The existing energy storage system is divided into five categories: mechanical energy storage, electrical energy storage, electrochemical energy storage, thermal storage and chemical energy storage. At present, the highest proportion of the world is pumping capacity, Energy Storage Systems the total installed capacity of the scale reached 127GW, accounting for 99% of the total storage capacity, followed by compressed air storage, the total installed capacity of 440MW, ranked third is the sodium sulfur battery , The total capacity of the scale of 316MW.
Energy storage can be used in different parts of the power system, Energy Storage Systems the overall role is to achieve new energy power Internet, to maintain efficient and safe operation of electricity and power supply and demand balance. For different aspects, the role of energy storage are different: ① large-scale new energy power generation links, energy storage system is conducive to cutting peak filling valley, Energy Storage Systems so that unstable power smooth output; energy storage system through the power conversion device, Reactive power throughput, to maintain the balance of the system instantaneous power to maintain the system voltage, frequency and power stability, improve power supply reliability. ② In the conventional energy generation link, the energy storage system can replace some of the expensive peaking unit, to achieve the function of peaking, but also to be forced to participate in peaking the base load unit, improve system efficiency. ③ in the transmission and distribution links, Energy Storage Systems energy storage system can play a peak load and improve the role of power grid performance. In the power grid links to set the appropriate size of the energy storage station, can enhance the impact capacity of the power grid to improve the degree of mediation, better balance of supply and demand. (4) The energy storage system installed in the end user can improve the reliability of the power supply through the power storage, especially in the event of an unexpected power failure. Energy Storage Systems The demand side management can be carried out in the time- Electricity "to buy electricity to fill the energy storage equipment, in the high price" peak power "time to release energy storage equipment in the power, to achieve both the cost of saving electricity users, but also peak load filling, smooth electricity load, in a certain The degree can ease the pressure of the grid regulation. Conventional end users are only consumers of electricity, and with the promotion of distributed energy systems, future end users are also suppliers of electricity, there is a two-way energy flow between users and power grids. When the end user has the remaining power of the Internet, Energy Storage Systems there will be large-scale new energy generating units of the power fluctuations, therefore, set up in the end user's energy storage system will also play a distributed power supply power quality, smooth output and so on.
In general, there are three types of functions corresponding to different applications: ① improve the power quality; ② provide bridge power; ③ energy management. Improve the power quality, including maintaining the system transient stability and frequency, voltage regulation, Energy Storage Systems such functions require energy storage equipment rapid response (within 1s), the energy storage equipment discharge duration (energy dimension) requirements in the order of minutes. The provision of bridging power refers to the ability to provide transitional power during the conversion process of power loss or between different sources of power. Energy Storage Systems The application is power emergency reserve, variable load, power system failure, etc., which require the response time of energy storage equipment In seconds to minutes, the duration of the discharge can be as long as the order of hours. Energy management corresponds to a long period of energy transfer, applications include grid peak filling valley, end-user power management, etc., the function of the discharge duration of the requirements of up to several hours.
Energy storage system has three specific functions: to improve power quality, to provide bridge power, energy management. Power storage technology has pumped storage technology, Energy Storage Systems compressed air storage technology, superconducting energy storage technology, super capacitor energy storage technology, electrochemical energy storage technology, composite energy storage technology. The development of energy storage industry in China to make the following recommendations: from the macro-level development of energy storage development plan; the introduction of energy-saving technology in the industrialization of incentives and mechanisms; issued energy-related technical standards and management standards, the establishment of energy storage device recycling management mechanism ; To strengthen energy storage technology research and development and demonstration; the establishment of energy storage industry chain, reduce costs; explore and optimize the business model, to speed up the pace of energy storage technology market.