As the world moves towards a carbon-neutral economy, engineers are working hard to understand how clean power can most effectively be stored and brought on to the grid, with many challenges to factor in such as the intermittent nature of clean energy sources like wind and solar. The key to keeping clean energy available around the clock lies in cutting-edge storage solutions.

Until now, energy storage has mostly been deployed through hydro pumping systems, which use storage reservoirs to run generators. Batteries are another obvious storage mechanism. However, engineers now believe that gravel and sand could be used to store clean energy in mountainous regions. 

Called Mountain Gravity Energy Storage, this technology would take excess clean energy from the grid and raise gravel or sand to a higher elevation with cranes. The matter would be loaded into storage containers at height. When power was needed at the grid, the material would be dropped to the lower storage site using gravity, turning a generator to create electricity. The same motors used to lift the sand or gravel could be used to generate the electricity.

This theory basically uses the theory of hydroelectricity reservoir pumping, which uses dams and water flows to turn turbines. However, they tend to only be viable for large installations, whereas MGES could be useful for smaller power outlets, such as for isolated communities or islands where clean energy is still in demand.

This interesting new technology is currently in development, but it does point to the possibility of an interesting new turn for clean energy storage and yet another enabler that allows communities across the world to move away from damaging fossil fuels and to embrace renewable energy in a sustainable, economic and reliable way.