Australian desal demands better planning
Posted 8 August 2016
A shortage of long-term planning has hurt the desalination industry in Australia but the technology is set to be of increasing local importance, says an international expert.
The University of Oklahoma's Jadwiga Ziolkowska has been comparing the world's leaders in desalination and studying what makes them successful.
“Australia’s desalination got stigmatised because of mothballing that never happened in other countries at that scale in the entire history of desalination,” she said.
In her recent journal paper – Desalination leaders in the global market: current trends and future perspectives
– Ziolkowska compared the USA, Saudi Arabia, Israel, Australia and China.
Ziolkowska said Australia could learn from other countries' practices.
“In Australia, many desal plants were built in a rush during the Millennium Drought, and without a long-term plan to incorporate desalinated water in municipal water portfolios,” she said.
In the United States, Saudi Arabia and Israel, the vast majority of desalination plants supplied municipal users.
But Australia wasn't alone in having plants reduced to minimum capacity, with the total capacity of mothballed plants in the world totalling more than 565ML a day in 2013.
“As of 2013, [there were] six mothballed plants in Australia, while two additional plants were decommissioned, three on hold, and one cancelled,” the paper states.
While decommissioning mainly occurs due to the end of the lifetime of a plant or due to technical problems, mothballing can be concerning if it occurs at a larger scale.
Since the 1950s, the US has had 22 plants decommissioned, three cancelled and six put on hold, with many smaller plants classified as ‘presumed offline’.
China and Israel each had one plant cancelled, while a further six plants were put on hold in Israel and Saudi Arabia.
“Despite positive feasibility studies for those desalination plants constructed specifically with the purpose of mitigating the negative effects of drought, the costs of providing desalinated water in the wet years following the drought are much higher than the costs for freshwater from aquifers or surface water,” the paper states.
Desalination water source salinity is another factor adversely impacting Australia by driving up costs, with Australia found to have one of the highest amounts of seawater desalination (75%), second only to Israel (93%).
“Desalination of brackish groundwater is least expensive due to lower salinity levels and the relatively low energy costs associated with the desalination process,” the paper states.
Ziolkowska found all of the analysed countries needed new, more cost-effective water technologies, and public-private investment in research and development.
“Right now, prices for desalinated water are still two to three times higher than for water from traditional water sources [groundwater/surface water], which rubs off on social acceptance of desalination,” she said.
“This is universal for all countries around the world. While some countries in the Middle East (for example, Saudi Arabia) have very low prices for desalinated water, this is because desal is heavily subsidised by the government.”
Despite the challenges, Ziolkowska was optimistic about the future.
“Desal is the answer to water problems of the future – the world is drying out and droughts are hitting more and more frequently in an increasing number of countries around the world. Desal will be ‘our daily bread’ in the near future,” she said.