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>Cargo ships are also the most carbon efficient means of transporting goods. Only due to their scale, there seem to be very little 'carbon reducing' technologi

>Cargo ships are also the most carbon efficient means of transporting goods. Only due to their scale, there seem to be very little 'carbon reducing' technologies employed in the shipping trade. I don't know why some sort of modern Sail power hasn't been looked at. If you're sailing with the wind why would you not save "$40 - $80k" a day? Of wind turbines for that matter, as far as I know, most ships still derive electricity from diesel generators. Why not wind or solar?

kayoone 13y ago
i guess the explanation is quite simply: not enough power.
aunty_helen 13y ago
Ship engines produce a lot of power. Around 75MW. The size of the sails / solar / wind turbine to replace this would be...? You get the idea. As for carbon reduction, the engines already run at ~50% efficiency so there is little waste. The amount of carbon produced is the reality of pushing such a huge weight through the water.
- _mulder_ 13y ago
  Not sure why I was down-voted on this. I should have made it clearer in my post but I wasn't suggesting replacing diesel engines with Sail power, just augmenting it in the same manner as the SkySails (see response from jk4930 and markdown). I also don't see why covering the deck in solar panels, or installing some form of wind turbine, wouldn't go some way to reducing the demand from diesel power generators.
  - wmoser 13y ago
    There are a lot of people looking at fuel efficiency as well as carbon/sox/nox emmissions. For the companies running ships, the more efficient the plant is, the more money they save on fuel. About ten years ago we did a rough back of the envelope calculation in one of my engineering classes when I asked a similar question. The extra weight of the solar panels would negate any small benefit they would provide plus the cost of maintaining extra equipment. A lot modern ships run a shaft generator which uses the power from the shaft turning the propellor to turn an alternator to make electricity. When the ship slows down at the end of the trip, they go back to running smaller 'port' generators.
  - HeyLaughingBoy 13y ago
    Covering the decks in panels is going to be a non-starter for containerships where a large percentage of the cargo is carried on deck. Even for tankers with (relatively) open decks, that's not going to work to hot because of the significant amount of piping that crisscrosses the decks. In either case, I don't think you understand just how brutal the maritime environment is. A typical oceangoing ship has steel panels at main deck level dented in from the impact of the sea. I don't think solar panels are going to hold up so well. Unless you can find a way for that wind turbine to both generate electricity and work as a "sail" so it propels the ship, it is just going to add drag that is counterproductive to the problem you're trying to solve.
jk4930 13y ago
>sort of modern Sail power http://www.skysails.info/english/ http://www.skysails.info/english/
markdown 13y ago
http://en.wikipedia.org/wiki/SkySails http://en.wikipedia.org/wiki/SkySails
protomyth 13y ago
Canals were one of the original killers of sails and some of the proposals don't solve that problem (the hybrid approaches do). The modern sail will probably make a reappearance, but the current problem is the margins and capacity are such that not a lot of new generation ships are being built. I would expect that once you see car carriers adopt new technology the the rest will follow.
dredmorbius 13y ago
There's a solar-powered research ship, the Tûranor. It is entirely decked over in solar cells, and spreads "wings" to extend its surface area. The hull design is very efficient. The ship averages 5 knots. Oceangoing cargo ships maintain speeds of up to about 25 knots. In recent years, many have practiced "slow steaming", cutting their speed in half to save 30% of their fuel needs (and doubling transit times). By contrast, sailing ships averaged around 8 knots -- though one of the characteristics of sail is that your speed is much less predictable (and hence, shipping schedules). The ships were also much smaller than today's freighters, for various reasons. While it's possible that we could build larger sail-powered or hybrid ships today, they'd probably still be much smaller than fossil-fuel driven ships. Other alternatives include biofuels (most likely pelletized wood and/or cellulose). I wrote about this a few months back on G+: Is solar-powered ocean freight in your future? Wait for it .... https://plus.google.com/104092656004159577193/posts/eRygnNMpnJc https://plus.google.com/104092656004159577193/posts/eRygnNMp...
drunkenfly 13y ago
> Only due to their scale, there seem to be very little 'carbon reducing' technologies employed in the shipping trade. Not true. Take a look at what Maersk does: http://www.maersk.com/sustainability/environmentclimate/pages/co2emissions.aspx http://www.maersk.com/sustainability/environmentclimate/page...

kayoone 13y ago

i guess the explanation is quite simply: not enough power.

aunty_helen 13y ago

Ship engines produce a lot of power. Around 75MW. The size of the sails / solar / wind turbine to replace this would be...? You get the idea. As for carbon reduction, the engines already run at ~50% efficiency so there is little waste. The amount of carbon produced is the reality of pushing such a huge weight through the water.

_mulder_ 13y ago
Not sure why I was down-voted on this. I should have made it clearer in my post but I wasn't suggesting replacing diesel engines with Sail power, just augmenting it in the same manner as the SkySails (see response from jk4930 and markdown). I also don't see why covering the deck in solar panels, or installing some form of wind turbine, wouldn't go some way to reducing the demand from diesel power generators.
- wmoser 13y ago
  There are a lot of people looking at fuel efficiency as well as carbon/sox/nox emmissions. For the companies running ships, the more efficient the plant is, the more money they save on fuel. About ten years ago we did a rough back of the envelope calculation in one of my engineering classes when I asked a similar question. The extra weight of the solar panels would negate any small benefit they would provide plus the cost of maintaining extra equipment. A lot modern ships run a shaft generator which uses the power from the shaft turning the propellor to turn an alternator to make electricity. When the ship slows down at the end of the trip, they go back to running smaller 'port' generators.
- HeyLaughingBoy 13y ago
  Covering the decks in panels is going to be a non-starter for containerships where a large percentage of the cargo is carried on deck. Even for tankers with (relatively) open decks, that's not going to work to hot because of the significant amount of piping that crisscrosses the decks. In either case, I don't think you understand just how brutal the maritime environment is. A typical oceangoing ship has steel panels at main deck level dented in from the impact of the sea. I don't think solar panels are going to hold up so well. Unless you can find a way for that wind turbine to both generate electricity and work as a "sail" so it propels the ship, it is just going to add drag that is counterproductive to the problem you're trying to solve.

jk4930 13y ago

>sort of modern Sail power http://www.skysails.info/english/ http://www.skysails.info/english/

markdown 13y ago

http://en.wikipedia.org/wiki/SkySails http://en.wikipedia.org/wiki/SkySails

protomyth 13y ago

Canals were one of the original killers of sails and some of the proposals don't solve that problem (the hybrid approaches do). The modern sail will probably make a reappearance, but the current problem is the margins and capacity are such that not a lot of new generation ships are being built. I would expect that once you see car carriers adopt new technology the the rest will follow.

dredmorbius 13y ago

There's a solar-powered research ship, the Tûranor. It is entirely decked over in solar cells, and spreads "wings" to extend its surface area. The hull design is very efficient. The ship averages 5 knots. Oceangoing cargo ships maintain speeds of up to about 25 knots. In recent years, many have practiced "slow steaming", cutting their speed in half to save 30% of their fuel needs (and doubling transit times). By contrast, sailing ships averaged around 8 knots -- though one of the characteristics of sail is that your speed is much less predictable (and hence, shipping schedules). The ships were also much smaller than today's freighters, for various reasons. While it's possible that we could build larger sail-powered or hybrid ships today, they'd probably still be much smaller than fossil-fuel driven ships. Other alternatives include biofuels (most likely pelletized wood and/or cellulose). I wrote about this a few months back on G+: Is solar-powered ocean freight in your future? Wait for it .... https://plus.google.com/104092656004159577193/posts/eRygnNMpnJc https://plus.google.com/104092656004159577193/posts/eRygnNMp...

drunkenfly 13y ago

> Only due to their scale, there seem to be very little 'carbon reducing' technologies employed in the shipping trade. Not true. Take a look at what Maersk does: http://www.maersk.com/sustainability/environmentclimate/pages/co2emissions.aspx http://www.maersk.com/sustainability/environmentclimate/page...