Return to sail power merchantmen?
Commercial shipping might once again return to the Age of Sail if a study by a Danish naval architect proves the plan to be cost-effective. The Windship Project, being conducted by the Copenhagen firm Knud E. Hansen (KEH) and supported by a grant from the Danish government, involves the possibility of having auxiliary sails rigged on large, ocean-going bulk carriers.
According to KEH, bulk carriers, which, unlike containerships, transport goods like grain and rice that are less time sensitive, would benefit from auxiliary sails by delivering significant fuel savings.The new bulk carriers would be approximately 650 feet in overall length and be fitted with up to six masts of no more than 200 feet in height, which would carry 33,000-square feet of sail.
These dimensions would allow for transit through the Panama Canal.The masts, offset to the vessel’s port side to permit access to cargo hatches on deck, would be rigged with fully battened, junk-style sails operated from the bridge by an automated hydraulic trimming system. With sails and engine working together, average speed of the future sailing ships would be around 11 knots.Besides fuel savings, wind propulsion would reduce polluting emissions. “Operating a vessel like this would be very valuable if a company would like to have a green image,” said Niels Prip, managing director of the Windship Project for KEH.
Divided into three planning phases, the project has received preliminary approval by the Danish Ministry of Energy, according to Prip. “In phase two we will look at advanced material for rigging development, particularly high-tensile steel and carbon fiber,” Prip said. The final phase of the project, expected to last for another two years, will examine various types of hull construction.
The last experiment in commercial sail, conducted by the Japanese in 1984, resulted in construction of a small-tonnage oil tanker fitted with an auxiliary sail rig. The vessel’s owners had hoped for a 10% cut in fuel costs but realized up to 50% in savings, according to Paul Priebe’s book Modern Commercial Sailing Ship Fundamentals (Cornell Maritime Press, 1986).
The largest modern auxiliary-sail vessel, also built by the Japanese in the early 80s, was a 26,000-ton bulk carrier that sailed between the Pacific Northwest and Japan in the lumber trade. This vessel achieved 20% in fuel savings, or approximately $280,000 annually. As oil prices dropped in the mid-1980s, however, commercial sail was again abandoned.
If final plans for the Windship Project are approved, construction of a small wind-assisted prototype vessel would begin sometime in the first decade of the next century. “The plan would be to build a smaller version, like 5,000 tons or so, and then eventually build one of 50,000 tons,” Prip said.