PHOTOVOLTAICS IN POWERING OF MARINE VESSELS

摘要

Due to increased pressure from environmental agencies and ongoing slow maritime economy, the compliance of environmental regulations stipulated in IMO conventions became hard for ship owners from implementation point of view. That's why various measures have been taken in shipbuilding to reduce emission as well as improve fuel efficiency of the vessels. Some measures are directly related to design of the ship hull such as Mewis duct, air bubble lubrication, scrubber etc. And some are related to engine and fuel used. Other than that the most appropriate alternative has been and will always be using renewable sources of energy like wind and solar, the most abundant and free one. The Impulse Power project is evident of the effectiveness of solar energy by propellingthe 31m yacht MS Turanor totally on solar power with the help of batteries. MS Turanor project was part of scientific expedition but if we want to use this system for commercial ferries or cargo ships, then there is a problem to obtain continuous output due to intermittent supply of renewable energy and high power requirement needed for completing the commercial responsibilities and service liability to society. Answer is that commercial ship can make use of renewable energy as auxiliary or part fuel source. Due to higher power and continuous power requirement it may not be viable to use huge number of Li-ion batteries which are costlier i.e. around $350/kWh. Throughout the paper an alternative to usage of expensive Li-ion battery has been discussed and supported with the necessary calculations. It mainly speaks of using solar electricity to carry out electrolysis of the abundant sea water to generate hydrogen gas and subsequently storing it safely under compressed state as a direct fuel for gas based combustion engines. As the hydrogen storage technology has reached maturity in automobile industry there won't be serious issues with safety if we customize it for ship environment. When wind energy also can be used as energy source, in this paper only solar is assumed to be only renewable energy source. The flowchart and other Paragraphs shows what will be the changed design in terms of layout and cost w.r.t Turanor design, which is taken as a model for representing the theme of this paper. There was an attempt in Germany to convert an existing oil tanker into a hydrogen producing and storing ship using vertical axis wind turbine named Hydrogen Challenger- IMO number 6724153. But nothing happened on this project after 2005 till date as recent photos also suggests. Authors of paper has given a revival to the hydrogen fuelled ship using Photovoltaic solar electricity required for production of hydrogen from electrolysis of sea water.