On Saudi Arabia's Red Sea coast, a new city is being built, described as a "new generation of cities" that will be powered entirely by new energy sources. This vision is realized not only by the panels of solar photovoltaic, but also by the "reservoir" and "regulator" of Energy Storage technology. Recently, a Chinese company successfully signed a contract for the Red Sea New City energy storage project, which is the world's largest energy storage project with a capacity of 1,300 MEGAwatt hours. It will help Saudi Arabia build itself into a world-class clean energy center.
New power systems based on wind, solar and other new energy sources are of great significance to green and low-carbon development. However, these energy sources are affected by the weather and have intermittence and volatility, which will lead to the mismatch between peak power generation and peak power consumption, and bring challenges such as insufficient power grid regulation capacity and increased difficulty in frequency stability. The development of energy storage technology can make power supply and demand more balanced, improve the quality of power transmission and distribution, and provide emergency reserve energy. According to a study by the International Energy Agency and the International Renewable Energy Agency, with the rapid expansion of new energy generation, the global demand for energy storage capacity will be 300 to 500 times that of today by 2050. Energy storage is becoming an important part and key supporting technology of new power system.
Energy storage refers to the process of storing and re-releasing energy using physical or chemical methods. At present, energy storage reservoirs, flywheels, chemical battery equipment and compressed air units can be used to "access" electricity as needed. Among them, pumped storage is the most mature energy storage technology with the largest installed capacity. It uses water energy to generate electricity and has a simple working principle, mature technology and long service life, but it is also limited by factors such as location, long construction cycle and large initial investment.
New energy storage technologies represented by electrochemical energy storage and hydrogen energy storage can be widely used in the generation, transmission, distribution and use of new power systems, which is an important development direction in the future. The new energy storage technology can not only "fill in the valley and cut the peak", smooth the power supply and demand, but also has the characteristics of fast response, which can cover the scenarios of energy storage and re-release at the level of seconds, hours, weeks and even months, so as to improve the flexibility of the new power system and ensure the safety and stability of power supply.
Electrochemical energy storage has developed rapidly in recent years, with the global installed capacity increasing from less than 1 gw in 2012 to more than 13 GW in 2020, contributing to the main increase of installed power energy storage in the same period, and Lithium Batteries are the most widely used. Lithium energy storage battery is like a super large "battery", which has great advantages in continuous discharge capacity, response speed and service life, and can be applied in many scenarios such as power generation side, user side and power grid side. Especially in remote areas such as remote mountains and islands, the use of home lithium Battery Energy Storage System can improve the stability and utilization rate of renewable energy generation, achieve "spontaneous self-use" at the user end, and save electricity costs.
Hydrogen storage technology is emerging as a new player in the field of energy storage. Hydrogen is a gas with high energy density and can be stored by electrolysis of water. At present, many countries are studying the use of wind energy, solar energy and other new energy generation, hydrogen production as industrial raw materials, fuel or power generation raw materials, so as to form the "electric-gas-electricity" energy conversion, realize cross-season energy storage and long-distance transmission, support the consumption of new energy electricity.
Many countries around the world are also conducting scientific research and technological development demonstrations on energy storage, including supercapacitors, flywheel energy storage, compressed air energy storage, heat and cold storage. In addition, the large-scale application of energy storage technology still needs to solve a series of problems such as cost and safety. Countries should further accelerate cooperation in basic research and technology, promote the maturity of the energy storage market, accelerate the transformation of the global green and low-carbon power system and energy system, and ensure the early popularization of clean electricity.
