The renewable energy revolution is underway. The International Energy Agency predicts global wind and solar capacity will grow by a staggering 440 gigawatts by the end of 2023, shattering previous records. This unprecedented expansion of clean energy could lead to peak fossil fuel emissions as early as 2025.
However, supporting all that new renewable capacity poses challenges. Energy storage is essential to balance the variability of wind and solar power. Yet the energy storage sector remains small. It could expand almost 15-fold by 2030, potentially adding 387 gigawatts of new capacity according to one estimate.
Currently, lithium-ion batteries dominate energy storage. However their high costs, reliance on scarce materials, and short discharge times pose drawbacks. This motivates the hunt for innovative, sustainable long-duration storage alternatives.
One emerging solution is "natural batteries." These heat-abundant, cheap materials like sand, salt or rock to high temperatures to store thermal energy. The materials hold heat for weeks or months - much longer than lithium-ion batteries. Local and widespread, these natural batteries avoid supply chain pitfalls.
As one expert says, renewables are democratic - the sun and wind are universal. Natural batteries that store their energy locally using existing materials could be the missing piece to enable their full potential. Simple but clever, such innovations underscore how renewables and storage together can accelerate the clean energy transition.