Nov 12, 2025
Pumped storage is leading the way in the global effort for long-duration energy storage.
A new global assessment of long-duration energy storage (LDES) indicates that pumped storage hydropower is still the most widely used and market-ready option in major economies, despite governments exploring various alternative storage technologies.
Conducted for Mission Innovation by Energy Systems Catapult, the study evaluated the technical feasibility and market conditions for 16 LDES technologies across 11 countries. While it covered technologies from hydrogen caverns to gravity systems, pumped storage distinguished itself due to its maturity, geographical adaptability, and access to revenue mechanisms.
Conventional pumped hydro ranked highest in deployment in nearly every country with suitable elevation and water resources. Australia, China, France, Germany, Italy, Spain, the UK, and the US scored well for both physical conditions and functioning markets.
The advantages are evident: pumped storage operates at scale, integrates seamlessly with existing power systems, and generates revenue through multiple markets, including arbitrage, ancillary services, and capacity mechanisms. In countries with cap-and-floor schemes for LDES like Australia, Italy, and soon the UK, pumped storage is particularly advantageous.
High-density pumped hydro and inverse pumped hydro were also evaluated, although their deployment potential varies significantly based on topography and access to deep water or underground space.
While several emerging technologies show potential, most do not have the geographical, commercial, and policy support that currently favors pumped storage.
Gravity-based systems, compressed air storage in caverns, and underground hydrogen storage are in planning or demonstration phases in various countries. However, these technologies face inconsistent market conditions and often rely on future policy changes, making it unlikely they will compete with pumped hydro soon.
Technologies like underwater compressed air, metal-air batteries, and hydro-pneumatic storage scored low due to limited operational experience and insufficient market signals.
Countries with clear LDES targets or broader storage goals create better investment climates. Public funding is crucial, especially for less mature technologies. Nonetheless, the report highlights that current markets favor frequent cycling, disadvantaging those meant for long-term energy storage.
Pumped storage mitigates this issue by participating in existing short and medium-duration markets while also providing long-duration system value when necessary.
Australia, Italy, and the UK were identified as the most supportive environments for LDES due to targeted market mechanisms. China and Germany have strong long-term potential, bolstered by funding and deployment activity, though they lack specific market structures for LDES. In all these nations, pumped storage remains the leading technology already functioning at scale.
As electricity systems incorporate more variable renewables, the report indicates that pumped hydro’s proven effectiveness in energy balancing and supply security will keep it central to long-duration storage strategies, even as new technologies emerge.
Conducted for Mission Innovation by Energy Systems Catapult, the study evaluated the technical feasibility and market conditions for 16 LDES technologies across 11 countries. While it covered technologies from hydrogen caverns to gravity systems, pumped storage distinguished itself due to its maturity, geographical adaptability, and access to revenue mechanisms.
Conventional pumped hydro ranked highest in deployment in nearly every country with suitable elevation and water resources. Australia, China, France, Germany, Italy, Spain, the UK, and the US scored well for both physical conditions and functioning markets.
The advantages are evident: pumped storage operates at scale, integrates seamlessly with existing power systems, and generates revenue through multiple markets, including arbitrage, ancillary services, and capacity mechanisms. In countries with cap-and-floor schemes for LDES like Australia, Italy, and soon the UK, pumped storage is particularly advantageous.
High-density pumped hydro and inverse pumped hydro were also evaluated, although their deployment potential varies significantly based on topography and access to deep water or underground space.
While several emerging technologies show potential, most do not have the geographical, commercial, and policy support that currently favors pumped storage.
Gravity-based systems, compressed air storage in caverns, and underground hydrogen storage are in planning or demonstration phases in various countries. However, these technologies face inconsistent market conditions and often rely on future policy changes, making it unlikely they will compete with pumped hydro soon.
Technologies like underwater compressed air, metal-air batteries, and hydro-pneumatic storage scored low due to limited operational experience and insufficient market signals.
Countries with clear LDES targets or broader storage goals create better investment climates. Public funding is crucial, especially for less mature technologies. Nonetheless, the report highlights that current markets favor frequent cycling, disadvantaging those meant for long-term energy storage.
Pumped storage mitigates this issue by participating in existing short and medium-duration markets while also providing long-duration system value when necessary.
Australia, Italy, and the UK were identified as the most supportive environments for LDES due to targeted market mechanisms. China and Germany have strong long-term potential, bolstered by funding and deployment activity, though they lack specific market structures for LDES. In all these nations, pumped storage remains the leading technology already functioning at scale.
As electricity systems incorporate more variable renewables, the report indicates that pumped hydro’s proven effectiveness in energy balancing and supply security will keep it central to long-duration storage strategies, even as new technologies emerge.