Can I store it?

This summer, Sichuan has continued to be high -temperature, and the tension of power supply and demand has further intensified. In everyone's impression, Sichuan has rich water resources, with multiple giant hydropower stations, hydropower installed capacity and power generation. Why are there a power gap in the summer?

This year's extremely high -temperature drought is the most important reason. The severe high temperature and drought disaster weather makes Sichuan face the highest extreme high temperature in the same period, the minimum precipitation in history, and the highest power load of the same period of the same period.

Source: Veer Gallery

PART.1

The world of modern people is inseparable from electricity

As the basis of the operation of modern society, electrical energy is widely used in various fields of production and life. Power stations convert the energy of chemical energy stored in wind energy, water energy, and coal to power energy, and use the grid to transmit them to millions of households. For example, the electricity produced by the far power plant in the distance is transmitted to your home. You can use electricity to light up (electric energy converted into light energy), cook (electric energy converted into heat energy), and washing clothes (electrical energy converted into mechanical energy).

Image source: References 1

The current power generation mode has a very important feature: it is produced as much as possible. The power generation power of the power plant is adjusted in real time according to the electric power of the power grid at the other end of the power grid. By the evening, everyone will turn on the lights. The power generation power of the generator will be adjusted in real time according to the parameters of the power grid. Essence

In the power station in Sichuan Province, the installed capacity of water conservancy power generation is 82 % of the total power generation capacity, and the runoff type water power plant (the water flows in the river, and the reservoir without water) takes up. Sixty percent of hydropower installation machines. The power generation power of the water conservancy power plant is subject to the amount of rivers' water volume.

The water flow during the Fengshui period is large. If all the water flowing through the water and power stations is used for power generation, the power consumption will not be completed. In the dry period, the water flow is too small, and all flowing water can not meet the power needs of power, resulting in lack of energy.

When the runoff water station is actively running, it will inevitably encounter the above two situations, resulting in the power generation capacity sometimes was wasted, and sometimes it cannot meet the power consumption needs.

Picture source: Author

The transmission line, high efficiency but planning construction requires time. my country's power transmission technology can be said to be the strongest in Blue Star (National Power Grid: Low -key, Low -key). In the early days of the design of the power grid, it will take into account the power consumption needs of various places and the power generation power of the power station. It may maximize the power generation capacity of the power plant to reduce the waste of energy. However, if you encounter an extreme situation once a decades, the design of the power grid will not be able to fight.

PART.2

The backing of the power grid system -energy storage technology

What should I do if the power grid is unable to fight? At this time, energy storage facilities need to be emergency. What is the energy storage facility? For example, it is equivalent to a small vault that stores the electric energy that is usually extra in the energy storage facilities, and take it out when necessary. This is the solution with the highest energy utilization rate. There are many types of energy storage systems, each with its own characteristics, mainly including pump storage, flywheel energy storage, compressed air storage, electrochemical energy storage, and super capacitor energy storage.

At present, the energy grid energy storage facilities with the most installed capacity in the world are pumping power stations. When the power use of electricity is used, the excess power of the pumping storage power station uses the net to store the water from the low -point reservoir to the reservoir to store it; By the peak period of electricity, then use the water in the reservoir to generate electricity. In this way, the extra power can be stored in the pump storage power station. When the power plant cannot meet the power demand, the pumping storage power station will be generated to share the pressure of the power station.

Anhui Xiangshui storage power station (picture source: Xinhua News Agency)

The power of the wind power and solar power generation fluctuates greatly and is very fast. The wind stopped for a while, or the cloud covered the sun for a while, and the power generation power of the two rolled like a roller coaster. This is also an important reason for the low energy utilization rate of wind power and photovoltaic power generation, which fluctuates too fast and causes the grid to unbearable. (Power Grid: My small heart can't stand this wave). The method to effectively improve these power utilization rates is also the construction of energy storage facilities. When the power generation power is reduced, the power energy is stored, and then the power generation power is used to help discharge, and the power generation power is "ironed" so that the power grid can bear it.

(Source: Author self -made)

Can the pump power station be competent? No, for optoelectronics and wind power, the reaction speed of pumping power stations is always "slowly shot", and there is no way to meet the requirements. The energy storage power station's reserve energy usually takes a few days, and the requirements for the construction of water storage power stations are relatively high. Therefore, the current pumping power stations are almost used to share the power generation pressure when the power system is at a large load.

Chemical batteries are currently most promising to meet the above requirements. The charging and switching of chemical batteries is quickly switched and responds very quickly. The most common energy storage equipment in life is chemical battery. The energy storage equipment of mobile phones, tablets, and electric vehicles is chemical batteries. However, although the performance of the battery is good, large -scale use will still face cost issues. Take the mobile phone charging treasure used as an example as an example. Without considering the ideal circumstances, 7.5 charging treasures with a capacity of 10,000 millions of capacity can be used to save time. This still uses a lithium ion battery with high energy density (of course, the price is also very touching). PART.3

The development of battery technology -no Moore's law at all

The Law of Moore is the experience of Gordon Moore, one of Intel founders, and its core content is: the number of transistors that can be accommodated on the integrated circuit will double every 18 months to 24 months. In other words, the performance of the processor doubles every two years, and the price drops to half the previous.

In the battery industry, this sentence can be said: about the battery energy density of about two years, or the price is reduced by half under the same energy density. Of course, this is simply a night in the battery industry. For more than 20 years of the development of the lithium -ion battery industry, it has been concentrated in communications, consumer electronics, and electric vehicle industries. In the larger application energy storage battery industry, due to the high cost of lithium batteries, it is difficult to cope with puncture, collision, and high and low temperatures. In other special environments, the application of large -scale energy storage batteries has always stayed in the experimental stage. The development of battery technology has a long way to go.

(Image source: References 2)

At present, the main research direction of domestic and foreign energy storage technology is electrochemical energy storage, and some new technologies have made gratifying progress during the laboratory stage. However, new technologies have a long way to go from the laboratory to a practical stage. When energy storage technology and power transmission technology develop to a brand new level, we are expected to get rid of the heavy dependence on fossil energy. Each major progress in the energy industry has brought humans to a new stage of development. What will happen in the future and how will technology progress bring to the lives of these ordinary people? let us wait and see.

references:

[1] HOSEIN, STEFAN HOSEIN, PATRICK KATTICK, WALTER RATAN, VARMA. (2016). Web Application for Power Grid Fault Management. 1-5. 10.1109/icias.2016.7824052.

[2] Wu Haowen, Wang Jun, Gong Yingli, et al. The development status and application prospects of energy storage technology [J]. Journal of Electricity, 2021, 36 (5): 10.

[3] Zhu Xueyan. Sichuan Provincial Hydropower Station abandoned the cause and response analysis [J]. Industrial innovation research, 2019 (9): 2. 2.

[4] Lai, Sing C, McCulloch, Et Al. Levelized Cost of Electricity for Solar Photovoltaic and Electrical Energy Storage [J]. Applied Energy, 2017.

[5] https://world-nuclear.org/information-library/current-nd-future- Gelectricity-nd-rgy-storage

[6] Wu Haowen, Wang Jun, Gong Yingli, et al. The development status and application prospects of energy storage technology [J]. Journal of Electricity, 2021, 36 (5): 10.

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