Abstract
The fresh water has become a challenging problem for many countries, especially in arid and semi-arid regions, with population growth and a shortage of water resources. This problem let the desalination plants become the main source of potable, industry, and irrigation. Libya is one of these countries. In this paper first and second thermodynamics laws were used to investigate the exergy and economic analysis of proposed desalination plant in Waddan City in Libya to provide desalination technique to be used in this area, as the source of brackish water is available. The model and simulation results for single pass SRO with PX powered ORC using solar energy has been carried out in this paper, IPSEpro software was used. Libyan environmental data for brackish water at Waddan City were used in this model, to produce about 8208m3/day for the local community. a comparison between electricity from grid and ORC powered by solar energy. The results showed that using ORC better than using electricity from grid. Keywords: Exergy efficiency, economic analysis, RO, ORC and solar energy