Intermittency

A new word has entered the fashionable lexicon. The global warming alarmists and the "dark green" advocates of the Murray Darling Basin Plan had better get used to it and learn how it impacts their advocacy arguments.

I have long contended that the massive variability of our river flows makes the use of statistical averages quite meaningless, when the spreads around the average are so enormous. Asking CSIRO to come up with Annual Volumetric Limits (AVL's) for each of the major rivers in the MDB is a stupid question from people who clearly don't understand the the key characteristic of our inland rivers-massive variability.

Likewise the promoters of renewable energy, particularly wind and solar, talk about single figure targets without acknowledging the dependence on the wind blowing and the sun shining to achieve them. If energy sources are to be dependable then the "intermittent" sources need to have back-up or significant storage capacity, to achieve the reliability requirement. Without subsidies this makes them quite uneconomic! 

Hydro is a notable exception, because you can store the water and achieve immediate generation with the turn 'of a tap', making hydro ideal for peak electricity generation. A fact that Snowy Hydro has exploited brilliantly. I remain to be convinced that "pumped hydro" will prove economic, where water has first to be pumped to higher altitudes and then run back down to drive the generators.

But, take my word for it, we are going to hear a lot about "intermittency".