A comprehensive economic evaluation of integrated desalination systems, using fossil fuelled and nuclear energies, and including their environmental costs

摘要

Seawater desalination is now widely accepted as an attractive alternative source ofrnfreshwater for domestic and industrial uses. Despite the considerable progress made in the relevantrntechnologies desalination, however, remains an energy intensive process in which the energy cost isrnthe paramount factor.rnThis study is a first of a kind in that we have integrated the environmental costs into the power andrndesalination costs. The study has focused on the seawater desalination cost evaluation of the followingrnsystems. It is supposed that they will be operating in the co-generation mode (simultaneous productionrnof electrical power and desalted water) in 2015:rn1.Fossil fuelled based systems such as the coal and oil fired plants and the gas turbine combinedrncycle plant, coupled to MED, and ROrn2. Pressurized water reactors such as the PWR-900 and the AP-600, coupled to MED, and RO.rn3. High temperature reactors such as the GT-MHR, the PBMR, coupled to MED, with thernutilization of virtually free waste-heat provided by these reactors.rnThe study is made in real site-specific conditions of a site in Southern Europe.rnSensitivity studies for different parameters such as the fossil fuel prices, interest and discount rates,rnpower costs etc., have also been undertaken.rnThe results obtained are then used to evaluate the financial interest of selected integrated desalinationrnsystems in terms of a detailed cash flow analysis, providing the Net Present Values, Pay Back Periodsrnand the Internal Rate of Returns.rnAnalysis of the results shows that among the fossil fuelled systems the power and desalination costs byrncirculating fluidized bed coal fired plant would be the lowest with current coal prices. Those by oilrnfired plants would be highest. In all cases, integrated nuclear energy systems would lead tornconsiderably lower power and water costs than the corresponding coal based systems.rnWhen external costs for different energies are internalised in power and water costs, the relative costrndifferences are considerably increased in favour of the nuclear systems. Financial analysis furtherrnconfirms these conclusions.