The analysis of possible methods of providing fresh water for sailing vessels based on the example of s/v Dar Młodzieży

In this paper the possibilities of providing fresh water for sailing vessels based on the example of s/v Dar Modziey are presented. Different methods of obtaining fresh water such as rainwater harvesting, replenishing water tanks at harbours, collecting condensed water from air conditioning systems or producing fresh water from seawater by means of desalination equipment were considered. Vacuum vaporizers (heated by fresh water used as a cooling medium of the main propulsion engines) and osmotic desalinators (using the phenomenon of reverse osmosis) were being taken under consideration. Special focus was put on the quality of water obtained; comparing the methods mentioned and pursuing the best solution both in technical and economic terms. The choice of desalinators was preceded by the analysis of quantity and configuration of pumps and membranes that will guarantee optimum performance. Selection of the manufacturer was determined by costs of purchase, costs of operation and the availability of spare parts and consumables. The osmotic desalinator ended up as the final choice of fresh water producing device on s/v Dar Modziey. Excessive water consumption can be satisfied by replenishing supplies at ports. The paper is concluded with comments and suggestions that can be adapted by a ship owner as a solution for the problem of supplying vessels with fresh water.