In Australia’s electricity system, more and more energy from sunlight and wind is being “spilled” – or not converted to electricity. In the past year, the amount of renewable energy spilled was roughly equivalent to the annual consumption of 750,000 typical households, or three months of consumption for the state of South Australia. Some have attributed these dynamics as being driven by a “solar power glut”.
At face value, this seems like a terrible waste of renewable energy, even more so in the face of a slump in rate of renewable energy growth and the pressing need to reduce emissions.
But the story is more complex. Such spillage, also known as curtailment, is also an expected and efficient feature of renewable energy systems.
What is ‘spilled energy’?
The energy market operator defines spilled energy as “energy from variable renewable energy resources that could be generated but is…


