How Can Technology Reduce Global Shipping's Fuel Consumption ?  

TreeHugger has a post on the post oil world, looking at energy efficient shipping, including kite sails - How Can Technology Reduce Global Shipping's Fuel Consumption?.

If we're going to start this great transition off of oil we really need to start thinking hard about how we're going to move ourselves and our goods around the globe. Part of that is thinking conceptually about it--how to change our habits and usage patterns for long-distance travel. The other part is how technology can change this. Let's deal with shipping and aviation separately. Shipping is up first.

Though it doesn't get as much coverage as other issues under the broad banner of transportation, TreeHugger has covered many ways to make shipping more environmentally friendly and reduce its fuel consumption a number of times. Here are some of those highlights:

Slowing Down Saves Tons of Fuel

As I suggested in a previous post, simply slowing down can have a great impact on the amount of fuel consumed. Known as 'super-slow-steaming' container ships traveling at speeds of 12 knots (14 mph) are going half of the top speed modern ships of this size can attain. This is in fact slower than the speeds which merchant ships sailing by wind power alone achieved over 100 years ago during the height of the golden age of sail.

The advantage is great fuel, and therefore cost and environmental, savings. A spokesperson for Maersk says that reducing speeds by 20% below the previous norm results in reducing fuel consumption by 40% per nautical mile (a nautical mile is equal to 1.15 regular miles).

When you consider that the fuel used by container ships and other modern ships is quite a bit more polluting than the fuel you use in your car--the bunker fuel that powers ships has 2,000 times the sulphur content of diesel fuel--this savings is doubly significant.

Since about 70% of global shipping's pollution occurs with 250 miles of land, global regulations to specify cleaner fuel be used could have serious implications for improving air quality and human health, in addition to reducing fuel usage and lowering global greenhouse gas emissions. In total, shipping is responsible for about 4% of total climate change emissions.

Kite Sails Reduce Fuel Usage Too

Another method to reduce fuel consumption which seems to capture the imagination, as it uses very old technology to augment modern methods, is deploying kites sails on cargo ships.

For a number of years now, tests have been underway--showing great promise--demonstrating how even on cargo ships powered by fossil fuels, if you deploy a kite sail significant savings in fuel consumption can be achieved. Even the smaller-scale kite sails used to prove the concept can substitute for 20% of the ships engines' power.

Part of that is because these kite sails are deployed far higher than even the tallest mast could go. In fact diagrams from German manufacturer SkySails show them deployed up to 200 meters above the ocean surface. ...