|
The ship requires energy for propulsion and for on-board heating and cargo operations. It is necessary to generate electricity on board supplied by the main propulsion engines. Also, the heating and cargo operations on board are supplied by the boiler. While the main engines are shut down at the berth, the auxiliary engines and boilers are kept running to support onboard operations. For example, an ocean-going cruise ship could burn approximately 220 MWh (fuel) every 10 hours to meet the energy demand on board. As a comparison, the main (propulsion) engines of the same ship could use 220 MWh (fuel) to sail approximately 100 km at sea. The ships used heavy fuel oil (HFO) and marine gas/diesel propulsion engines (MGO/MDO) and on-board operations that emit, among others, greenhouse gases (GHGs) that contribute to global climate change. The energy currently supplied to ships by HFO/MGO/MDO can be replaced in the future by energy stored in batteries or by energy from synthetic fuels such as liquid hydrogen or ammonia that do not generate GES emissions. In addition, diesel or marine methane can also be synthetically produced by capturing and regenerating H2 and CO2 and used as a replacement for fossil HFO/MGO/MDO. Taking into account the technical characteristics, including the conversion inefficiencies of each type of technology, the implications on primary energy production will be different, that is, an increase in efficiency is recorded with each type.
|
