A very lucid reader has contacted PWF about several infrastructure projects to which there have been viable alternatives but which have not been discussed in a public forum.
Let’s have that discussion… starting with drought-struck Victoria’s desalination plant at Wonthaggi.
Politically there is bi-partisan support for the Wonthaggi desalination plant – so dire are Victoria’s water storage levels – but the project, foisted on an unsuspecting coastal community, is opposed by many local groups and the Bunurong Indigenous people of south-east Victoria.
The Age newspaper reported 31 July 09 that
“If all goes to plan, work will begin in October, creating 1700 jobs. Water will begin flowing to Melbourne by the end of 2011 and water restrictions in Melbourne will be eased from 2012…
The estimated cost of the plant has already blown out by about $400 million in two years, from $3.1 billion …to $3.5 billion…
(Premier John Brumby says) the project is ‘fully funded’, through the biggest private-public partnership forged anywhere in the world since the global financial crisis struck.
But there is a catch. The private consortium commissioned to build the plant wants to ‘diversify its investment base’…
In other words, it intends to sell down its debt to superannuation and pension funds and other private investors — in an extremely tight market.
The Victorian Government has agreed to be the ‘lender of last resort’, in the event that the private consortium can’t find the funds elsewhere.
The Opposition calls this a ‘funny money’ deal, but Brumby asserts there will be no problem.”
The proposed Wonthaggi project will use a reverse osmosis system (RO) but there is an alternative. In the Middle East waste heat from power stations is used to desalinate seawater via a thermal desalination process rather than by RO.
REVERSE OSMOSIS squeezes water through a very fine membrane to remove salt and impurities from seawater.
This membrane system requires many people, continually, to operate.
THERMAL DESALINATION is a multiple effect system that uses the latent heat (energy to change from water liquid to water vapour) many times over so that the equivalent heat for 1 kg steam may produce about 10 kg pure water.
In effect this system mimics the sun, using heat/thermal energy to evaporate water which is then recaptured through condensation – like catching drops of water from a sloping shower roof.
This system requires only a man hour or so a day to operate.
Both processes are energy intensive
with thermal desalination you can use waste heat from an industrial process such as power generation in Victoria’s Latrobe Valley or Newport Power Station (at the mouth of the Yarra) where fresh water is currently used for cooling.
NB I am advised that a government paper comparing RO and thermal desalination found that RO was much cheaper. True, BUT this is NOT the case when WASTE ENERGY is used – as COULD be done all along our coastline where there is industry exhausting heat energy into the atmosphere.
In the Latrobe Valley – home to five brown coal fired power stations – or at natural-gas powered Newport, where fresh water is currently used for cooling or ‘rejecting heat’ and this heat/thermal energy is not used/wasted.
This thermal energy could run thermal desalination plants as is being done in the Middle East.
Pipe coastal seawater to a tank near one of the power stations then pipe the processed fresh water to Melbourne’s existing water supply infrastructure such as Gippsland’s Thomson Dam.
It MIGHT be more expensive but is better environmentally and a lot of the infrastructure is already there.
Was this alternative ever considered?
The contract has just been let, but the funds are not there yet.
Discussion of these ideas is invited..