رویکردهای مدیریت عرضه آب با استفاده از ایالات متحده در جزیره رودز، یونان

Desalination powered by renewable energy sources (RES) is presented as an alternative option for the water supply augmentation in the semi-arid region of the island of Rhodes. The case study was chosen as the island relies mostly on the exploitation of groundwater resources and faces serious water shortage problems in an already stressed environment. Alternatives are discussed and compared in contrast to the construction of storage dams to meet urban water needs up to the year 2040. Results may indicate that through the use of financial incentives coupled with holistic water management approaches, desalination powered by RES could be an attractive and environmentally friendly option in an effort to solve problems related to water quantity and quality in semi-arid regions with adequate renewable energy potential.

In many southern Mediterranean region water is used in an unsustainable manner. The landscape, as a whole, is ecologically fragile and seriously endangered by prevailing social and economic trends. The future of the region may be threatened by increasing coastal area stress, by expanding differences between tourist areas and between the water and soil equilibrium [11]. Most of the population is concentrated in the coastal zone,and increasing tourism causes a strong, seasonal water demand. Thus, uneven water demands in both space and time greatly increase the cost of making water accessible. Such con-ditions are exemplified very accurately in the case of the island of Rhodes.*Corresponding author.Desalination, compared to more conventional water supply related interventions, may take an advantageous position in terms of economic costs and environmental impact.Amongst the various desalination techniques, reverse osmosis (RO) has been widely used during the last years. Tech- nology advances in the field of energy recovery have managed to reduce,with the use of pressure exchangers, the specific energy consumption at 2.0 kWh/m3 for seawater desalination [2]. Low energy requirements are expected to render the particular desalination technology more compe-titive compared to other desalination techniques and conventional interventions. Under these conditions,wind powered RO desalination units could offer an effective, economic and environ- mentally friendly solution in water stressed areas where adequate wind potential exists.The island of Rhodes presents a unique challenge of a semi-arid region where shoddy water resources management and uncontrolled development have led to severe water shortages and environmental stresses. The island with an excellent wind potential seems ideal for the implementation of desalination powered by renewable energy sources (RES) to confront proliferating water resources problems. Such a policy option should be incorporated in an overall management framework in an effort to ensure the long term sustainability of the region.

Under the present conditions,surface water storage schemes are the most attractive and reliable option for the water supply development in the island of Rhodes. In this regard, desalination seems as only a complementary solution in time and space.However, desalination coupled with RES may offer a reliable enough alternative option, in the overall responses framework. Furthermore, desalination with the use of RES may be an attractive solution in cases of arid or semi-arid regions in other parts of the world that experience severe water stress conditions, It offers a reliable water supply that may also adjust to water demand fluctuation and increases,while it offers little environmental impact. The forecasted further reduction of the specific energy consumption of the reverse osmosis desalination process is also expected to lower water production costs significantly. In comparison to centralized desalination solutions, small-scale desalination units located near demand sites present a rather increased water production cost.However, with the use of appropriate financing mechanisms and the active involvement of the public sector (i.e.,joint venture schemes), the financial risk may be diminished, the profitability of the investments can be increased and the option may be fully competitive with conventional supply-side intervention.