For more than 15 years, the National Oceanographic and Atmospheric Administration (NOAA) has been researching and using B100 biodiesel in a number of its own fleets as part of thier Green Ships Initiative. NOAA’s research has concluded that B100 biodiesel reduces unburned hydrocarbons by almost 80 percent in comparison with fossil diesel, assuming 100-percent recycled oil. Research has shown that restaurants in the United States produce only about 300 million gallons of waste cooking oil annually, and the commercial U.S. marine industry alone consumed 2.25 billion gallons of diesel in 2012.
This shortfall limits the universal adoption of biodiesel. Meanwhile, commercially made and ASTM-certified biodiesel is no longer as available from marine fueling stations as it was earlier in the 2000s. In a further effort to decrease emissions and operating costs, international marine emission regulations have caused commercial shipping companies to shift to the use of liquified natural gas (LNG), reducing the use of dirty, heavy bunker and diesel.
In thinking about a possible endgame for clean marine propulsion, in the past several years NOAA has been modifying marine diesels to run on either B100 or compressed natural gas. They are looking at evolving this program into dual-fuel B100 and hydrogen diesels that could actually clean the seawater upon which they float, at least marginally. This could be the holy grail of a clean marine propulsion strategy that retains the necessary long range and continuing use of existing machinery.In concert with the Navy, Coast Guard, and other federal agencies, NOAA has conducted major testing and trials that have documented 20 to 40 percent lower operating costs, much longer injector lifetimes, overall better performance, extended engine life, substantially lower emissions of nitrous oxide (NOx) and an 85 percent reduction of the carcinogens that are in diesel No. 2 exhaust, which the EPA and World Health Organization last year declared to be as dangerous as second-hand smoke.