Energy storage technologies will likely offer the most efficient solution to smooth the variability in renewable energy output. Countries will need to build out energy storage capacity once they reach higher penetration of renewables.
In 2021, total energy storage capacity stood around 188 gigawatts (GW). The majority of this was pumped hydro storage (160 GW), accounting for around 90% of all storage capacity. However, battery storages are rising rapidly. Installed capacity of grid-scale batteries reached 28 GW in 2022, concentrated largely in China, Germany, South Korea and the United States. Capacity is also beginning to grow in other countries, such as India. Battery storage is forecasted to make up the vast majority of new storage under net-zero scenarios.
To limit warming to 1.5 degrees C (2.7 degrees F), the International Energy Agency (IEA) estimates that the world will need 585 GW of storage by 2030 and 3,100 GW by 2050. If the world reaches the level of zero-carbon electricity called for on this platform, it may require even more storage to balance variable output. There is not enough historical data to assess a trend for this indicator, so we are unable to assess how quickly the rate of change must accelerate to reach the 2030 target.