Australia Turns to Desalination Amid Water Shortage

Last night's news carried a research claim that stated increasing CO2 levels will make Australia greener due to faster plant growth and reduced water consumption by plants via reduced stromata size. Seaplaneguy will be chuffed.

On the other hand we have the usual empty vessels claiming single events such as the rough weather on the NSW coast as "Proof". I'm not sure how they explain historic events such as the 1955 hunter River floods, history is a hell of an impediment to a good sensational story. What a pity journalists seem to have not studied any.

Location South East Qld.

My front lawn is a golden brown, the swimming pool is empty and have level 5 water restritions coming into force, I also remember the once in a hundred years flood back in 1974. And our dams are running dry? I think this is due too more than just golbal warming, like not planning for an expanding population, and slow to move off theirs butts because of the expence. As for Western Australia the wind turbines are probably the point of interest, they have an advantage as they have strong winds that come up from the south pole, (nick named the doctor), that blow quit regularly.

If the grass is going to get greener I've yet to see it.

Still raining in Mackay. Last two years were drought though. Our water restrictions are due to lack of treatment capacity (or cost cutting) as the weirs are flowing over.

I also heard a story on NPR about camels in the deserts there, and they said that rainfall in the desert had actually been up for the past 10 years and the camel population has exploded.

Here in South East Australia - Melbourne - we have had a drought for around six years - some say ten years.

Before the last election in late 2006 the Labour Government - which was returned in that election - strongly criticised the opposition in its proposal for a desalination plant. Yesterday they announced that they intend to build one and are only discussing the location. Some normal turnaround by Government.

Rumour has it that they have been over to Perth to study the plant there.

We too have quite a bit of wind available, but have the normal objections that they "spoil" the skyline. After all the view is much more important than having air to breath and water to drink.

Australia's eastern food bowl is badly affected by the drought with a threat of no water allocation in the coming season for farming and irrigation in the Murray-Darling basin which covers much of Queensland, New Soth Wales and Victoria. Perhaps we should look at a larger unit to bring water to the Murray and Darling rivers too.

Maybe that is too much foresight!

I believe that most big cities will eventually have to go to desalination. Hopefully without pollution generated power

I live here & I had,n,t heard about the plant being wind powered- I thought the idea was to put up wind generators to take the place of coal, as used presently. They are also trying to build another desal plant on the coast further south, but the locals are (nimby)-I honestly fear the amount of sea water being used, & the salt effluent put back, will lead to dire consequences on the fish population, & also the level of the oceans, as when extrapolated world-wide. As to climate change here, it ain,t too bad- just lately (2 years) about half winter rainfall- some places have less rain, some have more- but thats life- there never have been any guarantees.

If you want to get the low down, try googling "perth seawater desalination plant".

The process is one of reverse osmosis & is powered by a wind farm some 120 kms north of Perth.

A second plant is being considered & may be powered by wave energy.

Greg Lynch

Greg, are you saying that the windfarm has dedicated power lines for 120 km sth to RO plant, or are you saying the windfarm output is fed to the grid?- a completely different thing in my humble opinion.

The wind farm feeds into the existing grid. As i am sure you will appreciate, as with all sources of solar energy, it can not be relied upon to supply continuous power. The wind farm is purported to supplement the grid to the extent of the energy consumption of the desal plant. That's the thinking ... will it, will we ever really know. I'm sure you have been around long enough to wonder about anything a politician spruiks. In theory it should work, provide the generating capacity has been installed to allow for the windless periods.

Greg Lynch

Another interesting proposal is one wherein a wind powered equipment extracts the abundant supply of water present in the atmosphere.

Regards

Greg Lynch

I guess solar energy could be trapped into large pools covered by glass greenhouse with corrugated channels to collect vapor under the glass roof.

Yes Guest, this was demonstrated on a small scale for water recycling in arid areas and third world situations on our "New Inventors " TV Program last year.

The units were the size of a small table and had specifically shaped 'wells' in the black plastic base to avoid the water rushing through and to assist in capturing heat.

Apparently quite successful on a small scale in a hot sunny climate being able to supply several litres of drinking water per day from every square foot prvided the water was kept up to it by a float valve.

Enough water was flushed through each night to clean out sediment.

Really? Several liters per day per sq foot? That's impressive.

A boat captain friend of mine has told me they use the same sort of tool when out at sea. But like Bhankiii, I was unaware they were so effective... Can these units be used only for salt water or do they also work on say, river/lake water (is only pure water being evaporated)?

I can not guarantee that the figures are accurate because I am only quoting the inventor on the TV program. He did say that it was meant for the very hot areas such as the Sahara or central Australian desert type of climate.

And yes it gives clean water from any water source whether sewage or sea water or any other source like to local "dirty" well. The resulting water is apparently close enough to "pure" for dinking.

Unfortunately there was not a lot of information on the design or shape of the black plastic base to maximise the heat retention within the "greenhouse" construction. I do remember that the corrugated clear "roof" was sloped and shaped to encourage the water to flow down along the inside to the collection point which drained into a sealed container.

I have also heard of a system for condensing water vapour from the atmosphere which could be wind powered but have no further details on efficacy, or whether it has ever been built. I must try to follow it up.

The invention you are referring to is by a Perth man, referred to as a genius. Though I have missed the tv programs that showed it, others have told me of the principles- basically a propellor mounted on a fridge type compressor- the wind turns the propellor- & the moisture in the air condenses on the evaporator, which drains into a receptacle- supposedly 2-3 litres a day on the small test setup- extrapolated, it seems a very practical way to get some of that moisture down that previously fell reliably as rain!.

Thank you Neil.

If you find out anymore about it I would like to know.

The person I spoke to about this was in Brisbane, but I don't think he has got it going yet.

Seems highly probable that it could be used for outback domestic drinking water supply.

I have a hard time imagining these units on a very large scale but maybe the future will be more on the "domestic" side (at least in some areas). Everybody could make their own drinking water; imagine how many diseases could be avoided if safe drinking water was available.