The announcement of a $650 million solar power plant near the South Australian town of Port Augusta brought forth the usual statements that such a plant would produce reliable or dispatchable power.

But anyone with experience of renewable plants would have looked in vain in the announcements for usable information on the plant’s performance, including an estimate of the plant’s capacity factor, or for an explanation of why the South Australian government of Jay Weatherill is getting power apparently so cheaply from an expensive and still largely unproven way to generate electricity.