Tuesday 11 June 2013

A salty story

There was an item on the radio last night looking at the desalination plants that China is building on its east coast. Its fast-growing cities are hungry for water, springs are drying up - so what to do? The answer, for China, is to throw technology at the problem.
There was an interview with the manager of a desalination plant, still only one-fifth built. As such plants go it is, apparently, fairly green. It uses the waste heat from electricity production (mark however that it is electricity from coal, the most polluting and greenhouse-intensive fuel source) in the desalination process. And rather than throwing away intensely salty water as a byproduct, it dries it out and sells the salt for industrial use.
So at least good points there. But they also interviewed an environmentalist. (I suspect that criticising such a policy is a brave thing to do in China). He talked about the energy consumption of such plants, which is likely to be an issue - I cannot imagine that with huge expansion it can all  come from CHP), and the cost of pumping the water. That, I suppose, depends how far it has to go, since all water has to be pumped unless you live on top of a spring.
And he said the answer is to learn to use water more wisely. Wise nods. But I am sure that our per capita consumption is way higher than China's. Of course installing massive desalination plants is a bad idea. But if we want to condemn it, we need to think more seriously about how we are dealing with water in this country. It's time to get a water butt.


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