论文分享丨在长期可再生能源不确定性的情况下,重力储能离网绿色氨系统的灵活设计和运行
论文导读
在长期可再生能源不确定性的情况下,重力储能离网绿色氨系统的灵活设计和运行
Flexible design and operation of off-grid green ammonia systems with gravity energy storage under long-term renewable power uncertainty
背景与意义
氨气是全球最广泛生产和使用的化学品之一,广泛应用于农业、工业和能源领域。然而,传统的氨气生产过程严重依赖化石燃料,导致温室气体排放和资源的枯竭。因此,发展绿色氨气生产技术对于减少碳排放和应对气候变化至关重要。太阳能和风能等可再生能源具有显著的间歇性和波动性,这使得依赖这些能源的绿色氨气生产面临稳定供电的挑战。如何在这种不确定的能源环境下保持氨气生产的连续性和稳定性,是当前研究的热点。
核心研究内容
重力储能系统的引入:本研究首次将重力储能系统(GES)集成到大规模绿色氨气项目中,以确保在有限的灵活操作下为氨气合成反应器提供连续的电力供应。
灵活的氨气合成控制策略:提出了一种离散多稳态灵活控制策略,通过定义离散稳定负载范围和灵活操作间隔,优化了氨气合成的稳定负载操作,平衡了灵活性和稳定性。
长期不确定性建模:开发了基于Copula函数理论和马尔可夫随机过程的长期不确定性场景生成框架,以适应化学生产过程的长期模拟需求。
容量设计和运营调度的协调优化模型:提出了一个非线性模型,并通过分段线性化将其转化为线性版本,以提高绿色氨气系统在可再生能源不确定性下的投资经济效益,并实现系统组件的高效协调。
现实挑战与策略建议
现有的氨气合成过程相对刚性,难以适应风能和光伏电力的间歇性和波动性。此外,可再生能源输出的不确定性和相关性也给系统规划和运营带来了挑战。通过引入重力储能系统和灵活的氨气合成控制策略,可以显著增强系统对可再生能源波动的适应性,提高系统的经济性和安全性。此外,采用长短期不确定性建模和协调优化模型,可以进一步优化系统的设计和运营。
延伸思考
若考虑锂电池循环寿命与成本下降趋势,在何种电价/设备成本条件下重力储能仍是更优选择?地理条件(如可用落差)是否可能成为部署瓶颈?
重力储能如何通过充放电时间与功率的灵活性,弥补电解槽与氨合成单元的动静特性差异?其对系统稳定性的提升表现在哪些环节?
Haber-Bosch工艺的"多稳态"设计如何在设备启停成本与调节响应速度间平衡?相比连续调节策略,其效率折损与可靠性提升是否具备经济性优势?
从电力生产到氨合成的全链条中,系统是否涵盖氢泄露、催化剂更换的间接排放?其碳足迹是否满足国际绿氨认证的并网/离网标准差异?
论文脑图
论文简介
Abstract: The conventional ammonia production process heavily depends on fossil fuels, making it urgent to redesign the synthesis process to reduce greenhouse gas emissions and address the challenges of depleting resources. Off-grid ammonia synthesis powered by renewable energy offers a feasible pathway to producing carbon-free ammonia. However, a significant challenge for off-grid green ammonia plants is ensuring the reliable operation of the relatively inflexible ammonia synthesis units under intermittent and unpredictable wind and photovoltaic power conditions. To address this challenge, this study proposes a novel off-grid green ammonia system and a discrete multi-stable flexible control strategy for ammonia synthesis. For the first time, gravity energy storage is integrated into a large-scale green ammonia project to ensure a continuous power supply to the ammonia synthesis reactor under limited flexible operation. The optimal design and operation of the proposed system are modeled as a mixed-integer nonlinear problem, which is reformulated into a linear version through piecewise linearization. Additionally, the stochastic nature of renewable energy generation is fully considered. A scenario generation framework based on Copula function theory and Markov stochastic processes is developed to accommodate the long-term simulation needs of chemical production. The effectiveness of the proposed method is validated through a case study. A sensitivity evaluation is also carried out to analyze the impact of wind and photovoltaic power configurations, load adjustment periods, and system component costs on system revenue and module capacity. This study provides new insights into the system configuration and flexible operation of green ammonia systems and is expected to guide the construction and operation of practical green ammonia plants.
Highlights:
Integrating gravity energy storage into green ammonia systems for the first time.
Discrete multistable flexible control for Haber-Bosch with engineering feasibility.
Long-term uncertainty modeling for wind-solar power using the Copula-Markov method.
A coordination optimization model for capacity design and operational scheduling.
Flexible control reduces LCOA by 102 $/t and decreases power curtailment by 15.01 %.
Graphical abstract

原文链接
https://www.sciencedirect.com/science/article/abs/pii/S0306261925003599
引文信息
Jiahui Zhou, Bing Tong, Haiming Wang, et al.Flexible design and operation of off-grid green ammonia systems with gravity energy storage under long-term renewable power uncertainty[J].Applied Energy,2025,388:125629.
DOI:10.1016/j.apenergy.2025.125629.
本文来源:《南方能源建设》