|(Credit: University of Tokyo)|
The gigantic sails telescope so can be automatically controlled to provide maximum assistance according to wind conditions.
Further improvements in fuel consumption could of course be made by slowing down. Already many ships are sailing at reduced speeds, slowing from 25 knots to 20 knots. Maersk, the world's largest shipping line, has slowed all the way down to 12 knots - less than the speed of pure sailing ships in 19th century. The has resulted in 30% less fuel use and greenhouse gas emissions and saves them tens of millions of dollars per year in fuel costs. So imagine combining the two strategies.
While a return to pure sail will come in the long term, an advantage to the University of Tokyo system is that it can be retrofitted to existing ships. They are hoping to start seeing them in use by 2016.
Irony of irony if we start shipping fossil fuels using sail powered ships.