Australia’s future electricity grid may be more resilient to climate variability than expected

On hot summer afternoons or still winter mornings, Australia’s electricity grid increasingly depends on the weather. As more wind turbines and solar farms replace fossil fuels, understanding how climate variability affects electricity supply has become an important question. 

And with Australia building an electricity system powered increasingly by wind and solar, one question has become more important – will the major modes of climate variability such as the El Niño-Southern Oscillation (ENSO) make it harder to keep the lights on?

Encouragingly for the projected renewable grid, new research from the ARC Centre of Excellence for the Weather of the 21st Century suggests the answer is largely no.

Researchers at UNSW Sydney examined how Australia’s three major climate drivers, ENSO, the Indian Ocean Dipole and the Southern Annular Mode, influence the balance between electricity demand and renewable energy generation capacity across the National Electricity Market.

The study found that while these climate patterns do affect temperature, wind and cloud cover, their combined influence on the electricity grid is surprisingly small.

Lead author Dr Doug Richardson, a 21st Century Weather Research Fellow, said previous studies had shown climate drivers could affect electricity demand, wind generation and solar generation individually, but this is the first study to examine how they work together across the grid.

“Once you combine electricity demand with wind and solar generation across Australia’s interconnected grid, many of those climate influences balance each other out,” Doug said.

The researchers analysed 84 years of weather data and modelled how the National Electricity Market would perform under AEMO’s projected expansion of renewable energy through to 2050.

They found that the grid becomes more dependent on weather as renewable generation grows, increasing year-to-year variability. However, large-scale climate drivers explain relatively little of that variability.

The Southern Annular Mode showed a modest influence, particularly during late winter and early spring, but ENSO and the Indian Ocean Dipole had only limited effects on the amount of electricity the grid would still need after wind and solar generation had been accounted for.

The researchers also tested whether information about these climate drivers could improve seasonal predictions of electricity conditions using machine learning models.

They found the climate patterns alone provided little predictive skill. Forecasts improved when temperature was included, suggesting the energy sector is likely to benefit more from better predictions of wind, solar radiation and temperature than from forecasts of climate drivers themselves.

Dr Richardson said the findings suggest Australia’s electricity system is likely to be more resilient to natural climate variability related to ENSO than many might expect.

“Climate drivers remain important because they influence Australia’s weather, but they’re not a reliable guide to how much renewable electricity the grid will generate overall. For future energy planning, improving forecasts of the weather itself is likely to deliver greater value,” he said.

The findings could help to guide future investment in seasonal forecasting for Australia’s energy sector as the transition to renewable electricity continues.

The research has been published in the journal Environmental Research: Energy and is available here.

This article was created using a combination of human and artificial intelligence.