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

On the selective deposition of tin and tin oxide on various glasses using a high power diode laser

The deposition of SnO2 using a 120 W high power diode laser (HPDL) on both fused silica and soda-lime-silica glass has been successfully demonstrated. Deposition on both glass substrates was carried out with laser power densities of 650-1600 W cm-2 and at rates of 420-1550 mm min-1. The thickness of the deposited layers was typically around 250 m. The maximum theoretical coverage rate that it may be possible to achieve using the HPDL was calculated as being 3.72 m2 h-1. Owing to the wettability characteristics of Sn, it proved impossible to deposit the metal on either glass substrate. Evidence of solidified microstructures was observed, with the microstructures differing considerably across the same deposited track. These differences were attributed to variations in the solidification rate, R, and the thermal gradient, G. Adhesion of the SnO2 with the soda-lime-silica glass was found to be due to mechanical bonding. The adhesion of the SnO2 with the fused silica was seen to the result of a chemical bond arising from an interface region between the SnO2 and the fused silica glass substrate. This interface region was found to be comprised of mainly Si and rich with Sn3O4

Photovoltaics: A review of cell and module technologies

This review centers on the status, and future directions of the cell and module technologies, with emphasis on the research and development aspects. The framework is established with a consideration of the historical parameters of photovoltaics and each particular technology approach. The problems and strengths of the single-crystal, polycrystalline, and amorphous technologies are discussed, compared, and assessed. Single- and multiple junction or tandem cell configurations are evaluated for performance, processing, and engineering criteria. Thin-film technologies are highlighted as emerging, low-cost options for terrestrial applications and markets. Discussions focus on the fundamental building block for the photovoltaic system, the solar cell, but important module developments and issues are cited. Future research and technology directions are examined, including issues that are considered important for the development of the specific materials, cell, and module approaches. Novel technologies and new research areas are surveyed as potential photovoltaic options of the future.

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