据中国能建官微消息，近日，中国能建与张家口市赤城县签订重力储能一体化项目投资合作意向协议， 赤城县重力储能一体化项目总规划装机容量180MW/1080MWh。
作为全球首个竖井式重力储能工程化应用项目， 赤城县重力储能一体化项目在重力储能领域实现单机功率世界第一、单模块功率世界第一、单体项目装机容量规模世界第一。项目已纳入国家能源局新型储能试点示范项目清单，经电力行业协会鉴定，项目成果为国际领先水平。
赤城县重力储能一体化项目效果图 图源：中国能建
赤城县重力储能一体化项目 由中国能建中电工程、华北电力设计院投资建设，采用竖井式方案， 人工建设竖井构造落差路径，通过重力势能-机械能- 电能的循环转换，实现电能的存储与释放。依托示范项目工程化应用，华北院将在重力储能技术方向通过核心系统和装备研发，形成自主可控的新型重力储能专有技术，实现成套业务、系统集成全产业链竞争优势，在新型储能产业全链条提供技术方案。
重力储能，是通过在有天然或人造高度差的场景中，将液体或者固体重物上升或下降来实现势能存储和释放发电。 充电时，系统根据调控指令，重力轮机将下仓的重物依次提升至位置较高的上仓，将电能转化为重物的势能；放电时，将重物依次下降驱动发电机发电，重物的势能转换为电能。
重力储能基本原理 图源：华北院
重力储能的理论转化效率高于抽水蓄能，同时具有 安全性高、环境友好、适应性强、寿命长、选址约束小、功率和容量易扩展、介质不易损耗、成本相对低、长时储能且无自放电等特点， 系统稳定性和经济性兼顾，对比传统储能系统具有一定竞争优势。

Source of some key parameters for gravity energy storage:North China Institute

According to the different energy storage media and drop realization paths for gravity energy storage, new gravity energy storage can be divided into gravity energy storage based on structure height difference, gravity energy storage based on mountain drop, gravity energy storage based on underground shaft, etc. Technical route.

Typical classification of gravity energy storage

source:North China Institute

Based on structure height difference pattern: The advantages are that site selection is relatively flexible and the expected efficiency is high, but the achievable gap is limited, resulting in high unit investment level and electricity costs, occupying large areas with the same capacity, and the impact of safety accidents is relatively large;

Based on mountain drop pattern: It has the advantages of low investment, stable structure, etc., and a wide range of heavy objects. However, its theoretical efficiency is low, site selection is limited, and its operation is easily influenced by the environment;

Based on underground shaft drop pattern: It can be divided into two categories: using abandoned mines and building new mines. The cost of using abandoned mines is low, the abandoned resources can be reused, and the impact on the environment is small, but it is also limited by different differences in site selection and mine treatment difficulty; new mines have flexible site selection, a safe and stable operating environment, and are subject to restrictions. The investment and efficiency are also relatively good at the same scale and capacity, but the cycle is longer and the engineering technology and equipment technical requirements are also higher.

Gravity energy storage is a very promising type of energy storage with long-term, large-capacity, excellent economy, and network-building characteristics. Construction according to local conditions can effectively fill the gaps in relevant technologies, and is especially suitable for providing large-scale renewable energy for the "Shago Desert" large base. Providing support from large-scale consumption is a new type of energy storage with comprehensive comparative advantages.

responsible editor: Qingyun

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