Snowy Hydro-worth of solar and wind wasted in 2024, as curtailment continues to bite
New data has revealed that 4.5 terawatt-hours of large-scale solar and wind generation was curtailed over the course of 2024, equivalent to the annual output of the original Snowy Hydro scheme.
Energy curtailment, the deliberate reduction or shutting off of power generation, usually happens in response to overcapacity on the grid or when the cost of generating energy is higher than the market price being paid for its supply.
In Australia, renewables have been bearing the brunt of grid congestion management on the National Electricity Market – even though their output is cheaper and cleaner than coal and gas generation.
Victoria chalked up the highest total amount curtailment, mostly of wind generation but with a decent amount of big solar curtailment, too.
This trend reflects Victoria’s remaining dependence on brown coal generation, which has a limit on how low it can be constrained in the middle of the day.
The result is that despite high volumes of cheaper renewables, coal is dispatched and renewables curtailed.
This is a timely illustration of why “always on” nuclear power would be such a bad fit for the Australian grid, even at the level of renewables in the mix today.
Elsewhere, large-scale solar was almost exclusively curtailed in New South Wales and Queensland, while in South Australia it was wind that was most often pushed out of the equation.
Significant new big battery energy storage systems (BESS) being commissioned around the country throughout 2025 are expected to improve curtailment.
Hybrid projects and renewable energy hubs – where solar and/or wind farms are paired with a battery or a combination of the three - are also becoming a part of the solution.