Shipping activities are major contributors to air pollution at sea which mostly occur as a result of
ships exhaust emissions. Stringent emission limits imposed by the International Maritime Organization
(IMO) and concerns about the depletion of fossil fuel reserves have hastened the need to
find new alternative fuels for marine engines. This study investigates the effects of a low proportion
of palm fatty acid methyl ester (PFAME) biodiesel which is renewable and environmentally friendly
fuel on marine diesel engines performance and combustion characteristics. The results revealed
the use of PFAME biodiesel blends reduces the harmful gases emission CO2 and NOX emission
up to 9.1% and 7.8%, respectively. Oxygen elements in biodiesel has contributed to increase peak
in-cylinder pressure and heat release rate up to 2.7% and 4.5% respectively, thereby promoting
complete combustion. Besides that, the brake specific fuel consumption raised by 18.8% at higher
engine speeds. This finding suggests that a low concentration of PFAME biodiesel is suitable for
use in marine diesel engines without engine modification, thereby providing a positive benefit to the
environment in terms of lower emission of toxic gases.