In the future, large-scale long-term energy storage will become a rigid demand

A few days ago, the People's Government of Inner Mongolia Autonomous Region issued the "Implementation Opinions on Accelerating the Development of New Energy Storage". The document proposes that by 2025, new energy storage will be transformed from the initial stage of commercialization to large-scale development. The installed scale of new grid-connected energy storage capacity will reach more than 5 million kilowatts. For new market-oriented grid-connected new energy projects, in principle, the scale of energy storage is not less than 15% of the installed capacity of new energy projects, and the energy storage time is more than 4 hours. The allocation ratio will be adjusted in time according to the situation after 2022. This number is required to be higher than previous figures released by the provinces. In the past, most of the energy storage time was required to be 2 hours.

The success of the implementation of the new energy storage in Inner Mongolia will directly affect the effective implementation of the integration of source, network, load and storage and the implementation of multi-energy complementarity. Zhang Huamin from the Dalian Institute of Chemical Physics, Chinese Academy of Sciences put forward his insights on long-term energy storage.

Long-term energy storage is the key core technology of new energy storage systems

In 2021, the U.S. Department of Energy released a report supporting long-term energy storage, defining long-term energy storage as at least 10 hours of continuous operation (discharge) and a service life of 15 to 20 years. In November 2021, at the United Nations Climate Change Summit in Glasgow, Scotland, executives from 25 energy and technology companies, including BP, Siemens Energy, Highview Power, and Form Energy, established a long-term energy storage council. meeting. The council aims to educate and educate businesses, governments and utilities on long-duration energy storage technologies, and to create incentives to support large-scale deployment of long-duration energy storage systems.

The deployment of long-duration energy storage systems is likely to accelerate in the coming years, especially as countries continue to expand renewable energy deployments, according to a recent survey report prepared by the Long-Duration Energy Storage Council in partnership with McKinsey & Company. Long-duration energy storage will be the "lowest cost flexibility solution" once renewables reach 60 to 70 percent of the electricity system's market share.

Zhang Huamin said that as of the end of October 2021, the cumulative installed capacity of renewable energy power generation in my country reached 1.002 billion kilowatts, breaking the 1 billion kilowatt mark, doubling from the end of 2015, accounting for 43.5% of the country's total installed power generation capacity. To achieve the carbon peaking goal in 2030, it is expected that by 2030, the total installed capacity of renewable energy power generation will reach more than 60%, surpassing thermal power to become the absolute main power source.

At that time, in case of windless weather or continuous rainy weather, since the installed capacity of thermal power plants is greatly reduced, to ensure the safe and stable power supply of the new power system, it is necessary for long-term energy storage power stations to provide the power required by the grid load.

Therefore, long-term energy storage is the key core technology for building a new energy storage system of "new energy + energy storage" and realizing the "dual carbon" goal, which must be highly valued. While accelerating the deployment of renewable energy power generation capacity, China should simultaneously deploy long-term energy storage systems to meet the needs of establishing a new power system of "new energy + energy storage".

There is a gap between my country's long-term energy storage and advanced countries

In the "14th Five-Year" energy storage major project deployed by the Ministry of Science and Technology, it is proposed to research and develop "4-hour energy storage technology". Zhang Huamin said: only focus on lithium-ion battery energy storage technology, plus the safety of lithium-ion batteries, etc. The problem is far from meeting the needs of achieving the "dual carbon" goal.

The "Implementation Opinions" of the Inner Mongolia Autonomous Region, starting from the actual needs of building a new energy storage system of "new energy + energy storage", is the first in the country to propose "the energy storage duration is more than 4 hours; the allocation ratio will be based on the The situation should be adjusted in time.” Although the energy storage market still has a certain gap from the “International Long-term Energy Storage Council” and the long-term energy storage requirements of developed countries, it is clearly pointed out that the allocation ratio will be adjusted in time according to the situation after 2022. It will guide the development direction of my country's energy storage technology.

90% of the installed capacity of electrochemical energy storage in my country is lithium-ion battery technology, but the current lithium-ion battery energy storage technology is difficult to meet the demand for long-term energy storage of the new energy storage system of "new energy + energy storage". Therefore, continue to deploy and support research and development and engineering applications of high-safety, long-term technologies with a service life of greater than 15 years, and environmental friendliness.

After 2030, in my country's new power system, the proportion of renewable energy will be greatly increased, and the proportion of thermal power generation will be greatly reduced. In cloudy and rainy days, the power generation of solar cells will be greatly reduced. To ensure the safe and stable power supply of the power system, a high-power, long-term energy storage system is required to play a role.

In order to dig deep into the economics of large-scale long-term energy storage projects, Zhang Huamin believes that adding energy storage systems to the power grid, whether it is on the grid side, power supply side or user side, requires increased investment, just like doing environmental protection back then, it needs to increase cost. First of all, energy storage equipment manufacturers should increase investment in research and development to develop energy storage equipment with high safety, high cost performance in the life cycle, and environmental friendliness (including harmless disposal of batteries after they are scrapped), so as to reduce equipment costs.

On the other hand, since energy storage is a major demand for the country to achieve the "dual carbon" goal, the country should formulate an effective price compensation mechanism and corresponding long-term energy storage just like the development of new energy vehicles, solar cells and other industries. Industrial policies, such as the two electricity price policies for pumped energy storage, promote the healthy development of the long-term energy storage industry, and allow energy storage technology to escort the establishment of a new power system and the realization of the "dual carbon" goal.

In addition, the state should focus on supporting the comprehensive energy conversion efficiency in response to standard pumped hydro storage. The comprehensive energy conversion efficiency should be greater than 70% and the service life should be greater than 15 years. When considering the cost of long-term energy storage systems, it must include the harmless treatment after the battery is scrapped processing costs.