In 2017, the energy storage policy continued to respond favorably to the policy. At the same time, the strong demand for the electric vehicle market drove down the price of the power battery. Even so, the battery storage market in China has not seen much improvement.
Looking at the global battery energy storage market, the United Kingdom continues to maintain a strong momentum of development and leads the world; the United States, Australia, and South Korea have 100 MW-level energy storage projects; Europe, Japan, India, the Middle East and other regions of various commercial energy storage demonstration projects Have appeared.
With regard to battery energy storage, I would like to talk about a few points:
First, battery storage status
From the external point of view, China is a big energy importer, with 60% of primary energy relying on imports. This poses a great risk to the energy security strategy. From an internal point of view, coal power consumption accounts for more than 60% of the total power supply structure in China. (Before 2016), improving energy structure, actively developing new energy, and clean green energy are undoubtedly a top priority.
Wind power and solar energy are the absolute main power for new energy generation, but they all have features such as large fluctuations and difficulties in forecasting. Battery storage has the characteristics of quick dispatching response, flexible configuration, precise control, and environmental friendliness. It has become the best partner for new energy generation. This is an industry consensus and has been recognized by the relevant national authorities.
Although gas-fired power generation and pumped storage power stations can also complete part of the new energy peaking work, the smooth output and frequency modulation effects are far lower than those of battery storage. Wind power and photovoltaic power generation concentrated in the same place can naturally balance a part of the output fluctuations (such as wind and solar complementarity), but the moment when there is neither wind nor light will occur from time to time, so supporting a certain scale of battery energy storage power stations is new. Energy power plants realize the ultimate choice for tracking planned power generation.
According to the prediction of the national authoritative department, by 2030, the installed capacity of wind power generation in China will reach 833 million kilowatts. Assume that the energy storage capacity will be 2%, and the new energy generation will use at least 16 million kilowatts of power storage capacity.
There are many types of energy storage power stations that are matched with new energy power generation, such as light storage, wind storage, and scenery storage. From the aspects of use effect, utilization efficiency, convenient dispatch, and business model, the author thinks that it is a hundred trillion. Independent energy storage plants above the scale of watts will occupy the mainstream position.
Second, the value of battery energy storage
Battery energy storage has both economic value and more social value (values other than economic value). From some perspectives, its social value far exceeds its economic value, such as its military value, its value of electricity security, and its strategic value of energy. Wait. Only from the economic value, mainly depends on the size and use of occasions, such as charging treasure can only solve one or two mobile phone users a day of mobile use problems; household energy storage or emergency power storage power supply, can only solve a household Part of the electricity or temporary power outage problems; user-side energy storage usually only consider the use of peak-to-valley electricity price cuts to fill the valley and demand side response and other issues.
The above listed energy storage applications have relatively long or no economic payback periods, and even certain investment risks exist (for example, the user side energy storage may increase the estimated payback period because the peak-to-valley difference is smaller).
In contrast, large-scale energy storage (above 100 MWh) is characterized by rapid response, precise control, and bi-directional regulation. If it can be used by grid dispatch, it is of great social value in the field of grid security strategies such as frequency modulation and peak shaving. Favorable (mainly FM service fees, capacity service fees, etc.), however, the premise is that there should be an open electricity market (including the electricity auxiliary service market).
Third, the main battlefield of future battery storage
Although the new energy microgrid, distributed photovoltaic generation, and user-side peaking (peak load shifting) will all use energy storage technology, I believe that the large-scale application of battery energy storage will be the transmission and distribution side of the grid. Large-scale, independent battery-storage power stations that can be directly dispatched by the power grid on a scale of more than 100 megawatts can not only ensure the power supply security of the power grid, but also improve the quality of power in local areas. Battery energy storage even subverts traditional grid design concepts and Design rules, improve equipment utilization, reduce waste of resources, delay the expansion of the construction cycle.
With the gradual liberalization of the electricity market in the future, the power spot trading and power assisted service market will certainly lead to the birth of a large number of energy storage power stations.
Fourth, the main barriers to large-scale battery energy storage applications
In the past two years, at some meetings, we often heard some remarks such as "energy storage technology is not enough," "battery costs are too high," and this is far from our current understanding of energy storage.
Mechanistically speaking, battery energy storage technology and electric vehicle technology are the same. Taking BYD Electric Vehicle and battery energy storage as examples, the same power battery is used. The battery management system (BMS) and the converter system (PCS) also basically use the same technology and products. An electric vehicle is a small mobile storage device. Energy station. One obvious fact is that in recent years, our national electric vehicle market has developed rapidly, and many mature technologies have been at the leading international level.
Due to the rapid increase in the size of the electric vehicle market, the price of power batteries has also declined year by year. It is estimated that the price of lithium iron phosphate batteries for energy storage will reach RMB 1 per watt-hour in 2018. Calculated at this price, the overall cost of the 2-hour lithium iron phosphate battery storage power station has already fallen to below the level of 1/2 of the pumped storage power station (the current cost of the pumping station is about 6,000 yuan). Under standard conditions (room temperature 25±5 degrees Celsius, charge/discharge rate 0.5C, 95% DOD), the cycle life of lithium iron phosphate battery can reach more than 8000 times (more than 70% of the remaining capacity). According to this calculation, the cost of electricity for a 2-hour lithium iron phosphate system is about 0.25 yuan, which is equivalent to the cost of thermal power.
The above calculation is only one of the reference methods to measure the economic value of battery energy storage. The value of energy storage is reflected in the fact that although the battery energy storage system itself cannot generate electricity, battery energy storage is of great significance in the transmission, transmission, distribution, and use of power grids, and it needs to be gradually recognized and discovered.