Wave-Powered Desalination System

Over 1 billion people suffer from the effects of water scarcity. The vast majority of those affected live near a coastline in developing countries, on islands, and in remote communities. To satisfy the potable water needs of a growing world population, experts agree that seawater desalination on a large scale is required. Near-shore ocean waves provide an inexhaustible, consistent, and widely distributed energy resource accessible to a high percentage of the world population. An oscillating flap wave energy converter coupled with a novel seawater compatible pump has been proposed for powering reverse osmosis desalination systems, thereby eliminating the need for costly and environmentally damaging diesel generators and oil-based hydraulic fluids. Although extensive component modeling and development has been accomplished to date, further detailed modeling is required to validate integrated system performance and the cost of water produced. The proposed Phase I work will create an integrated suite of numerical models to assess the dynamic performance of a wave-powered, reverse osmosis desalination system utilizing flap driven pumps to directly pressurize sea water for delivery to an on-shore desalination plant and a supporting electric “house-power” generator. Models to be developed and integrated include oscillating flap hydrodynamics and pump reaction as a function of specified sea conditions, flow control valves and hydraulic accumulators in the water delivery circuit, piping dynamics and losses, the reverse osmosis desalination plant, the house-power electric generator, and overall plant control policy. Results of model execution and analysis will be used to provide input for overall system costs and levelized-cost of water analysis, and preliminary design of a laboratory-scale, hardware-in-the-loop prototype to enable validation and adjustment of the concept and models and accelerated life testing of key components. In addition to solving water security issues, wave-powered desalination plants may provide a quiet, low-cost water supply for resorts, marinas, and seaside communities interested in capitalizing on their renewable energy resources. Additionally, the technology may be configured to provide electric power exclusively, thus enhancing the portfolio of renewable energy options available to consumers and electric power providers.