Smart grid to provide strong power support

The 11th meeting of the Financial and Economic Commission of the CPC Central Committee proposed the development of distributed smart grids. How to understand the distributed smart grid? What does it do?

The person in charge of the relevant departments of the National Energy Administration introduced that the distributed smart grid is based on the grid platform, and actively ADAPTS to the development of large-scale distributed new energy by improving the intelligence level of the grid.

On the one hand, on the power side, it can support distributed power supply access to the grid, meet electricity demand nearby, and provide users with continuous reliable power supply.

Du Zhongming, president of the General Institute of Electric Power Planning and Design, introduced that the development and utilization of new energy in China presents a centralized and distributed situation. The "large clean energy base + large power grid" approach mainly solves the problem of "electricity coming from afar", but long-distance transmission faces constraints from investment costs, land, environment and other factors. To promote the large-scale and high-proportion development of new energy, it is also necessary to rely on distributed power supplies, give full play to the advantages of being close to the load and nearby consumption, and achieve "electricity from the side".

On the other hand, on the load side, it can support the access of many kinds of load subjects such as electric vehicle charging piles, new energy storage, and virtual power plants, and meet the diversified "plug and play" access needs.

"The new energy output has the characteristics of intermittency, volatility, randomness, and so on. As the proportion of new energy continues to increase, the difficulty of maintaining the balance of the power system continues to increase, and the problem of the lack of flexibility adjustment resources of the traditional power grid becomes prominent." Du Zhongming said that the fine regulation of user electricity through the distributed smart grid is equivalent to recreating a "power plant", which will become a key means to ensure the reliable, stable and low-cost supply of power in the new power system.

"It is currently the peak period of electricity prices, and it is recommended to charge at 12 o 'clock during the low period of electricity prices." At 10 am, Mr. Zhang, a teacher at the Institute for Advanced Study of the University of Science and Technology in Hangzhou, originally planned to charge an electric car, and after adopting the suggestions provided by the charging app, he saved about 70% of the electricity bill. Last year, State Grid Hangzhou Power Supply Company put into operation in the campus "optical storage and charging integration" intelligent collaborative project, including distributed photovoltaic, energy storage power station, 3 sets of fast charging pile, 20 sets of slow charging pile and a set of optical storage and charging intelligent control system.

According to the data provided by the National Energy Administration, in recent years, the structure of China's distribution network has been further optimized, the level of intelligence has been greatly improved, and the acceptance capacity of distributed power has been steadily improved, fully guaranteeing the flexible access of more than 100 million kilowatts of various distributed power sources.

The development of distributed smart grid also needs to make efforts in key technologies and business models

The surveyed experts believe that the development of distributed smart grid, to improve the "hardware" of key technologies, business model "software" and other aspects of joint efforts.

At the key technical level, Du Zhongming believes that it is urgent to study the coordinated control technology that ADAPTS to massive distributed power supplies and multiple load access, the intelligent power grid scheduling and operation technology, and the key technologies for the digitalization and intelligent promotion of distributed smart grids.

As of the end of June this year, the number of pure electric vehicles in the country reached 8,104,000, and the installed installed capacity of distributed photovoltaic power generation was 127 million kilowatts, equivalent to the installed capacity of more than five Three Gorges power stations. "The charging load of electric vehicles has a large randomness, the photovoltaic power generation during the day can meet most of the power demand, the photovoltaic power generation at night has no output, the superimposed charging load of electric vehicles, the evening peak power balance and the safe and stable operation of the system will face a great test." Du Zhongming suggested building a technical support system for the integration of power distribution and electricity consumption, and opening up the "last kilometer" of the distribution network to connect users.

At the business model level, it is necessary to improve the price mechanism and market rules of "wall sale of electricity" (that is, market-oriented trading of distributed generation). "' Selling electricity through the wall 'helps to promote the consumption of renewable energy nearby, but at present, the charging standard for' network fees' is not clear." How to balance the demands of transaction parties and grid enterprises, and improve the electricity price mechanism to support the self-use and nearby use of distributed clean energy generation needs to be further explored." Du Zhongming said.