Due to the significant intermittency, volatility and randomness of new energy sources such as photovoltaics and wind power, if a high proportion is connected to the power grid system, it will have a significant impact on the stability of the power grid. At this time, if the energy storage system is used for charging and discharging to adjust the gap between the power supply and the grid load, the matching of power consumption and power generation can be achieved.
That is to say, the energy storage system can provide various services such as peak regulation and demand response for the operation of the power grid, effectively realize the peak shaving and valley filling of the power grid, relieve the pressure of peak power supply, promote the consumption of new energy, and provide new opportunities for the safe and stable operation of the power grid. way.
With the maturity of energy storage technology and the decline in cost, the energy storage market will start to grow rapidly from 2021. In 2021, the global demand for electrochemical energy storage related to lithium batteries is about 35GWh, of which the domestic demand is about 5GWh and the overseas market is about 30GWh, a year-on-year increase of 227%. According to the statistics of Essence Securities, among the overseas energy storage market, the United States has the highest proportion, about 15GWh in 2021, mainly due to the large-scale application of Texas and California on the grid side; followed by China, about 5GWh, the main driving force in my country is power supply Side new energy supporting and industrial and commercial starting capacity.
Source: Essence Securities
Reasons for the explosion of the energy storage market
At present, both the domestic market and the overseas market, the energy storage industry has shown a doubling of growth. The reason is that there are some differences between the overseas market and the domestic market.
As far as overseas markets are concerned, mainly represented by Europe, a very important driving factor is that the Russian-Ukrainian war has led to a surge in local electricity prices, which has driven the demand for household energy storage. Overall out of stock status. According to industry sources, if you place an order now to buy a household energy storage system, you will basically not get the goods until March next year.
The second is the education of consumers. After seeing other neighbors buying them, many consumers feel that it is easy to use and affordable, and they also start to buy household energy storage products. The current penetration rate of household energy storage systems in Europe is about 3%, showing a clear growth trend. According to media reports, the installed capacity of household energy storage systems in Europe last year was about 1.9GWh. This year, if the shortage of installation workers is not considered, the installed capacity can reach 5~6GWh. Due to the long training cycle of qualified electricians in Europe, such as a vocational training in Germany, it takes 2 to 3 years from start to qualification. Therefore, the current shortage of installation workers also limits the installed capacity of household energy storage. .
Domestically speaking, energy storage is still mainly based on industrial and commercial energy storage, and household energy storage has not yet developed. The main driving factor for the growth of the domestic energy storage market is economics, and independent shared energy storage has mobilized the enthusiasm of investors. It used to be energy storage on the power generation side, supporting wind and solar power plants, and it was a mandatory construction. At that time, many of them were shoddy and difficult to market, but now independent shared energy storage has begun to emerge and has become a new business model.
This is mainly because in early June, the National Development and Reform Commission and others issued a notice on “Further Promote the Participation of New Energy Storage in the Electricity Market and Dispatching Application”, further clarifying the positioning of the new energy storage market, and establishing and improving relevant market mechanisms, price mechanisms and operation mechanisms. The notice has three main measures to stimulate investors’ enthusiasm for investment. The first is to give energy storage an independent status and to participate in the power market as an independent subject. That is to say, independent energy storage can obtain benefits from three aspects of spot market node electricity price difference, lease fee and capacity electricity price; For power transmission from the power grid, the corresponding charging power does not bear the transmission and distribution price and government funds and surcharges, which will allow the energy storage power station to obtain a discount of 1-2 cents per degree in electricity price; the third is to encourage the exploration of the same energy storage main body can be based on part of the electricity price discount. A market model that simultaneously participates in two modes of capacity independence and partial capacity union.
These new policies have boosted the enthusiasm and enthusiasm of investors and the development of the domestic energy storage market. According to the data of the Energy Storage Application Branch of the China Chemical and Physical Power Industry Association, a total of 66 energy storage projects were connected to the grid and put into operation in the first half of 2022, including 51 electrochemical energy storage projects and 12 pumped storage projects. The number increased by 37.5% year-on-year. From a quarterly perspective, 37 electrochemical energy storage projects were connected to the grid in 22Q2, an increase of 164.3% compared with the first quarter. There was a big improvement in the quarter, with a month-on-month increase of 573.37%.
Energy storage industry chain situation
The application mode of energy storage is very extensive. At present, energy storage on the power generation side accounts for a relatively high proportion, mainly installed along with large-scale ground power stations. However, the development of household energy storage has been very fast in recent years, and many photovoltaic Integrated equipment with energy storage, that is, an all-in-one installation. Generally speaking, a household solar energy storage system mainly includes multiple parts such as cells, energy storage inverters (bidirectional converters), and component systems.
A typical system is generally 5kW (component + inverter), supporting a 10kWh energy storage battery, or 10kW+10kWh, of which the battery is the core of the energy storage system, accounting for 45% to 50% of the cost; energy storage inverter Charge and discharge can be controlled, and AC and DC conversion can be performed, and the cost accounts for 10% to 15%; the component system, that is, the photovoltaic system used for solar power generation, accounts for 20% to 25% of the cost; the installation cost will increase from 10,000 in 2021. To about 20,000, accounting for 15% to 20%.
Household energy storage system products generally include two types: integrated machine and split type. Among them, the all-in-one machine is an integrated all-in-one machine system with photovoltaic inverter, energy storage battery and controller placed inside. The working status can be displayed conveniently, quickly and intuitively through the touch screen, and various working modes can be realized by modifying the parameters, which is easy to use. Generally speaking, there are three working modes: solar energy priority mode, AC priority mode, and SE priority mode (off-peak power consumption mode).
The household split system is to install the inverter and the battery system separately. Users can match the household energy storage inverter according to their own needs, and can also match the switching power supply or the inverter as a backup power supply. Generally, there are four types of hybrid home photovoltaic + energy storage systems, coupled home photovoltaic + energy storage systems, off-grid home photovoltaic + energy storage systems, and photovoltaic energy storage energy management systems.
As far as the technical route is concerned, the mainstream technical route of household energy storage is mainly lithium iron phosphate batteries, and sodium ion and lithium iron manganese batteries may be used in the future. This is mainly because household energy storage pays more attention to safety and long cycle life, and is not so sensitive to cost and price. The lithium iron phosphate battery has the characteristics of higher safety and long cycle life, which is more in line with the needs of energy storage batteries than ternary lithium batteries, and has become the mainstream development route of energy storage batteries. Tesla and LG’s energy storage The battery has also gradually shifted from the ternary route to the lithium iron phosphate route.
The energy storage inverter is also a component with a relatively high cost in the household energy storage system. Generally speaking, if the power is the same, the price of the energy storage inverter will be twice that of the photovoltaic inverter. As for related companies, companies that used to make string inverters basically have the technical reserves of energy storage inverters. Currently, Jinlang Technology, GoodWe, Deye and Sungrow all have energy storage inverters in shipments. .
For household energy storage, it is necessary to assemble the inverter and the battery system for use, so how to better adapt the inverter and the battery system is critical. Many dealers now sell inverters and batteries separately. Therefore, when dealers and installers assemble themselves, they need to ensure the compatibility of batteries and inverters. The needs of their own terminals match, because different countries have different needs for terminal products. For example, Germany prefers energy storage above 10kWh, and France and Italy prefer energy storage within 10kWh. High-end users in Europe and the United States care more about human-computer interaction and so on. Therefore, it is necessary to ensure that the BMS in the energy storage system is better adapted to the energy storage inverter. For example, it needs to be adapted to the energy storage inverter. The energy storage inverter controller communicates with the BMS through the CAN interface to obtain the battery pack. Status information, which can realize the protective charging and discharging of the battery and ensure the safe operation of the battery.
Epilogue
In recent years, both domestic and overseas, the demand for energy storage has been growing rapidly, which will drive the demand for related upstream industry chains. With the current slump in consumer electronics, the energy storage market may be able to open a door for semiconductor manufacturers. new door.