The large-scale development of flywheel energy storage requires both technical improvement and policy support

--Interview with Zou Yu, Deputy Chief Engineer of Nanjing Guodian Nanzi Power Grid Automation Co., Ltd.

The 2024 government work report clearly proposes to develop a new type of energy storage. According to data released by the National Energy Administration, by the end of 2023, China has completed and put into operation new energy storage projects with an installed scale of 31.39 million kilowatts, ranking first in the world. The newly installed capacity in 2023 is about 22.6 million kilowatts, an increase of more than 260% over the end of 2022 and nearly 10 times the final installed scale of the 13th five-year Plan. What are the opportunities and challenges facing the new type of energy storage that steps into the "fast lane"? The new technology route of energy storage is "let a hundred flowers blossom". Can flywheel energy storage take off in the development of new energy storage tide? On March 15, a reporter from Zhongneng Media interviewed Zou Yu, deputy chief engineer of Nanjing Guodian Nanzi Power Grid Automation Co., Ltd. In the field of flywheel energy storage, the company holds the key technology of energy scheduling and control of "flywheel + lithium battery" hybrid energy storage system, and is in a leading position in the domestic industry. Zou Yu said that in the context of the "double carbon" goal, speeding up the research and development and application of energy storage technology can solve the problems of high volatility of renewable energy generation and lack of supporting power supply in the power grid. Flywheel energy storage can meet the needs of short-term high-frequency and instantaneous high-power charge and discharge, and can significantly improve the regulation capacity and operation stability of the new power system. To realize the large-scale development of flywheel energy storage, efforts need to be made in two aspects: technology upgrading and policy support.

Zhongneng Media

"Developing new energy storage" was mentioned for the first time in the government work report. As an industry person, how do you feel? How will the development of new energy storage play a role in promoting the construction of new power systems?

zou Yu

At present, China's energy storage industry ecology has taken shape. Among them, new energy storage has performed well, and the installed capacity has continued to increase. As an important regulatory resource for the new power system, the growth rate is significant. The development of new energy storage plays an important supporting role in absorbing new energy, cutting peaks and filling valleys, enhancing power grid stability, and improving energy and power system regulation capabilities, comprehensive efficiency and safety assurance capabilities.

In the current power system, the main challenges faced by the power generation side include insufficient inertia support capacity, lack of primary frequency modulation resources, weakened secondary frequency modulation capacity, and insufficient voltage support capacity. The main challenges faced by the power consumption side include the large number of distributed power supplies connected, the increasing problems of reverse overload and node overvoltage, which affect the quality of power supply, the impact of load on the power balance of the local power grid, and the difficulty of stable operation of the local power grid. The new energy storage system can realize the flexible adjustment of traditional rigid power systems. It is an important means to solve the problem of power grid stability caused by the access of a high proportion of new energy sources. It is an effective way to ensure the quality of power supply for highly sensitive loads. Therefore, it is imperative to develop new energy storage.

Zhongneng Media

You have been deeply involved in the field of flywheel energy storage technology for a long time. What problems and challenges are still facing the current development of flywheel energy storage in China? What paths will be used to solve it?

zou Yu

In large new energy bases with insufficient supporting power supply, flywheel energy storage with both inertia support capabilities and phase modulation capabilities has broad application prospects. Flywheel energy storage has the advantages of high mechanical inertia, high charge and discharge frequency, large instantaneous charge and discharge power, long cycle life, and good environmental protection. The comprehensive benefits throughout the life cycle are obvious.

However, China still faces three problems in the current development process of flywheel energy storage. One is high costs. The relatively high manufacturing and operating costs of flywheel energy storage limit its large-scale application in the market. The second is technical challenges. Flywheel energy storage technology still has some problems, such as life, energy density and other aspects that need to be further improved. Third, there is insufficient market demand. Due to the special nature of flywheel energy storage, its application fields are limited, resulting in relatively low market demand.

There are three ways to solve these challenges:The first is to reduce the manufacturing and operating costs of flywheel energy storage through technological innovation and optimization of production processes. The second is to strengthen scientific research efforts, overcome key technical problems, and improve performance indicators such as energy density and life of flywheel energy storage. The third is to develop new application scenarios and expand the market demand for flywheel energy storage.

Zhongneng Media

How to balance the safety and economy of flywheel energy storage? Are there any constraints in the current development of flywheel energy storage?

zou Yu

At present, the demand for auxiliary power services is becoming increasingly urgent, the power market is gradually developing and maturing, and the revenue from auxiliary services is showing a growing trend, effectively promoting the market-oriented application of flywheel energy storage. In the next five years, as the scale of the industry gradually expands, the cost of flywheel energy storage is expected to be reduced from the current 3000 yuan/kilowatt to 1,000 - 1,500 yuan/kilowatt.

Taking into account the safety and economy of flywheel energy storage, we can consider the following three aspects. The first is to optimize the design and reduce manufacturing costs and improve safety by improving the structure and materials of the flywheel energy storage. The second is to increase energy density, use new materials and technological innovations to increase the energy density of flywheel energy storage, and reduce unit energy storage costs. The third is to increase the use time of flywheel energy storage equipment and reduce equipment replacement and maintenance costs.

In order to promote the large-scale development of flywheel energy storage, it is also necessary to establish scientific and reasonable market mechanisms and policy support, strengthen industrial chain coordination, and improve the market competitiveness of flywheel energy storage. In the development of flywheel energy storage technology, it is necessary to improve industry standards and regulatory policies. In the next step, we should strengthen research and formulate industry standards for flywheel energy storage, establish a sound regulatory system, standardize market behavior, and guide industry development. At the same time, we actively promote international cooperation and exchange of experience, learn from the successful experiences of other countries, extend the flywheel energy storage industry chain, and further expand application scenarios.

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作者：李东海编辑：张宇校对：孔欣慰