Comments on: Diminishing returns on urban water

By: Nick Mallory

Nick Mallory — Mon, 05 Nov 2007 18:35:16 +0000

Tired of politicians never listening to a word you have to say?
The Australian Government is thinking about setting up a ‘blog’ to let the public have their say on public policy.
Have your say on what shape it should take here
http://www.openforum.com.au/Survey
Yes, it’s for real.

By: Arjay

Arjay — Sun, 04 Nov 2007 22:41:27 +0000

Ross Carpenter,come on,talk about splitting hairs,you know what Graham meant.There is less available water because of changing climate change and the growth of human populations.At least make a valid criticism that finds flaws in arguments not semantics.

By: Ross Carpenter

Ross Carpenter — Sun, 04 Nov 2007 10:54:22 +0000

The beginning of this articel “There’s less water than there used to be…” is erroneous. The earth is a closed system there cannot be less water. The distribution of water and it’s variability is very much of cilmate change, something that has been happening since the planet was formed. The climate changes, we as humans may not like the results.

By: Arjay

Arjay — Thu, 01 Nov 2007 19:15:08 +0000

Before Bob Carr went to the Middle East,he described desalinated water as bottled electricity.When Bob returned from his little junket,he waxed more lyrical than all the reseviors in Kevin Rudd’s ears.NSW had to have desal.
We were told that desal water would cost us double,but now learn it will cost us 5 times that of dam water and the plant itself will cost much more.
There is something deeply suspicious about ex-pollies who do extreme reversal of attitudes and then work for organisations such as the Macquarie Bank who secure Govt contracts.
Perhaps we should stop criticising Indonesia and tidy up our own backyard.
PS,Recycling sewage is far cheaper.but state Govts can make more money selling us bottled electricity.

By: Evan

Evan — Thu, 01 Nov 2007 07:16:29 +0000

Water restrictions are turning deadly ... http://www.abc.net.au/news/stories/2007/11/01/2078076.htm

By: Jennifer

Jennifer — Wed, 31 Oct 2007 15:14:31 +0000

We are actually going without water now. For example, there are significant restrictions on water use in Brisbane.
Desalination plants can supply water whether it rains or not. Furthermore if the source of energy is, for example, nuclear, we could have our water without carbon emissions.

By: Sylvia Else

Sylvia Else — Wed, 31 Oct 2007 10:13:54 +0000

I share your doubts about how real the carbon credits are. The presence of intermittent power generators like wind farms, and solar power systems, forces other parts of the generating system to operate in less thermodynamically efficient ways to allow them to compensate for variations in the intermittent output. Thus those other generators produce more CO2 per unit electrical energy than they would have done in the absence of wind and solar power. This effect should be taken into account before wind and solar plants are given their carbon credits.

By: Sylvia Else

Sylvia Else — Wed, 31 Oct 2007 10:07:31 +0000

If we don’t build the desalination plants, will the greenhouse problem go away, so that we don’t need them? No, it won’t, so by not building them we would be burying our heads in the sand, given that we need the water.
Although desalination consumes energy, the description “energy intensive” needs to be seen in context. The average domestic consumer uses more energy to heat the water for their shower each day than would be used to desalinate their entire water usage.
I don’t think the greenhouse gas credit requirement will make much difference to the cost. Although it feeds into the cost of energy for desalination, by far the major cost component of the water produced is the capital investment required for the plant. Add that to the unchanged cost of delivery to the tap (about 90 cents per kL in Sydney) and the consumer won’t notice the difference.