Ⅰ. The principle of the battery energy storage technology
The energy storage technology refers to a series of related technologies that store electrical energy through physical or chemical methods and release it when needed. Generally speaking, it can be classified into mechanical energy storage, electromagnetic energy storage and electrochemical energy storage according to the different ways of storing energy.
The mechanical energy storage can be divided into pumped water energy storage, compressed air energy storage, and flywheel energy storage.
The electromagnetic energy storage mainly includes superconducting magnetic energy storage and supercapacitor energy storage.
The way of electrochemical energy storage is to store and release electrical energy in the form of chemical energy. The current electrochemical energy storage mainly includes batteries and electrochemical capacitors to achieve energy storage. Commonly used battery energy storage includes lead-acid batteries, lead-carbon batteries, sodium-sulfur batteries, liquid sulfur batteries, and high power lithium-ion battery.
The electrochemical energy storage technology has the advantages of high efficiency, application flexibility, and fast response speed, and gradually occupies an increasingly important position in the power storage market.
Ⅱ. The characteristics and main uses of battery energy storage technology
In order to promote the optimization and upgrading of the energy industry and achieve clean and low-carbon development, China has vigorously developed clean energy in recent years. Wind power and photovoltaics have achieved leapfrog development, and the proportion of new energy installed capacity has been increasing.
However, with the rapid development of clean energy, the grid connection of fluctuating and intermittent new energy has brought adverse effects on the power grid in terms of regulation, operation, safety control and many other aspects, greatly limiting the effective use of clean energy.
The PCS battery storage power stations can be combined with distributed/centralized new energy power generation. The energy storage technology is one of the effective ways to solve the problem of new energy power generation grid connection.
With the increasing scale of new energy power generation and the continuous development of battery energy storage technology, it will become a major key technology supporting China’s clean energy development strategy.
As an important way of the energy storage technology, battery energy storage has the power and energy that can be flexibly configured according to different application requirements, has a fast response speed, and is not limited by external conditions such as geographical resources.
The advantages of being suitable for large-scale application and mass production make battery energy storage an irreplaceable position in cooperating with centralized/distributed new energy grid connection and power grid operation assistance.
On the power generation side, the large-scale battery energy storage power station can be used as an independent power station to participate in frequency regulation/voltage regulation of the power grid, provide backup, cut peaks and fill valleys, and can also cooperate with renewable energy storage system to increase renewable energy on-grid electricity.
On the transmission side, it can be used as an alternative to investment and upgrading of the transmission grid, delaying the upgrading of the grid, storing battery energy and providing secondary frequency regulation services for the grid.
On the distribution side, the upgrade and transformation of the distribution network can be delayed, the safety and economy of the operation of the distribution network can be improved, and the ability to accept distributed power sources can be improved. On the user side, price arbitrage can be carried out through the peak-to-valley price difference, and profits can be obtained by participating in demand-side response.