Views: 0 Author: Site Editor Publish Time: 2023-07-18 Origin: Site
The domestic large-scale market has experienced rapid development, with several energy storage brands increasing their shipments by leveraging domestic channel resources. In 2021, Chinese energy storage shipments were led by CATL. Energy storage PCS shipments have also grown rapidly.
Furthermore, more and more new technologies have emerged, contributing to the sustainable development of the energy storage industry. High-voltage energy offers significant advantages in large-capacity scenarios. Fire storage power stations have faced frequent fires, leading to an emphasis on energy storage safety in policies. Liquid cooling and whole fluorine ketone solutions have garnered attention. New electrochemical energy storage technologies, such as sodium-ion battery storage, liquid flow battery energy storage, and hydrogen storage, have rapidly industrialized. New physical energy storage technologies, such as light and heat storage, gravity energy storage, compressed air storage, and flywheel energy storage, are gradually being implemented through demonstration projects.
The energy storage industry chain includes various links:
Energy storage system: This encompasses batteries, PCS, BMS, EMS, and other components. Key players in this area include CATL, EVE Lithium Energy, Sunshine Power, Nandu Power, Kesta, Kehua Data, BYD, Sunshine Power, Jinlang Technology, and others that have a significant overseas presence.
Engineering EPC, grid-connected detection, and post-operation and maintenance: Notable companies in this segment include South China Technology, Ates, Linyang Energy, Baoguan
The energy storage battery material system primarily revolves around lithium iron phosphate, and batteries are evolving towards larger capacities.
According to the requirements set by the Ministry of Industry and Information Technology, the energy density of energy storage batteries should be ≥145Wh/kg, and the energy density of battery packs should be ≥110Wh/kg. The cycle life should be ≥5,000 times, and the capacity maintenance rate should be ≥80%. Electrochemical energy storage, especially lithium battery energy storage technology, is undergoing a new transformation cycle. New technologies and features such as large batteries, high voltage, and water cooling/liquid cooling are gradually emerging. Additionally, sodium-ion batteries may gain a competitive advantage in the future due to their cost-effectiveness.
Chinese manufacturers lead the global energy storage battery cell shipments, with CATL being the world's top supplier. It is estimated that global energy storage battery shipments in 2021 amounted to 59.9GWh, with Ningde Times accounting for 16.7GWh, or 27.9% of the total. Paineng Technology shipped 1.5GWh, accounting for 2.6%. Shipments are expected to reach 114.9GWh in 2022, a 91.9% increase, with Ningde Times accounting for 45.0GWh, or 169.5%. According to calculations, it is projected that global energy storage battery shipments will reach 122.5/219.6GWh in 2022-2023, representing a 101%/79% increase. Ningde Times is expected to occupy 50/100GWh of the shipments, reflecting a 199%/100% increase, and maintaining a leading position.
In the realm of inverter technology, the trend is moving towards DC 1500V architecture, replacing the traditional 1000V architecture, especially in power stations. In 2021, approximately 49.4% of domestic photovoltaic installations operated at the DC voltage level, while the 1000V market accounted for 50.6%. Distributed photovoltaic systems still predominantly utilize the 1000V voltage level. For instance, all residential systems use the 1000V-level system, while 80% of industrial and commercial systems employ the 1000V level.
The 1500V energy storage system exhibits significant advantages. The core product of the 1500V system is the 1500V energy storage PCS. Compared to previous systems, the 1500V energy storage system offers a 35%+ increase in energy density and power density, a 5%+ reduction in system cost, and a 0.3%+ increase in system efficiency. With a 40-foot container and a 280AH battery, the maximum installed capacity for a 1000V battery is 3.3MWh, while the 1500V system can achieve 4.5MWh. Besides reducing costs associated with PCS, batteries, and auxiliary accessories, labor, foundation, and land costs also decrease significantly. Recent large-scale projects have seen the 1500V penetration rate surpass two-thirds. Representative manufacturers in this area include Sunshine, Shangneng, and Kehua, with Shangneng Electric securing a 500 MW-level energy storage project in Shandong using 1500V PCS.
The application of inverter technology is constantly evolving, and group PCS is being increasingly implemented on a large scale. Group PCS addresses the limitations of centralized PCS systems and enables large-scale applications. The current battery energy storage systems primarily employ centralized PCS, which can lead to imbalances between battery clusters and potential underutilization of some batteries. Group string PCS allows for cluster-level management, enhances system lifespan, improves the discharge capacity throughout the entire lifecycle, and exhibits a growing trend in large-scale applications. The Huaneng Huangtai 100MW/200MWH project is the first large-scale energy storage power station in China to adopt a series of PCS architecture. Similarly, the 3MW/6MWH project in Texas, Shandong, also utilizes this system architecture.
Guodian Investment Oil City Daqing implemented a 200MW Optical Storage Experimental Platform. Shangneng Electric provided various model inverters, including 230kW group string inverters, dozens of 225kW and 175kW group string inverters, 3.125MW centralized all-in-one machines, and 3.15MW distributed all-in-one machines. The 250kW group string inverter, in particular, revolutionized the traditional decentralized installation approach. With a 1MW integrated platform and centralized operation and maintenance management model, it significantly reduced time and manpower requirements while improving operational efficiency.
Integrating digital information technology with photovoltaic and energy storage technologies, a new concept of forming, intelligent, and modular design of energy storage systems has emerged. This approach allows for refined management at the battery module level, resulting in increased discharge, reduced battery configuration by 13%, improved battery life by 50%, better investment with a 30% reduction in initial configuration, minimalist operation and maintenance (reducing transportation and maintenance costs by 50 million yuan over 25 years), increased safety and stability (achieving a 99% to 99% reliability rate), and an overall reduction of more than 20% in levelized cost of storage (LCOS). This design also aids the transition from photovoltaic parity to energy storage parity.
One disadvantage is that the current cost of PCS is relatively high, but there is ample room for price reduction. Representative manufacturers in this field include Huawei, Shangneng, and Shenghong.
In terms of electrical topological structure, high-voltage-level joint plans offer significant advantages for large-capacity energy storage systems.
As the capacity of energy storage integrated systems increases, the traditional series rising voltage scheme faces several challenges. Firstly, large capacities require a high number of batteries, which increases safety risks. Secondly, as the number of battery cycles increases, the performance consistency among individual cells gradually declines. These factors collectively limit the single-machine capacity of the system. Additionally, as parallel equipment increases, secondary communication and coordination control become more complex.
The advantages of high-voltage-level joint plans for large-capacity systems lie in their parallel combination of multiple energy storage units. Each energy storage unit outputs dozens to hundreds of volts, providing a wide voltage range for discrete battery stacking. This reduces the volume of the battery stack and the number of batteries required, significantly increasing system capacity while improving safety.
Currently, domestic companies with high-voltage-level technology include Guodian Nanrui, Jinpan Technology, Zhiguang Electric, Sifang Co., Ltd., and New Scenery. These companies have published and received orders worth 135 million yuan.
In recent years, there have been frequent fires in energy storage power stations, highlighting the importance of temperature control, heat management, and fire protection in energy storage systems. Industry policies have been implemented to address these concerns, leading to the accelerated development of energy storage and fire protection systems. Metal lithium, present in lithium-ion batteries, exhibits high reactivity and has raised safety concerns for the use of lithium batteries in energy storage. Incomplete statistics show that over 17 energy storage incidents occurred worldwide in 2022. The country has introduced policies related to energy storage and fire safety since 2021, emphasizing the importance of fire protection under new standards.
In the field of energy storage system integration, various modes coexist, and there are many players involved in system integration. There are three main modes currently:
Entire industry chain layout: Companies involved in battery, PCS, BMS, EMS production, such as BYD, represent this mode domestically.
Professional integration: This mode involves integrators that procure components externally and specialize in system integration. It has fewer applications domestically but is represented by foreign companies like DOOSAN and IHI.
Transformation from equipment suppliers to system integrators: This mode is widely applied domestically. Companies that previously focused on specific products, such as photovoltaic inverter manufacturers like Jinlang Technology, Gudewei, and Deye Technology, power battery energy storage manufacturers like Energy, Penghui Energy, and manufacturers of PCS/BMS/EMS such as Jinpan Technology, Cosmald, Ke Shida, Kesta, KOCS, China Data, Baoguang Co., Ltd., Kelu Electronics, have transformed into system integrators. In the US market, mainstream integrated manufacturers can be found operating in all three models.
Sodium-ion batteries: The business process for sodium-ion batteries is accelerating. Sodium batteries offer better performance than lithium batteries at a more cost-effective price due to the abundance of sodium resources. Sodium batteries exhibit fast charging performance (reaching 80% power in 15 minutes at room temperature), good performance in low-temperature conditions, a cycle life of 4,000-5,000 times under normal temperature conditions, and an energy density comparable to that of iron-lithium batteries. While the world's proven lithium resources in 2022 amounted to about 89 million tons, with over half of them distributed in South America, China possesses 5.1 million tons, representing only 6% of the global proportion. Moreover, 65% of lithium raw materials require imports. In contrast, sodium resources are abundant and widely distributed worldwide, with sodium chloride-rich seawater.
Flow batteries: Liquid flow batteries, where the positive and negative electrolytes are separated, offer excellent performance. Iron-chromium and full-scale flow batteries are two major commercial directions in this field.
Light thermal energy storage: Light thermal power generation possesses a natural advantage as an energy storage method, especially for peak adjustment and frequency regulation.
Gravity energy storage: Gravity energy storage is a mechanical energy storage method that utilizes the potential energy from a height difference to facilitate charging and discharging processes.
Compressed air storage: Compressed air energy storage involves compressing air during periods of low power demand and storing it in high-pressure vessels, such as abandoned mines, gas storage tanks, caves, expired oil and gas wells, or newly constructed gas wells. Compared to storing air in pressure vessels like steel cans, utilizing underground spaces such as salt caverns for constructing high-capacity power stations significantly reduces raw material and land costs. Compressed air storage systems can be classified as traditional systems (requiring replenishment), systems with heat storage devices, and liquid/gas compressed energy storage systems, based on working medium, storage medium, and thermal source.
Flywheel energy storage: Flywheel energy storage is a new technology that is still in the early stages of commercialization. It utilizes a rotating flywheel to store and release energy.