Navy Ship Propulsion Technologies: Options for Reducing Oil Use -- Background for Congress

Publication Date: July 2006

Publisher: Library of Congress. Congressional Research Service

Author(s):

Research Area: Energy; Military and defense

Type:

Abstract:

General strategies for reducing the Navy's dependence on oil for its ships include reducing energy use on Navy ships; shifting to alternative hydrocarbon fuels; shifting to more reliance on nuclear propulsion; and using sail and solar power.

Reducing energy use on Navy ships. A 2001 study concluded that fitting a Navy cruiser with more energy-efficient electrical equipment could reduce the ship's fuel use by 10% to 25%. The Navy has installed fuel-saving bulbous bows and stern flaps on many of its ships. Ship fuel use could be reduced by shifting to advanced turbine designs such as an intercooled recuperated (ICR) turbine. Shifting to integrated electric-drive propulsion can reduce a ship's fuel use by 10% to 25%; some Navy ships are to use integrated electric drive. Fuel cell technology, if successfully developed, could reduce Navy ship fuel use substantially.

Alternative hydrocarbon fuels. Potential alternative hydrocarbon fuels for Navy ships include biodiesel and liquid hydrocarbon fuels made from coal using the Fischer-Tropsch (FT) process. A 2005 Naval Advisory Research (NRAC) study and a 2006 Air Force Scientific Advisory Board both discussed FT fuels.

Nuclear propulsion. Oil-fueled ship types that might be shifted to nuclear propulsion include large-deck amphibious assault ships and large surface combatants (i.e., cruisers and destroyers). A 2005 "quick look" analysis by the Naval Nuclear Propulsion Program concluded that total life-cycle costs for nuclearpowered versions of these ships would equal those of oil-fueled versions when oil reaches about $70 and $178 per barrel, respectively.

Sail and solar propulsion. Kite-assisted propulsion might be an option for reducing fuel use on Navy auxiliaries and DOD sealift ships. Two firms are now offering kite-assist systems to commercial ship operators. Solar power might offer some potential for augmenting other forms of shipboard power, perhaps particularly on Navy auxiliaries and DOD sealift ships.

Legislative activity. Section 128 of the FY2007 defense authorization bill (H.R. 5122) states that "it is the sense of Congress that the Navy should make greater use of alternative technologies, including nuclear power, as a means of vessel propulsion for its future fleet of surface combatants." The Senate report (S.Rept. 109-292 of July 25, 2006) on the FY2007 defense appropriations bill (H.R. 5631) encourages DOD to continue exploring FT fuels and requires a report on synthetic fuels. Section 214 of the conference report (H.Rept. 109-413 of April 6, 2006) on the Coast Guard and Maritime Transportation Act of 2006 (H.R. 889) requires the Coast Guard to conduct a feasibility study on using biodiesel fuel in new and existing Coast Guard vehicles and vessels. Section 130 of the conference report (H.Rept. 109-360 of December 18, 2006) on the FY2006 defense authorization act (H.R. 1815, P.L. 109-163 of January 6, 2006) requires the Navy to submit a report by November 1, 2006, on alternative propulsion methods for surface combatants and amphibious warfare ships. This report will be updated as events warrant.