存储未来研究：四阶段框架与建模-51页_4mb

Storage Futures Study: Four Phases Framework and Modeling

Core Content Overview

The Storage Futures Study conducted by the National Renewable Energy Laboratory (NREL) explores the evolving role of energy storage in the U.S. electrical grid up to 2050. It introduces a Four Phases framework to categorize storage deployment based on its function, duration, and response speed. The study also analyzes the techno-economic aspects of various storage technologies, including batteries, concentrated solar power (CSP), and pumped hydropower storage, and evaluates their potential in different grid scenarios.

Key Findings

• Dramatic growth in grid energy storage is identified as the least cost option across all scenarios.

• The study outlines four distinct phases of storage deployment, each associated with different services, durations, and potential capacities:

  • Phase 1: Short-duration storage (≤1 hour) for operating reserves, with a national potential of <30 GW.
  • Phase 2: Medium-duration storage (2–6 hours) for peaking capacity, with a national potential of 30–100 GW, strongly linked to PV deployment.
  • Phase 3: Diurnal storage (4–12 hours) for capacity and energy time shifting, with a national potential of 100+ GW, depending on Phase 2 and variable generation resource deployment.
  • Phase 4: Long-duration (days to months) storage for multiday to seasonal energy time shifting, with a national potential ranging from 0 to more than 250 GW.

• Storage costs are projected to decline significantly beyond 2020, with reductions ranging from 21% to 67% by 2030.

• PV integration is a major driver for storage deployment, particularly in Phases 2 and 3, where it increases the need for peaking capacity and energy time shifting.

• Grid operational modeling and scenario analysis are central to the study, using the ReEDS and dGen models to simulate storage deployment and its impact on grid performance.

Key Viewpoints

• Phase 1 is dominated by operating reserves, which require fast response times (milliseconds to seconds) and are essential for grid stability.
• Phase 2 focuses on peaking capacity, where battery storage plays a growing role in replacing fossil fuel-based peaking plants.
• Phase 3 involves diurnal storage, which is critical for managing the variability of renewable energy sources, particularly PV, and supports energy time shifting and dispatch efficiency.
• Phase 4 is necessary for seasonal energy storage, addressing the mismatch between renewable energy generation and demand over longer timeframes.

Critical Information

• The study includes 19 scenarios based on different combinations of:
  • Variable Renewable Energy (VRE) costs (wind and PV)
  • Storage costs (batteries, pumped hydro, CSP)
  • Natural gas prices
  • Transmission costs
• Grid-scale diurnal storage scenarios are modeled using the ReEDS model, which simulates the dispatch of generation, storage, and transmission for each hour of the year.
• Distributed PV + storage adoption is analyzed to understand the impact of decentralized storage on grid operations.
• Capacity value is a key driver of storage deployment, but energy arbitrage value is also essential for optimizing storage use.
• Battery storage is expected to be competitive if it can meet the cost and performance criteria outlined in the study.
• Residual load duration curves and net load profiles are used to assess the need for firm capacity and the value of storage in different regions and under various renewable penetration levels.

Cost and Performance Trends

• Battery costs are expected to decline significantly, which will influence the economic viability of storage systems.
• The study provides cost breakdowns for different components of battery systems and highlights how cost reductions in battery packs will impact overall system costs.
• Marginal cost and benefit/cost ratios are used to evaluate the economic value of storage systems in providing different services.

Conclusion

The Storage Futures Study offers a comprehensive framework for understanding the role of energy storage in the U.S. grid through 2050. It emphasizes the importance of cost-effective deployment, renewable integration, and grid operational impacts. The four-phase model provides a structured approach to analyzing how storage technologies can support the transition to a more sustainable and resilient energy system. The study also underscores the potential for significant storage growth (>125 GW) in all scenarios, driven by the increasing adoption of renewable energy and declining storage costs.