Desalination and energy consumption. What can we expect in the near future?

Abstract

Desalination technologies have become necessary tools for hydrological planning, along with conventional water resources. One of the main barriers to extend desalination is higher water costs, which are seriously influenced by energy consumption (represents > 50–60% of total costs). This paper takes into account relevant energy and desalination aspects and different available technologies. This work focuses mainly on reverse osmosis, which is the most widely used technology. It also considers aspects like major consumers and their contribution to overall. The configuration of HP pumps, membranes and ERDs is explored, as is what we can expect in the future, while we bear in mind that we are currently very close to reaching the thermodynamic limits for energy consumption. Special dedication will be taken to renewable energies and how they can be combined with desalination to produce more efficient systems, though not necessarily directly coupled to desalination plants. How to choose the most adequate energy rates and the production plus storage combination is another important consideration to optimize energy costs. An adequate production management strategy can significantly reduce the cost of water. To conclude, emerging technologies are analyzed, by looking at all the possible improvements and potential generated uses.