Catálogo de publicaciones - libros

Combining renewable solar energy and desalination would generate a sustainable source of fresh water as well as energy. This combination is highly valued as it limits and reduces air pollutant emissions and green house gases generated by combustion of fossil fuels. Increase in energy demand during the first half of this century is expected to continue, which makes the cost of renewable solar energy highly competitive against fossil fuels. Desalination has been relied on to provide fresh water for large cities and countries across the world. The desalination industry continues to grow in countries in arid regions. Various aspects of solar desalination processes, solar energy, and conventional desalination are discussed. Scenarios for combination of existing units with renewable energy are evaluated. The paper also includes a brief review of a number of novel cycles for combining solar energy and desalination.

for enhancing water supplies schemes in arid lands featuring an appropriate technology for solar energy use in the irrigation field. The present paper introduces the effect of water cost production on crops yields and these are then incorporated in the financial balance. It shows that the water desalination use in irrigation could be profitable for farmers, particularly for produce of high commercial value. The solar desalination in irrigation is only worthwhile if higher crop production is adopted and assuming a high qualification of farmers. However, further technical development and lower investment costs are needed for solar desalination concepts in order to get water costs down to levels competitive to more conventional desalination methods. The work was motivated by the increasing awareness of the need

Water desalination technologies and their possible coupling with solar energy were evaluated. The topic has a remarkable interest especially for the countries located within the Southern Mediterranean belt, generally characterized by vast arid and isolated areas with practically no access to electric power from the national grid. Economic factors being one of the main barriers to the diffusion of solar devices so far, an attempt was made to estimate water production cost for two different solar desalination systems: reverse osmosis and multiple effect evaporation process driven by photovoltaic and solar thermal energy, respectively. The results, obtained for plants with a capacity varying between 500 and 5,000 m³/d, were compared to the values relevant to a conventional desalination system.

The status of process modelling systems is outlined here along with the description of a dynamic model for the analysis and prediction of multistage flash desalination units. Several different operating conditions describing the operations of a solar powered MSF unit were simulated in order to investigate the model capabilities and potential for simulating real plant operations. The model is compared to full scale plant data and to more accurate data from a laboratory scale experimental unit. Results show how an example of the new generation of modelling tools allows us to solve the complex model for many disturbances introduced to the desalination system. The model contains ordinary differential equations with sharp changes in operating conditions which have been known to cause problems to many modelling systems.

The aim of our research is to develop humidification-dehumidification desalination technique for arid regions that are suffering from shortage of potable groundwater. The specific objective of the current study was to present a methodology to predict operation of a solar powered desalination unit using the Solar Multiple Condensation Evaporation Cycle principle. The corresponding dynamic models developed from the thermal energy and mass balances represent better the real behavior of the system and can be used to investigate the effect of various parameters on the performance of the desalination unit. Suitable modular software is developed to provide adequate computational facilities for simulating, sizing, designing and optimizing this kind of desalination unit.

The south Mediterranean area is suffering from lack of drinking water. However, brackish water is abundant in these regions. Desalination of such water can be a solution to provide the needs of the local populations (less than 10 m³/day). Different solutions for brackish water desalination have been developed and many prototypes have been built and tested. Bourouni et al. (1999) developed a water desalination plant based on Aero- Evapo-Condensation Process (AECP). A prototype was built and tested in the region of Kebili in the south of Tunisia. A geothermal brackish water source was used to feed the unit. Promising results were found, since the cost of water was reduced to 1.2 USD per cubic meter of fresh water (Bourouni et al, 1999). The present study shows that the geothermal source can be replaced by solar preheated water.

The subject of this paper is to optimize the operating parameters of an actual solar desalination plant in operation and maximize its annual water production. The plant is located in Abu Dhabi, UAE, it consists of a field of evacuated tube collectors, a heat accumulator of the thermallystratified type and a multiple-effect seawater (MES) evaporator of the vertical stack type. A simulation program “SOLDES” was used to find the influence of each of the selected operating parameters on plant production. Solar radiation and other weather data for Abu Dhabi were used in the simulation runs. The results of the program were validated against the actual plant data and the agreement was found to be good. The selected plant operating parameters found to have an effect on plant water production were the heating water flow to the evaporator, the collector bypass valve open temperature and the frequency of monthly collector cleanings. The aim is to maximize monthly water production by setting these operating parameters to their optimum values. For this purpose monthly correlation equations were established by running the program at different values of each parameter and using the least square technique. The resulting monthly second-degree polynomial were optimized using the steepest ascent method.

Supported by MEDRC and the CEC, European experts in desalination, renewable energy and computational analysis in scientific collaboration with partners from Jordan and Algeria are transforming the computational systems analysis environment into a capacity for feasibility assessment analyses on de-central water and power supply, integrating renewable energy in MENA countries.

Morocco is characterised by a semi arid climate and the decrease of the available surface water has a strong impact on the renewable resources of ground water. Without additional unconventional water sources, the water deficit will keep growing, even if more dams are built in the future, since they alone will not mobilise more water by capita. The obligation to use other non conventional water resources such as desalinated water or waste water reuse and the need for a more rigorous policy of water management and planning becomes a necessity. However Morocco has a large potential of wind and solar energy sources that could be used in the sea water desalination. The paper presents the experiences of the use of renewable energy sources in desalination in Morocco and an economic analysis of wind powered desalination in the south of Morocco.

The solar potential of Bulgaria as well as opportunities for its utilisation through both thermal and photovoltaic installations is presented in this paper. The present solar power usage and ideas for energy efficiency and utilisation of renewable energy sources are shown. The fresh water resources of this country are estimated compared with the resources of other European countries and eventual future need of desalination is discussed in the work.