aren't viable in terms of capacity and weight.

Fuel cells might work in small aircraft, but really we need good clean power plants before this stuff is viable. Maybe fusion will do that, but that's very much in the future.

 

As for the original question, while it is true that you couldn't just have a perpetual motion machine, I imagine you could improve efficiency somewhat by adding generator turbines -But not enough to justify it. Solar panels are much more effective, and in fact I think the first electric aircraft to circumnavigate (If I recall correctly) had a solar array on top.

A generator turbine would only be a viable choice if it contributes to negligible drag at cruising speeds (and altitude). Assuming you can bypass this hurdle, they could be a viable air brake during descent that can generate electricity.

[BuckGup]

On 11/17/2017 at 8:16 AM, Dreaper said:

Could solar panels on planes work?

We are taking about jet fuel. It's crazy refined but no to the point of rocket fuel. Still solar will never have the energy output needed in anyones life time for the next 90 years