Australia’s power grid is fast changing, driven by a surge in solar energy. During a recent heatwave in the south-east, solar power supplied 30% of the total electricity on the main grid covering five states and the ACT. From 9am to 6pm, solar met 59% of electricity demand. Small rooftop solar systems contributed 37.6%, with the rest from large solar farms. Dylan McConnell of the University of New South Wales noted solar output peaked at 67% of consumption between 12pm and 1pm, reaching over 70% in New South Wales and South Australia. Coal-fired power, which once supplied nearly 90% of electricity, now plays a smaller role. It supplied just a quarter of the electricity during peak solar hours due to higher costs. At night, coal, along with wind, hydro, batteries, and gas, provided most power. The grid still depends on coal plants for stability, but the share of renewable energy is now almost equal to coal over the year. The Australian Energy Market Operator called the last quarter of 2025 a “landmark moment” as renewables passed 50% generation for the first time, coinciding with a 44% drop in wholesale electricity prices compared to 2024. Battery output tripled over the past year, essential for future coal closures. Five years ago, renewables made up 26% of power; a decade ago, under 15%, with solar under 2%. McConnell highlighted how well the grid coped as temperatures tipped over 45°C, with high air conditioner use but very few issues or blackouts. While the transition to renewables is historic and underway, experts warn investment must speed up to meet climate goals and replace aging coal plants. Some political players resist the shift, but the change in Australia’s electricity system is clear and effective.