Energy storage at all timescales, including the seasonal scale, plays a pivotal role in enabling increased penetration levels of wind and solar photovoltaic energy sources in power systems. Grid-integrated seasonal energy storage can reshape seasonal fluctuations of variable and uncertain power generation by reducing energy curtailment, replacing peak generation capacity, and providing transmission benefits. Most current literature focuses on technology cost assessments and does not characterize the potential grid benefits of seasonal storage to capture the most cost-effective solutions. We propose a model-based approach for comprehensive techno-economic assessments of grid-integrated seasonal storage. The approach has two major advantages compared to those presented in the literature. First, we do not make assumptions about the operation of the storage device, including annual cycles, asset utilization or depth of discharge. Rather, a model is used to calculate optimal storage operation profiles. Second, the model-based approach accounts for avoided power system costs, which allows us to estimate the cost effectiveness of different types of storage devices. We assess the cost competitiveness of three specific storage technologies including pumped hydro, compressed air, and hydrogen seasonal storage and explore the conditions (cost, storage duration, and efficiency) that encourage cost competitiveness for seasonal storage technologies. This study considers the Western U.S. power system with 24% to 61% of variable renewable power sources on an annual energy basis (up to 83.5% of renewable energy including hydro, geothermal, and biomass power sources). Our results indicate that for the Western U.S. power system, pumped hydro and compressed air energy storage with 1 day of discharge duration are expected to be cost-competitive in the near future. In contrast, hydrogen storage with up to 1 week of discharge duration could be cost-effective in the near future if power and energy capacity capital costs are equal to or less than ∼US$1507 kW⁻¹ and ∼US$1.8 kWh⁻¹ by 2025, respectively. However, based on projected power and energy capacity capital costs for 2050, hydrogen storage with up to 2 weeks of discharge duration is expected to be cost-effective in future power systems. Moreover, storage systems with greater discharge duration could be cost-competitive in the near future if greater renewable penetration levels increase arbitrage or capacity value, significant energy capital cost reductions are achieved, or revenues from additional services and new markets—e.g., reliability and resiliency—are monetized.

中文翻译：

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季节性储能技术对风能和太阳能发电的价值

所有时间尺度（包括季节尺度）的能量存储在提高风能和太阳能光伏能源在电力系统中的渗透水平方面都起着关键作用。电网集成的季节性能源存储可通过减少能源消耗，替代峰值发电能力并提供输电效益，重塑可变和不确定发电的季节性波动。当前，大多数文献都集中在技术成本评估上，并未描述季节性存储潜在的网格优势以获取最具成本效益的解决方案。我们提出了一种基于模型的方法，用于对电网集成的季节性存储进行全面的技术经济评估。与文献中介绍的方法相比，该方法具有两个主要优点。第一，我们不对存储设备的运行做出任何假设，包括年度周期，资产利用率或放电深度。而是使用模型来计算最佳存储操作配置文件。其次，基于模型的方法考虑了避免的电力系统成本，这使我们能够估计不同类型的存储设备的成本效益。我们评估了三种特定的存储技术的成本竞争力，包括抽水蓄能，压缩空气和氢气的季节性存储，并探讨了鼓励季节性存储技术提高成本竞争力的条件（成本，存储时间和效率）。这项研究考虑了美国西部的电力系统，其年度能源基础上有24％至61％的可变可再生能源（高达83.5％的可再生能源，包括水力，地热，和生物质能源）。我们的结果表明，对于美国西部的电力系统，预计在不久的将来，抽水持续1天的抽水蓄能和压缩空气蓄能将具有成本竞争力。相反，如果电力和能源容量的资本成本等于或小于1507 kW，则在不远的将来，储氢时间长达1周的储氢可能具有成本效益。到2025年分别为^-1和约1.8 kWh ^-1。但是，根据预计的2050年电力和能源容量的资本成本，预计在未来的电力系统中，长达2周的放电时间的氢存储将具有成本效益。而且，如果更大的可再生能源渗透水平提高了套利或容量价值，实现了可观的能源资本成本降低，或者来自附加服务和新市场的收入（例如可靠性和弹性），则排放持续时间更长的存储系统在不久的将来可能具有成本竞争力。 -获利。