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Solar desalination plant harnesses energy to produce freshwater
In the 2008 James Bond film “Quantum of Solace,” Bond takes on wealthy businessman Dominic Greene, whose environmentalism is only a facade for the real aim of his sinister ambitions: to dominate the economy of Bolivia by seizing control of its water supply. “This is the world’s most precious resource,” Greene said. “We must control as much of it as we can.”
Water is surpassing oil as one of the most political and scarce resources worldwide. Nationally, water shortages are making headlines in communities, many of which now are abandoning decades-old irrigation methods and frivolous water use. But when one shifts to the global perspective and looks at factual situations like the Cochabamba Water Wars that the Bond film was based on, it becomes clear how real the battle for water has become. Many countries are trying to find or increase water supplies to alleviate sickness and death, and to support their agricultural and manufacturing capabilities.
Enter Solar Water Energy LLC (SWE), a U.S.-based desalination company that uses green water treatment and alternative energy technologies to generate new rivers of freshwater and substantially reduce our dependence on fossil fuels. The company is helping to solve the growing issue of water shortages worldwide and has built the world’s first solar desalination plant using U.S.-patented technology. Solar Distillation System (U.S. Patent #6,494,995 B1) uses solar power to convert seawater and saline water into fresh drinking water; Solar Thermal Energy Conversion System (U.S. Patent #7,127,849 B2) will generate renewable energy by converting stored energy into electricity. SWE’s first plant will be fully operational in January 2012.
The economies of entire countries are being compromised due to lack of access to water, threatening the life and health of more than 2 billion people.
In the past, scientists and engineers have built desalination plants to neutralize the problem, and in many instances they have been successful. However, conventional desalination systems are exorbitantly expensive, exhibit high energy consumption and are relatively inefficient. There is a growing need for a cost-effective desalination system to produce freshwater from seawater or contaminated water.
The amount of daily solar energy around the world is about 8,000 times the total energy produced worldwide, and capturing, storing and efficiently harnessing this energy has been the dream of generations of researchers. Today, this dream is starting to come true.
Freshwater and electricity are the newest power couple making the world go round. From the smallest village in Africa that relies on these wet and static sources for cooking, washing and heating, to the most industrialized nation that thrives on innovation, these resources are vital to the growth and development of an ever-demanding, constantly expanding global community. But cost-effective water and energy processing remains a hurdle that many countries cannot seem to circumvent.
Solar-powered desalination plants offer the opportunity to generate millions of gallons of freshwater at a fraction of the cost of other methods. In addition, the benefits of using solar power and its natural, clean properties greatly reduce dependence on fossil fuels. SWE understands the challenge and is moving toward a major solution. It markets its technology as a resource that is “providing green solutions for a thirsty world.”
“We believe that this technology is a strategic tool in the battle to combat desertification and begin using deserts worldwide for agricultural expansion,” said inventor and CEO Hammam Battah, P.E. “This new technology will help dying cities emerge from the brink of hopelessness, and help its citizens become major participants in the world economy.”
For many years, Battah sought the answers to two questions: How can solar energy make drinking water from brackish and seawater, and is it possible to convert the stored energy generated into electricity? Three years after filing his research, the U.S. Patent and Trademark Office granted Battah the two patents. In 2008, he formed a partnership with Perry Mehta, president and CEO of FutureNetGroup Inc., and established SWE. FutureNet Group is the international distribution partner for SWE.
The solar desalination plant at Sardar Vallabhbhai National Institute of Technology in India was constructed with steel and copper and will purify up to 60,000 gal of groundwater on campus each day.
“This plant will make the campus totally self-sufficient and will reduce the university’s annual water bills substantially,” Mehta said. “The world community is becoming increasingly aware that our natural resources will not last forever. So, our mission at SWE has been defined: Sustainability and renewing our resources are critical. It is a challenge, but our success will ensure that tomorrow’s generations will benefit from the sustainability legacies we accomplish today.”
Onshore & Offshore Solar Water Energy Plants
Conventional desalination systems are expensive to build and consume a great deal of energy, which makes them expensive to run. Capturing, storing and efficiently harnessing solar energy is the solution. SWE has developed the technology to optimize the natural resources of solar energy, ocean water and brackish water to produce life-sustaining potable water and electricity at a nominal cost.
Onshore solar distillation systems are contained in steel or concrete tanks over the ground and process groundwater or brine water. Solar energy increases the temperature within the water production structure, with minimum use of fossil fuels. The desalination process continues 24/7. Minimum production is 60,000 gal per day (gpd), and maximum production is 4 million gpd. The process uses little or no fossil fuel and averages 10% of the cost compared to reverse osmosis (RO). The average return on investment (ROI) is 35% annually.
Offshore solar distillation systems use floating solar cells over a body of water and basic thermodynamic principles to convert ocean water into freshwater and renewable energy. Solar cells are installed as close as 100 ft to the coastal line, and the depth of the structure is within 60 ft. Like onshore plants, the desalination process continues around the clock. A plant could cover a half acre and produce from 30,000 cu meters per day (cmd) to 400,000 cmd. ROI is 20% annually.
How the Process Works
Solar cells overlay a confined body of water in an evaporating tank. Water vapor is condensed in copper pipes under the cells. Heat consumed to evaporate the water is released back to the body of water when condensation occurs in the copper pipes, where it warms up the raw water.
Warmed water rises up toward the solar cells on top of the tank, where it is heated through solar rays. The resulting vapor is guided back to condensing pipes. The outcome is distilled water and some reject water.
Heat transfer is based on the patented technology. Designs are customized according to needs.
Water shortages are a brutal reminder that we can no longer take our natural resources for granted. More than 1 billion people lack access to clean water, and that number that is expected to grow to 5 billion in the next 50 years. Those who depend on wells are finding that groundwater is becoming less available and at risk of saltwater intrusion in many coastal areas.
Over the past few years, many people have turned to desalination systems, inluding RO, to solve their water shortages. But the expenses associated with RO—high energy consumption and maintenance costs, for example—far outweigh advantages for many cash-strapped communities and countries.
SWE water and environmental engineers apply their knowledge of intellectual water technologies to build onshore and offshore plants that deliver economic and environmentally sustainable solutions. They also have experience in all facets of the onshore and offshore environment—from intertidal regions to deep-sea ocean conditions, land and its adjoining areas, geographical information systems, and numerical modeling.
Each plant is based on a comprehensive, economic analysis that compares solar energy technology against other water processing systems in several areas, including maintenance, operating expenses, portability and energy consumption. A comparison between RO technology and solar desalination technology demonstrates that RO, which does not generate energy from renewable sources, uses extensive electrical power and adds to the cost of its operation. The possibility of bacterial contamination and pollution is ever present. In addition, RO plants have complex, costly setups, can only be established onshore and need fuel imports.
Plants do not use fuel but require minimum electricity, which makes them cost-effective to operate. There is no possibility of bacterial contamination or pollution, and it is assumed that plants will last 40 years. The lifetime of each plant is related to the disintegration of parts and materials due to high temperatures, ultraviolet waves, and wear and tear of the outer surfaces or protective covers of surfaces. It is important, therefore, to know what type of material and/or protective cover is used for the different components of the plants: copper, polyurethane or Flexiglass.
While James Bond’s futuristic “Quantum of Solace” may have fantasized the threat to our water supply as a greedy villain, worldwide water shortages are a reality. But we no longer have to wait for affordable, viable solutions. The technology is here and can be fully utilized as a strategic tool in the battle to combat desertification, give new life to dreams and future possibilities, and create new jobs and industries.