Electricity-hungry water providers need to get with the power

Age
3 January 2011 Page: 9

AS THE newly installed Baillieu government grappled with what to do with Victoria's money and energy-devouring reverse-osmosis plant at Wonthaggi, Australia's chief scientist, Penny Sackett, was on Lateline talking about her newly released report Challenges at energy-water-carbon intersections. During the interview she expressed doubts as to whether energy, water and carbon budgets were being dealt with holistically around the nation, adding that treating one independently could harm the others.

Sackett has good reason for her concerns. Water and energy have long been linked through the water cooling of power stations on the one hand, and the electrical pumping and treatment systems on the other, even before desalination plants came on the scene as emergency drought response measures.

In Britain, the water industry is the third most energy-intensive sector per unit of product surpassed only by cement and chemicals. In America, electricity is the second biggest budget item in municipal water supply. The link in our region looks set to tighten even more with the national industry body, the Water Services Association of Australia, predicting that water utilities will use four times as much electricity in their reliance on reverse-osmosis desalination.

If and when such a massive increase in energy use comes to pass, water utilities will be well and truly hocked to the fortunes of an electricity sector facing supply shortfalls across most states from about 2014-15 partly due to the carbon pricing hiatus, partly due to inertia in New South Wales and partly due to demand growth.

For some time now, it's been possible to integrate electricity generation and water making in the one facility. The trick is to use the waste heat from a high-efficiency combined cycle gas-fired power station to run a multiple effect distillation plant, which operates by progressively lowering the pressure at which water boils.

Combined cycle stations offer lower emissions, vastly improved efficiencies (typically much above, for example, the Loy Yang Power Station) as well as flexibility with the capacity for remote operation. Such groupings are commonplace in the Middle East, producing electricity during the times that it's most needed and fresh water when electricity demand tails off.

And, there's no chance of the "purified water" being contaminated by marine sewer outfalls, as the CSIRO has warned may happen with the Kurnell reverse-osmosis plant south of Sydney. These innovative packages were passed over in Australia, which has plenty of natural gas at suitable sites, seemingly on account of poor advice and a haste bordering on panic.

It didn't help either that there has been no regular dialogue nor awareness of each other's standpoints between water and electricity network professionals. Only two government agencies in this country ACTEW in the ACT and the Power and Water Corporation of the Northern Territory combine water and electricity, thus allowing an in-house exchange of ideas.

A recent report by Britain's Environment Agency has suggested that water companies merge with energy producers to create more effective partnerships for tackling emissions The local challenge is the mismatch between an electricity supply sector, which is deregulated and operates nationally often with offshore ownership, and a water industry that remains in government hands with a local focus. Still, private-public partnerships have proven that this is not necessarily a barrier.

Unlike south-east Queensland, where the Tugun reverse-osmosis plant has been mothballed (with dams now 99.9% full), Victoria appears to have little scope to vary the contract for, or scale back, its plant, since reducing the output volume requires lowering the number of filtration tubes but keeping the pressure up in order to maintain purity a messy task, according to engineers in the know.

Let's at least put some perspective on the urgency of achieving a greater integration between the water sector and the power industry, whether our judgment is based on cost efficiencies or on global warming scenarios. In a just-published report, World energy outlook, the International Energy Agency says the earth is on course to warm 3.5° by 2100 leading to a planet which NASA says is far from the one upon which civilisation developed and to which life is adapted.

To reach the 2° target, the energy agency found that every signatory at Copenhagen would have to hit the top of its range of commitments a task that would need a global rate of decarbonisation twice as large in the coming decade as in the last. There are several pieces of work which suggest that the job can be done with renewable energies, using gas as the transition measure. In the meantime, bridging the policy abyss between the two infrastructures has to be one of the "big ideas" for administrations to pursue and that is a challenge for the new Baillieu government.

Dr Peter Fisher works on climate change adaptation and water management. He recently jointly presented a ICE WaRM-AusAid short course on this topic for water professionals from five Mekong countries.