Demand for long-duration energy storage (LDES) is rising as power grids seek systems capable of delivering energy for days or even weeks. While lithium-ion dominates today, it generally provides only about four hours of discharge, spurring interest in multi-day solutions.
BloombergNEF projects that LDES deployments will nearly quadruple in the coming year after a record 2025. China currently accounts for roughly 72% of cumulative LDES capacity and led installations last year.
The United States is positioning itself as a major challenger with a diversified technology slate and domestic supply ambitions. U.S. and European developers are pursuing iron-air, vanadium-flow, compressed air, thermal brick, and gravity-based systems rather than relying solely on lithium-ion.
This signals a broader, more resilient approach to grid storage and decarbonization.
Global demand and market dynamics for long-duration storage
As grids electrify and demand for reliable power grows, the need for longer-duration storage intensifies. The push is driven by the imperative to smooth irregular renewable output, ensure reliability during peak periods, and backstop energy security amid fuel-supply constraints.
While China currently dominates capacity and installations, the market is evolving toward a more competitive, technology-diverse landscape in North America and Europe. This shift is being reinforced by a growing pipeline of projects designed to discharge for multi-day intervals, a requirement that lithium-ion alone cannot satisfy without prohibitive scale and cost.
Technologies shaping the long-duration storage landscape
Industry observers emphasize a broad innovation frontier beyond lithium-ion. The leading contenders include:
- Iron-air systems, which aim to store energy in the chemical state of iron, potentially delivering high energy density at lower cost for multi-day duration.
- Vanadium-flow batteries, offering long cycle life and scalable capacity suitable for distributed networks and large facilities.
- Compressed air energy storage (CAES), exemplified by Hydrostor, which uses underground caverns or other reservoirs to store compressed air and release it on demand.
- Thermal brick storage, a form of heat-based storage that leverages bricks or concrete to hold thermal energy for extended periods and release it as electricity when needed.
- Gravity-based systems, which store energy by lifting heavy masses and retrieving it via gravitational potential energy—an approach gaining traction as a practical, long-duration option.
These technologies are often engineered as site-specific solutions, requiring local geographies, regulatory knowledge, and specialized integration with grids. LDES is less of a commodity and more a tailored service than a mass-produced product.
Regional momentum: U.S. and Europe vs. China
The competitive dynamic is shifting as policymakers recognize LDES as vital for deep decarbonization and grid resilience. China’s dominance in historical capacity and installations is clear, but a number of factors are leveling the playing field in the United States and Europe.
Local supply chains, skilled labor, permitting, and tailored procurement can reduce total project risk and improve time-to-install. In addition, U.K. and Italy are pursuing policy measures that encourage domestic manufacturing and deployment.
This further anchors LDES activity to national strengths rather than global commodity markets.
Policy and market design as enablers
Policy frameworks and market design play a central role in accelerating LDES adoption. Governments and investors view robust LDES platforms as essential for stability amid rising electricity demand and gas-turbine shortages.
Startups—Form Energy (iron-air) and Hydrostor (CAES)—are already signing commercial deals with utilities and data-center operators, signaling tangible traction and the potential for rapid scale in mature markets. The emphasis on local manufacturing, skilled labor, and regional energy hubs will likely intensify, supporting resilient domestic supply chains and faster project execution.
Industry signals and next steps
Analysts note there is no single technological leader in LDES today. The field is characterized by a race to deliver viable, cost-effective storage capable of 10 hours to 100+ hours of discharge.
This openness invites continued R&D, pilot programs, and commercial contracts as utilities and large users seek to reduce emissions, improve reliability, and hedge against fuel price volatility. The coming years are expected to reveal which combinations of chemistry, physics, and system design best meet regional grids and market economics.
Implications for decarbonization and grid resilience
Long-duration energy storage stands as a critical pillar of a resilient, decarbonized grid.
By enabling high-renewable penetration and smoothing intermittent generation, LDES can replace or delay costly peaker plants.
This unlocks substantial emissions reductions while delivering price and reliability benefits to consumers.
The ongoing expansion of LDES capacity—driven by diversified technologies, favorable policy environments, and strategic industrial partnerships—will shape how quickly and cheaply grids can transition to a clean-energy future.
Here is the source article for this story: The U.S. has a chance to rival China in rush for longer-lasting batteries