Two stories from today’s Sydney Morning Herald.
On the horizon, solar-powered tankers to slake Sydney's thirst
January 17, 2007
Richard Macey reports on a plan to build ships using wind and solar energy to transport water from Tasmanian dams to parched mainland cities.
THE dream of a transcontinental pipeline carrying water from Australia's wet north to the drought-stricken southern cities appears all but dead.
Rising from its ashes is a proposal to ship water from Tasmania to Sydney.
Five years ago Solar Sailor won an Australian Design Award for its electric catamaran, often seen plying Sydney Harbour. With rigid sails covered in solar cells, the boat catches the wind when it blows, or generates power from the sun when it shines. If the conditions are right, it can use both.
Now the company, chaired by the former prime minister Bob Hawke, proposes initially using conventional supertankers to ferry Tasmanian water to mainland ports.
Later it would use even bigger hybrid electric supertankers, powered by solar and wind energy.
Using ships to quench the thirst of Australian cities has been considered by a West Australian panel which studied ways to supply Perth with water from the Fitzroy and Ord rivers.
Led by Reg Appleyard, a professor at the University of Western Australia, the panel found a 1900-kilometre pipe supplying Perth with 200 billion litres a year would cost $12 billion to build, while a 3700-kilometre canal would cost $14.5 billion.
The energy needed to pump the water would generate at least 500,000 tonnes of greenhouse gases a year.
A third option, using ships, would cost $6.2 billion, but would produce 2 million tonnes of greenhouses gases.
The study found taking water from northern Australia would increase water costs at least fivefold.
"There is plenty of water; that's not an issue," Appleyard said. "It's getting it to its destination."
Piping water to Sydney would be no less costly and environmentally damaging, and unlikely to compete with desalination, he said.
But Solar Sailor's chief executive, Robert Dane, said there was a cheaper and greener solution.
North-west Tasmania had abundant water, he said, in hydro-electric dams just 15 kilometres from the coast and only a short sea trip from mainland cities: "The water is used once for hydro electricity. It is not used for irrigation or feeding a town."
Within 18 months a 50 billion-litre-a-year supply could be operating, using two conventional supertankers each ferrying 330 million litres to Sydney, the Central Coast, Melbourne or Queensland "just like delivering oil".
Within five years specially built electric tankers, each carrying 500 million litres, could be plying the routes.
The ships would be powered by rigid solar sails, coal-fired electric motors, or both.
The company proposes exporting up to 200 billion litres of Tasmanian water a year for 20 years, enough to supply almost a third of Sydney's needs.
The ships would moor on the horizon off Sydney and the water would be pumped through undersea pipes to Kurnell, then into Sydney's water supply.
It would cost about $1 a kilolitre, including a 30 cent-a-kilolitre royalty to Tasmania for water otherwise "going to waste".
If rain filled Warragamba Dam, the ships could sail to other markets.
Shaun Rigby, a spokesman for Tasmania's Water Minister, David Llewellyn, said no decision had been made: "We will listen to what they have to say, but we want more information."
NSW's Water Utilities Minister, David Campbell, said: "The Iemma Government does not see a need to ship water from Tasmania, because our water supply is secure."
However, "if private companies believe this is cost-effective and viable our [policy of granting third parties access to the water system] may open the way for this type of venture".
Nuclear waste containers will not work, say scientists
Wendy Frew Environment Reporter
January 17, 2007
CERAMIC containers developed to "immobilise" highly radioactive waste may not prove durable enough to prevent the toxic material leaching into the environment, research published in Nature has found.
Certain kinds of nuclear waste stay highly toxic for tens of thousands of years, and scientists have sought ways of stabilising or capturing the radioactive elements long enough to allow the waste to degrade naturally.
Researchers at Cambridge University directly measured the radiation damage from nuclear waste to the ceramic containers and found they degraded faster than had been expected. The research team, led by Dr Ian Farnan, found radioactive waste could turn zirconium silicate, which the nuclear industry had hoped could safely store radioactive waste, into a less reliable material after 1400 years instead of the desired 250,000 years.
Some governments, including Australia's, have touted nuclear energy as a partial solution to climate change, but environmentalists and some scientists have argued the radioactive waste generated by nuclear power plants creates a new set of environmental problems.
An Australian scientist said the significance of the British research was limited because it looked at only one kind of material. The senior principal research scientist at the Australian Nuclear Science and Technology Organisation, Greg Lumpkin, said the organisation had moved beyond zircon by developing a titanium-based material called Synroc.
"We left zircon behind years ago, but it has persisted as a model used by the industry," Dr Lumpkin said.
The Australian Nuclear Science and Technology Organisation had yet to commercialise Synroc but was pursuing partnerships with overseas organisations to have the technology adopted, he said.
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