Feasibility assessment of desalination application in Australian traditional agriculture

Within some data limitations, the paper provides a first assessment of areas in Australia with potential for implementing desalination technologies to supply agricultural water. At the national scale, these areas were identified based on a set of selected criteria: distance from land currently used for irrigated agriculture and feedlots; distance from town sites; exclusion of areas of environmental protection; exclusion of areas with surface elevation greater than 600 m AHD; and exclusion of regions with limited groundwater resources. Industries involved in the production of high-value crops are most likely to benefit from desalinated water as they use more-efficient irrigation practices and have the highest gross value of irrigated agricultural production. Groundwater was identified as the most likely feedwater source for cost-effective desalination, which is also the case worldwide. Brine disposal is a major factor in overall cost effectiveness of desalination. When feedwater salinity is relatively low, mixing permeate with feedwater leads to an increase in water production and a reduction in water cost. It was estimated that Australian farmers are unlikely to pay more than AU$1.2/kL for agricultural water. Generally for agriculture, desalinated water is still more expensive than water from other sources; however, there are likely to be circumstances when the costs could be comparable.