5 ms·

You're comparing things that aren't comparable. Of course single occupancy cars are inefficient, but that shouldn't obscure the fact that long distance transpor

You're comparing things that aren't comparable. Of course single occupancy cars are inefficient, but that shouldn't obscure the fact that long distance transportation is a major source of emissions that should be severely limited. The fact that the industry is efficiency focused is also irrelevant at best, because they are high emitters in spite of it.

briandear 8y ago
Ok so stop buying things and do your part. The globe isn’t warming as much as you think.
shoo 8y ago
it seems like people in countries like mine (rich, western) find it very easy to blame the supply side of the equation rather than the demand side of the equation -- e.g. companies are to blame for wrecking the environment because they ship stuff in planes to save money / save time. but the general public are also to blame as the source of demand. what might make a huge positive difference for the environment would be rolling out policies to help reduce population growth (or the absolute population count) of people such as myself with relatively affluent polluting lifestyles, but we might have to wait until there is mass suffering right here right now due to environment reasons across many countries with political power before there is substantial change.
- mojomark 8y ago
  >>...the general public are also to blame as the source of demand. Yes, but companies have absolute control over what mode of transport is used to do shipping, not consumers. Demand is good for the economy, so you do not want to quash it. You DO want companies to satisfy demand responsibly. In the maritime trade industry, we can absolutely fuel global shipping 100% on GHG emission-free renewables using H2 fuel cells. The tide is starting to turn, albeit a little too slow for my taste. Granted, the challenge is exponentially harder for extreme high power density kWh consumers like aircraft. Ships are very high kWh consumers, but don't have the power density of aircraft, so much lower density/higher weight fuels and engines can be employed that makes the problem significantly easier to solve. ...Also, Thanos, please count me among one of your childless population growth inhibitors. I don't dissagree with you there.
  - nradov 8y ago
    Carrying large tanks of compressed hydrogen on merchant ships isn't safe or practical. Sustainable carbon-neutral liquid bio-fuels are a more likely long term solution. Those can be used with minimal changes to our existing transportation systems once the production cost comes down.
    - jessaustin 8y ago
      We have to be careful with massive new demand for biofuels. Even small changes to e.g. ethanol policy have caused food shortages (well, higher commodity food prices, but at some level these are equivalent) in the past.
    - mojomark 8y ago
      H2 fuel is absolutely practical and we're integrating it into designs as we speak. However, we are using Cryogenic Liquid H2 (conforming to IMO IGC(1)) which msy be stored at atmospheric pressure, not compressed gas, although additional regulations for shipboard H2 storage are emerging as the popularity grows(2). It's not dissimilar from carrying LNG. Biofuels still release GHG's (2), not just carbon), and it's arguable how much is recovered. The Nitrogen released still contribute to acid rain. Why go through this messy hassle and guessing game when we already have a perfectly environmentally clean cycle of breaking down H20 into H and O2 via renewables, then recombining the H with free O2 in fuel cells to produce e- and exhaust only water? 1. International Code for Construction and Equipment of Ships Carrying Liquefied Gases (http://www.imo.org/en/OurWork/Environment/PollutionPrevention/ChemicalPollution/Pages/IGCCode.aspx http://www.imo.org/en/OurWork/Environment/PollutionPreventio...) 2. http://gcaptain.com/classnk-releases-guidelines-liquefied-hydrogen-carriers/ http://gcaptain.com/classnk-releases-guidelines-liquefied-hy... 3. http://biofuel.org.uk/greenhouse-gas-emissions.html http://biofuel.org.uk/greenhouse-gas-emissions.html
      - nradov 8y ago
        Breaking down water into hydrogen and then processing it through a fuel cell is very energy inefficient. Unless we have some breakthrough efficiency improvements, hydrogen fuel will probably never be economically viable on a large scale.
czep 8y ago
Airplanes account for 5% of global emissions. Ground transport, 40%. Presently, the low hanging fruit is ground not only because of its much larger share of emissions, but also because transitioning to renewables is easier (at least today) for road than air vehicles. Noone is going to "severely limit" air transport due to its emissions. Doubling the cost of oil, maybe, but not emissions.
- jandrese 8y ago
  Ironically a heavy push to electrified cars would reduce demand for gasoline, potentially dropping the price of oil and saving money for airlines and reducing ticket prices. The final result would be increased air travel and CO2 emissions from air travel. Overall still a win for the environment, but not as much of one as people would want.
- joelthelion 8y ago
  > Noone is going to "severely limit" air transport due to its emissions If no one does it (and many other radical changes), we will have 4+°C warming and a major global catastrophe. I'm not optimistic, but that's what should be done.

briandear 8y ago

Ok so stop buying things and do your part. The globe isn’t warming as much as you think.

shoo 8y ago

it seems like people in countries like mine (rich, western) find it very easy to blame the supply side of the equation rather than the demand side of the equation -- e.g. companies are to blame for wrecking the environment because they ship stuff in planes to save money / save time. but the general public are also to blame as the source of demand. what might make a huge positive difference for the environment would be rolling out policies to help reduce population growth (or the absolute population count) of people such as myself with relatively affluent polluting lifestyles, but we might have to wait until there is mass suffering right here right now due to environment reasons across many countries with political power before there is substantial change.

mojomark 8y ago
>>...the general public are also to blame as the source of demand. Yes, but companies have absolute control over what mode of transport is used to do shipping, not consumers. Demand is good for the economy, so you do not want to quash it. You DO want companies to satisfy demand responsibly. In the maritime trade industry, we can absolutely fuel global shipping 100% on GHG emission-free renewables using H2 fuel cells. The tide is starting to turn, albeit a little too slow for my taste. Granted, the challenge is exponentially harder for extreme high power density kWh consumers like aircraft. Ships are very high kWh consumers, but don't have the power density of aircraft, so much lower density/higher weight fuels and engines can be employed that makes the problem significantly easier to solve. ...Also, Thanos, please count me among one of your childless population growth inhibitors. I don't dissagree with you there.
- nradov 8y ago
  Carrying large tanks of compressed hydrogen on merchant ships isn't safe or practical. Sustainable carbon-neutral liquid bio-fuels are a more likely long term solution. Those can be used with minimal changes to our existing transportation systems once the production cost comes down.
  - jessaustin 8y ago
    We have to be careful with massive new demand for biofuels. Even small changes to e.g. ethanol policy have caused food shortages (well, higher commodity food prices, but at some level these are equivalent) in the past.
  - mojomark 8y ago
    H2 fuel is absolutely practical and we're integrating it into designs as we speak. However, we are using Cryogenic Liquid H2 (conforming to IMO IGC(1)) which msy be stored at atmospheric pressure, not compressed gas, although additional regulations for shipboard H2 storage are emerging as the popularity grows(2). It's not dissimilar from carrying LNG. Biofuels still release GHG's (2), not just carbon), and it's arguable how much is recovered. The Nitrogen released still contribute to acid rain. Why go through this messy hassle and guessing game when we already have a perfectly environmentally clean cycle of breaking down H20 into H and O2 via renewables, then recombining the H with free O2 in fuel cells to produce e- and exhaust only water? 1. International Code for Construction and Equipment of Ships Carrying Liquefied Gases (http://www.imo.org/en/OurWork/Environment/PollutionPrevention/ChemicalPollution/Pages/IGCCode.aspx http://www.imo.org/en/OurWork/Environment/PollutionPreventio...) 2. http://gcaptain.com/classnk-releases-guidelines-liquefied-hydrogen-carriers/ http://gcaptain.com/classnk-releases-guidelines-liquefied-hy... 3. http://biofuel.org.uk/greenhouse-gas-emissions.html http://biofuel.org.uk/greenhouse-gas-emissions.html
    - nradov 8y ago
      Breaking down water into hydrogen and then processing it through a fuel cell is very energy inefficient. Unless we have some breakthrough efficiency improvements, hydrogen fuel will probably never be economically viable on a large scale.

czep 8y ago

Airplanes account for 5% of global emissions. Ground transport, 40%. Presently, the low hanging fruit is ground not only because of its much larger share of emissions, but also because transitioning to renewables is easier (at least today) for road than air vehicles. Noone is going to "severely limit" air transport due to its emissions. Doubling the cost of oil, maybe, but not emissions.

jandrese 8y ago
Ironically a heavy push to electrified cars would reduce demand for gasoline, potentially dropping the price of oil and saving money for airlines and reducing ticket prices. The final result would be increased air travel and CO2 emissions from air travel. Overall still a win for the environment, but not as much of one as people would want.
joelthelion 8y ago
> Noone is going to "severely limit" air transport due to its emissions If no one does it (and many other radical changes), we will have 4+°C warming and a major global catastrophe. I'm not optimistic, but that's what should be done.