It’s 12.45 on a warm, sunny December afternoon, NSW’s wholesale electricity prices are sitting below zero, but the forecast indicates a surge to the maximum price of $17,500 per megawatt hour in the evening peak.

In the control room of EnergyAustralia’s large Mount Piper coal power station near Lithgow, just beyond the Blue Mountains, operators are working to minimise financial losses, as prices drop to minus $9.50/MWh and solar generation floods the grid. They need to make sure they can capitalise on the expected spike later on.