Economic Analysis of a Brackish Water Photovoltaic-Operated (BWRO-PV) Desalination System

The photovoltaic (PV)-powered reverse-osmosis (RO) desalination system is considered one of the most promising technologies in producing fresh water from both brackish and sea water, especially for small systems located in remote areas. We analyze the economic viability of a small PV-operated RO system with a capacity of 5 m3/day used to desalinate brackish water of 4000 ppm total dissolve solids, which is proposed to be installed in a remote area of the Babylon governorate in the middle of Iraq; this area possesses excellent insolation throughout the year. Our analysis predicts very good economic and environmental benefits of using this system. The lowest cost of fresh water achieved from using this system is US $3.98/ m3, which is very reasonable compared with the water cost reported by small-sized desalination plants installed in rural areas in other parts of the world. Our analysis shows that using this small system will prevent the release annually of 8,170 kg of CO2, 20.2 kg of CO, 2.23 kg of CH, 1.52 kg of particulate matter, 16.41 kg of SO2, and 180 kg of NOx

Solar and wind opportunities for water desalination in the Arab regions

Despite the abundance of renewable energy resources in the Arab region, the use of solar thermal, solar photovoltaics, and wind is still in its technological and economic infancy. Great potential exists, but economic constraints have impeded more rapid growth for many applications. These technologies have certainly advanced technically over the last quarter century to the point where they should now be considered clean-energy alternatives to fossil fuels. For the Arab countries and many other regions of the world, potable water is becoming as critical a commodity as electricity. As renewable energy technologies advance and environmental concerns rise, these technologies are becoming more interesting partners for powering water desalination projects. We evaluate the current potential and viability of solar and wind, emphasizing the strict mandate for accurate, reliable site-specific resource data. Water desalination can be achieved through either thermal energy (using phase-change processes) or electricity (driving membrane processes), and these sources are best matched to the particular desalination technology. Desalination using solar thermal can be accomplished by multistage flash distillation, multi-effect distillation, vapor compression, freeze separation, and solar still methods. Concentrating solar power offers the best match to large-scale plants that require both high-temperature fluids and electricity. Solar and wind electricity can be effective energy sources for reverse osmosis, electrodialysis, and ultra- and nano-filtration. All these water desalination processes have special operational and high energy requirements that put additional requisites on the use of solar and wind to power these applications. We summarize the characteristics of the various desalination technologies. The effective match of solar thermal, solar photovoltaics, and wind to each of these is discussed in detail. An economic analysis is provided that incorporates energy consumption, water production levels, and environmental benefits in its model. Finally, the expected evolution of the renewable technologies over the near- to mid-term is discussed with the implications for desalination applications over these timeframes.Renewable energy Water desalination Solar thermal Solar photovoltaic Wind energy Arab region

Selecting an economically suitable and sustainable solution for a renewable energy-powered water desalination system: A rural Australian case study

Renewable energy (RE) powered reverse osmosis (RO) desalination is rapidly evolving as an attractive energy-water nexus solution that combines the sustainability of RE and the maturity of RO. The intermittent and fluctuating power of RE, the variable operation of RO systems and the social acceptance of RO, commonly perceived as an energy intensive process, are some of the challenges currently faced by scientists and decision makers. The objective of this study is to identify an energy-water system that is cost-effective, sustainable and socially accepted in a rural community of Australia. The numerical analysis is based on one year (2016) data of energy demand of the community. The size and energy demand of the RO plant is assumed based on the 2016 water demand. A modelling approach that can be readily available and simple to use by the regional energy and water utilities is developed. Out of the seven assessed energy configurations, the most cost-effective system includes a hybrid RE-RO system characterized by grid electricity, a 2.4 MW wind and a 2.8 MW distributed rooftop solar photovoltaic (RTPV) system to supply the 14 GWh and 1.2 GWh annual energy demand of the community and RO plant, respectively. A system of RTPVs distributed across the community is suggested as an option to improve the social acceptance of the RO by directly engaging the consumers in the supply of their own energy and water needs. The RO is simulated to operate as a deferrable electrical load, whose feed flow rate and operating pressure vary (within admissible limits) as a function of the renewable energy excess and the end-user's energy consumption. The proposed energy-water system aims to provide a sustainable and economical solution whilst targeting the cultural gap between community members and decision makers that has been hindering desalination projects in Australia's rural communities