Assessment of 25 Power Systems Exposes Gap Between Planning and Delivery
A structured evaluation of 25 major global power systems shows that system operators and regulators have made significant progress in flexibility planning, but actual delivery capabilities lag considerably. The analysis, covering regions including Australia, the ERCOT system in the United States, Brazil, Europe, China, India, Japan, and Pakistan, found that systems scored an average of 3.5 out of 5 in reliability decomposition and locational integration, indicating effective identification of grid reliability needs. However, the delivered resource portfolio scored only 2.8, the lowest among all assessed criteria, highlighting a pronounced gap between planning and execution.
The evaluation covered six key indicators: reliability decomposition and locational integration (3.5), market access and whole-system alternatives analysis (3.4), operational visibility (3.2), investability (3.1), correction capability (3.0), and delivered portfolio alignment (2.8). The analysis noted that while most systems can attract investment through mechanisms such as tenders and capacity auctions, integrating resources into effective flexibility portfolios remains a widespread challenge.
Diverse Sources of Flexibility, Varying Development Paths Across Systems
Cases from Norway and California illustrate distinct models of flexibility development. In 2024, 95% of Norway’s electricity supply came from renewable sources, with 83% derived from hydropower. Through reservoir management, grid operations, and integration with the Nordic electricity market, Norway has established a mature flexibility architecture without relying on large-scale battery storage. Norway also imports substantial electricity from Sweden, underscoring the critical role of regional interconnection in flexibility provision.
In contrast, California’s battery storage capacity surged from 500 MW in 2019 to 13,300 MW in 2024, a 26-fold increase. However, data from the California Independent System Operator (CAISO) for March 2025 showed wind and solar curtailment reaching 919,020 MWh, negative price intervals accounting for 18.13% of the time, and a three-hour net-load ramp of 19,959 MW. Despite the dramatic rise in battery capacity, California continues to depend on emergency resources and intertie assistance, revealing unresolved constraints in transmission, regional dependence, and gaps in other flexibility resources.
The analysis emphasizes that battery nameplate capacity is not a reliable indicator of grid maturity. Systems achieve flexibility through diverse combinations, including hydropower, transmission lines, demand response, flexible generation, and regional electricity trade. Experts stress that the key to assessing grid flexibility lies in whether it can fulfill reliability tasks, rather than merely the scale of installed technology. For instance, Norway’s hydropower and regional integration model contrasts with California’s reliance on battery storage, demonstrating different flexibility solutions.
The Reality Gap Between Project Pipelines and Actual Delivery
The assessment identifies a common misconception: treating project pipelines as operational capacity. Many systems announce gigawatts of battery storage or pumped-hydro projects and are then deemed to have achieved grid flexibility maturity. However, projects must pass multiple stages—including connection studies, permitting, financing, construction, and commissioning—before delivering flexibility benefits. The analysis specifically separates planned projects from delivered resources to avoid inflating actual maturity with tender or contract figures.
This gap has significant implications for investors, developers, and utilities. Experts advise that announced gigawatt-scale projects are merely the starting point for due diligence, not the endpoint. Stable revenue models, available grid connection capacity, permitting processes, financing progress, and actual system needs are the decisive factors in project success. For system operators and regulators, tender planning should align with specific reliability requirements, as different tasks—such as fast frequency response, intraday regulation, congestion management, peak shaving, multi-day adequacy, and strategic reserves—require distinct technologies and durations.
Grid Flexibility Shifts to Execution Challenge
The analysis concludes that grid flexibility has evolved from a problem of “lacking ideas, technologies, or market designs” to one of “execution.” System operators and regulators are increasingly adept at identifying flexibility needs and establishing corresponding mechanisms, but the scarcest capability now lies in translating these mechanisms into reliable operational resources, evaluating their effectiveness, and correcting gaps. The comparison of 25 systems shows that most grids remain in the planning phase rather than the delivery phase.
Experts emphasize that the future of grid flexibility hinges on closing the gap between planning and delivery. This not only affects the effective integration of renewable energy but also directly impacts grid stability and reliability. As the global energy transition accelerates, improving execution will become a shared challenge for power systems worldwide.
