Desalination techniques - A review of the opportunities for desalination in agriculture

The adoption of desalination for agricultural purposes in countries such as Australia has been very limited, with only a small number of cases available to demonstrate its suitability. This can be compared to countries such as Spain where the uptake has been significant. A number of suitable technologies such as reverse osmosis and electrodialysis are available to provide desalinated water, but not at a cost comparable to that for water commonly utilised for agricultural purposes. The use of blended waters, where the quality of the water is tailored to the crop may go part way to addressing this cost differential. However, if the overall efficiency of the combined production of water and food, as well as opportunities for better soil management is considered, then desalination's applicability to agriculture becomes more viable. The use of state of the art technologies for the provision of desalinated water for agriculture is most likely to be cost effective in a tightly controlled environment, using agricultural practices with the most-effective water use and crops with high productivity. Such conditions are often associated with greenhouses and the production of high-value irrigated crops, where the cost of water is small compared to the infrastructure investment.