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Aviation industry tries to go green

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Re: Aviation industry tries to go green

#51

Post by magicalhippo »

upofadown wrote: post #34
animalnewbie wrote: post #30

Earlier quoted context omitted.

It does exactly. Thank you. This is 4 times that of a singly occupied car. Probably more effort should go towards car pooling. And maybe electric scooters.

That's only a meaningful comparison if you drive across oceans to different continents. People tend to fly much much longer distances than they drive. Supposedly a single long over ocean flight costs something the same as a whole year of driving in terms of carbon emission.

To put it in perspective, I live in Norway, and I live in the city where I work. Driving to and from work each day for a year would be roughly the same distance[1] as a single direct flight to and from New York.

Of course an ICE car doesn't get the same milage as that aircraft, but it's just a factor of 2-3 off. And then there's the difference in emissions and between a jet engine with its jet fuel vs the ICE car. For someone like me, even if I was driving to work, that single vacation would be a significant contribution to my travel CO2 footprint.

[1]: https://www.airmilescalculator.com/distance/osl-to-jfk/

Re: Aviation industry tries to go green

#52

Post by Symbiote »

WalterBright wrote: post #37
imsofuture wrote: post #29

Earlier quoted context omitted.

I know that for piston engine aircraft, it is critical that the engine be properly warmed up before takeoff. Otherwise, the engine would likely stall shortly after liftoff, leading inevitably to a crash. This is a common cause of accidents. This is not true. Engine start to takeoff is usually at least a few minutes, but there is no critical temperature factor for the engine (barring extreme heat or cold). It's a lot…

My source is my father, who flew 23 different types of aircraft, single engine, multi engine, piston and jet. He spent some years as a flight instructor, and a crash investigator for the Air Force. He said not properly warming up the piston engine meant that there was cold oil still in the reservoir, and sucking that into the engine would cause it to stall, usually right after takeoff, causing many accidents. I've re…

I remember this (reported in mainstream news as well as this eco-blog), with pollution at London Heathrow reduced by taxiing with only one engine running.

I don't know if it was implemented generally.

https://www.treehugger.com/aviation/airports-can-cut-noise-p...

Re: Aviation industry tries to go green

#53

Post by benhurmarcel »

animalnewbie wrote: post #30
jcampbell1 wrote: post #27

Earlier quoted context omitted.

Airlines get about 40-60 passenger miles per gallon. Not sure if that answers your question.

It does exactly. Thank you. This is 4 times that of a singly occupied car. Probably more effort should go towards car pooling. And maybe electric scooters.

> This is 4 times that of a singly occupied car.

How do you get that? A normal modern car does 5.5 L/100km (~40 mpg) nowadays.

Re: Aviation industry tries to go green

#54

Post by benhurmarcel »

cgrealy wrote: post #18
moltar wrote: post #9

Earlier quoted context omitted.

World's first fully electric commercial aircraft takes flight in Canada https://www.theguardian.com/world/2019/dec/11/worlds-first-f... Of course far from intercontinental jet, but it’s a start :)

Did you watch the video I posted? It specifically talks about converting a small aircraft and says you could get "about 20 minutes". Building an actually useful commercial plane (i.e. something along the lines of 737 or A320) is an order of magnitude more difficult, in fact, basically impossible with current battery technology.

For electric airliners, most promising research centers on hydrogen fuel cells, not batteries. It brings a lot of issues (mainly volume and cooling), but still it's being seriously considered.

Re: Aviation industry tries to go green

#55

Post by tobylane »

ses1984 wrote: post #38
jcampbell1 wrote: post #27

Earlier quoted context omitted.

Airlines get about 40-60 passenger miles per gallon. Not sure if that answers your question.

I was under the impression that metrics like this are too simple to tell the full story. Burning a gallon of ICE fuel at sea level has a different environmental impact than burning a gallon of jet fuel thousands of meters in the air. I think it might be better to compare in terms of "passenger mile per unit of greenhouse effect" but then how do you even get to agreement on how to measure the greenhouse effect...

The carbon equivalent output of cleanly burning one gallon of gas/petrol at sea level? A bit like https://en.wikipedia.org/wiki/Gasoline_gallon_equivalent

Re: Aviation industry tries to go green

#56

Post by jamil7 »

Is a large part of this also a political issue? with subsidies and tax breaks on fuel the aviation industry is not really incentivised to innovate and cosumers are not incentivised to seek other modes of transport since flying is often the cheapest and fastest.

Re: Aviation industry tries to go green

#57

Post by stingraycharles »

tonyedgecombe wrote: post #48

Aviation looks like the industry least likely to go green to me. I doubt electric planes are ever going to be viable for anything other than a short hop which would be better done by train. Synthetic fuels sounds interesting until you look at how much fuel they consume. The trend is quite obviously in the wrong direction: https://www.statista.com/statistics/655057/fuel-consumption-... It's often quoted as 2% of globa…

I think it’s important to look at this from a different angle: sure their requirements are high, and they may not be able to go completely green in a short timeframe, but should we therefor not even attempt it?

It’s not difficult to imagine a hybrid system at some point in the near future, and/or other ways of reducing the carbon footprint. Focus on those positive things, rather than “this will never be completely green, so why bother?”

Re: Aviation industry tries to go green

#58

Post by jeromegv »

tonyedgecombe wrote: post #48

Aviation looks like the industry least likely to go green to me. I doubt electric planes are ever going to be viable for anything other than a short hop which would be better done by train. Synthetic fuels sounds interesting until you look at how much fuel they consume. The trend is quite obviously in the wrong direction: https://www.statista.com/statistics/655057/fuel-consumption-... It's often quoted as 2% of globa…

Only solution is to have some type of carbon tax on local travels and use it to reinvest in a train network. A lot of the air flights in North America would be better served by high speed trains. We won’t have an alternative to long distance flights, but there is one for shorter flights.

Re: Aviation industry tries to go green

#60

Post by tonyedgecombe »

stingraycharles wrote: post #57
tonyedgecombe wrote: post #48

Aviation looks like the industry least likely to go green to me. I doubt electric planes are ever going to be viable for anything other than a short hop which would be better done by train. Synthetic fuels sounds interesting until you look at how much fuel they consume. The trend is quite obviously in the wrong direction: https://www.statista.com/statistics/655057/fuel-consumption-... It's often quoted as 2% of globa…

I think it’s important to look at this from a different angle: sure their requirements are high, and they may not be able to go completely green in a short timeframe, but should we therefor not even attempt it? It’s not difficult to imagine a hybrid system at some point in the near future, and/or other ways of reducing the carbon footprint. Focus on those positive things, rather than “this will never be completely gr…

“this will never be completely green, so why bother?”

You are putting words in my mouth, I never said that.

The industry has been reducing emissions per mile pretty much since it was founded. Looking at that graph I posted it is having the opposite effect to what we want. Jevon's paradox and all that.

My personal solution was to stop flying, I haven't got on a plane for 19 years. I'm not sure that is palatable to most people here though, it certainly isn't to the airline industry.

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