Learn more about EnergyEdge Online Training today!
About this Training Course
While current battery energy storage systems (BESS) are now firmly established as a mainstream solution to many power system balancing requirements, they run into limitations where larger amounts of energy need to be stored, for longer.
This 3-day course is designed to provide business people with a comprehensive picture of how other energy storage solutions will coexist and compete with current BESS solutions, particularly as power systems continue to evolve towards cleaner, more renewables-oriented supply mixes. The course will cover where and why energy storage can be considered ‘long’ and how extended energy storage requirements open up the market opportunity for a whole variety of alternative technological solutions.
While providing explanations of how these alternatives work, this course does so in a manner which is easily accessible and relevant to non-technical job functions, including a variety of commercial and business-focused roles from market analysis and business development to finance, policy and sales. Crucially in this respect, the course also evaluates and compares different potential LDES solutions not just from a technological standpoint but also by discussing pros and cons, barriers and risks, through consideration of practical deployment, economic structure and other project-relevant characteristics. In this respect, it will give technology developers a much more rounded and market-focused context in which to understand and develop their products.
Q1: What is long-duration energy storage (LDES) and why is it needed?
LDES refers to energy storage technologies capable of storing and discharging energy for many hours or even days — beyond the typical 2–4 hour range of lithium-ion batteries. LDES is essential as power systems integrate higher shares of wind and solar, helping balance supply and demand during periods of low renewable output. It improves grid reliability, reduces curtailment, and supports decarbonization of power markets by enabling firm, dispatchable clean energy.
Q2: How does LDES differ from conventional battery storage (BESS)?
While lithium-ion batteries dominate short-duration applications, they face technical and economic limits for long-duration use due to cost, cycle life, and resource constraints. LDES technologies — such as pumped hydro, compressed air, flow batteries, thermal storage, and power-to-fuel systems — offer longer discharge times, lower lifetime cost per MWh stored, and potential seasonal energy shifting. They complement BESS rather than replace it.
Q3: What technologies are used for long-duration energy storage?
LDES covers a diverse set of technologies, including pumped hydropower, compressed or liquid air energy storage, flow batteries such as vanadium and zinc-based chemistries, metal-air batteries and other emerging electrochemical options, thermal energy storage systems that convert power to heat or combined heat and power, and power-to-fuel approaches where electricity is stored as hydrogen, ammonia, or synthetic fuels for later conversion back to power. Each technology has its own efficiency, cost profile, and site requirements.
Q4: How is the cost of LDES measured?
The most common metric is Levelized Cost of Storage (LCOS), which accounts for capital costs, efficiency losses, O&M costs, and lifetime throughput. LCOS allows comparison between technologies on a $/MWh basis. Analysts also consider deployment speed, supply chain constraints, and real-world system benefits (like avoided curtailment or capacity deferral) to build a full business case beyond LCOS.
Q5: What are the main market and project risks for LDES?
Risks include technology readiness and performance uncertainty, high upfront capital costs, long development timelines, and competition with alternatives like peaking plants, interconnection, or CCS-equipped generation. Policy and market design also play a key role — inadequate capacity pricing or flexibility markets can undermine LDES economics. Mitigation strategies involve supportive regulation, clear revenue mechanisms, and staged project deployment.
Q6: What are the future trends and opportunities for LDES?
The role of LDES is expected to grow as renewable penetration rises and energy security concerns increase. Falling technology costs, hybrid systems combining BESS and LDES, and new market designs rewarding flexibility will expand deployment. Policymakers are introducing support schemes, pilots, and standardization efforts to accelerate adoption. Successful projects will integrate system modeling, LCOS optimization, and diversified revenue streams.