Renewable primary power source for desalination plants in coastal zones.Analysis and economical assessment in a disparching regulatory policy

Climate change with its fluctuations of temperature and meteorological precipitations together with demographic pressure has made water disposal for human consumption a major problem. In coastal maritime areas desalination plant technology is one of the proposed solutions to face water needs, its economic convenience has to be evaluated when a renewable source is used as an alternative primary energy. The economical evaluation depends upon the regulatory policy governing electrical prices in the plant-hosting country. Here the focus is on the regulatory policy, on the power selling option within the deregulated market, on renewables and on the standards and rules applied in Italy, as solar and wind sources are elected as primary energy to hybrid desalination systems. A case study concerning the Asinara Island, an area with special environmental constraints, is developed. The paper analyses the desalination plant design and operation for a respectful use of the soil and a wide seasonal swing of water demand. Governance actions aiming at a more responsible use of water resources are taken into account. The recalled model is applied to analyze the integrated system performance to search for the optimum solution. After statistical water demand and renewable energy sources (wind, solar) availability are obtained, the features of the system are calculated.