Building a global energy internet to solve the dilemma of new energy development

China Energy Storage Network : The main problems and challenges facing the development of new energy in Gansu are, first of all, the prominent contradictions in grid connection and consumption. During the 12th Five-Year Plan period, the average annual growth rate of installed power capacity in Gansu Province was 18.15% (of which the average annual growth rate of new energy was 62.87%), which was 2.34 times the average annual growth rate of electricity consumption in the whole society. While new energy is growing rapidly, the growth rate of electricity consumption in the province has slowed down, and the contradiction between power supply and demand has become increasingly prominent. Surplus electricity is difficult to be consumed in Gansu and even in the Northwest Power Grid. The built Northwest to Central China UHV transmission channel has no landing point in Gansu and the power distribution ratio is low. The approval of the UHV transmission projects under construction is relatively lagging, and the transmission capacity of the power grid has not been significantly improved. In addition, there is a lack of policies on the consumption of new energy, and the problem of new energy consumption is becoming increasingly serious, and the abandonment of wind and solar power is constantly increasing.

Secondly, the peak-shaving and frequency-regulating capacity is insufficient. Under the policy incentives of the Chinese government to encourage the development of new energy and the vigorous promotion of local governments, the installed capacity of new energy in Gansu has grown too fast, and the development scale far exceeds the local carrying capacity, and the peak-shaving and frequency-regulating capacity of the power grid is seriously insufficient. At present, the grid-connected capacity of new energy alone is as high as 1.37 times the maximum load of the province's unified regulation, and the system peak-shaving capacity gap is about 4.5 million kilowatts, making it very difficult for the Gansu power grid to regulate peak power.

Finally, the power grid has a high safety risk. There are many new energy stations in Jiuquan, and new energy accounts for 72% of the local installed capacity. The power generation output is intermittent and volatile, and the operation and control are difficult. The Hexi area is located at the end of the power grid, and there is a lack of strong power supply support locally, so reactive voltage control is very difficult. As the proportion of new energy continues to rise, the risk of safe operation of the power grid continues to increase.

In response to the rapid development of new energy, Gansu Power has successively built two Gansu Provincial Engineering Technology Centers, one Gansu Provincial Key Laboratory, one State Grid Corporation Key Laboratory, and one State Grid Corporation Science and Technology Research Team, and carried out a series of major research projects including two national "863" projects and one national science and technology support project. Major breakthroughs have been made in the research and development of key technologies in the fields of new energy power generation equipment detection and operation monitoring, power prediction, cluster control, dispatching operation, transmission and consumption, etc., effectively improving the stability of Hexi Power Grid operation and its ability to accept new energy; overcoming technical difficulties such as intermittent power cluster coordination control and wind farm power accurate prediction, greatly improving the adjustability and controllability of wind farms, and increasing the new energy power generation capacity by about 6%; through the replacement of self-provided power plants with new energy and point-to-point local consumption, the new energy power generation capacity has been increased by 11.4%. However, due to the impact of the continued economic downturn, the contradiction between supply and demand has become increasingly prominent. In 2015, the province's wind abandonment rate reached 39% and the solar abandonment rate reached 31%, which seriously restricted the further development of new energy.

The Global Energy Internet is a strong smart grid with UHV power grid as the backbone, clean energy transmission as the main focus, and global interconnection. The Global Energy Internet provides methods and ideas for the sustainable development of new energy. Through the development of smart grid technology, the operation and control problems caused by the large-scale development of wind power and photovoltaic power and high-proportion access to the power grid can be solved; through the development of UHV power grid, the long-distance, large-scale and efficient configuration of clean energy can be realized.

甘肃具有全球能源互联网落地实践的基础条件。在地缘优势方面，甘肃地处新丝绸之路经济带咽喉、国家能源输送走廊、新能源基地群枢纽位置，是国内外大规模高比例新能源发展的典型地区，目前已建成750千伏主网架，开工或规划建设“两直一交”3条特高压电网工程，交直流混联运行的特高压骨干网架将要形成。同时，大电网接入大规模新能源运行控制水平显著提升。新能源资源丰富，风电装机国内第三、世界第七，光伏装机国内第一、世界第七。

Currently, Gansu is focusing on building the Western China Demonstration Base of the Global Energy Internet, jointly carrying out research on major issues of the Global Energy Internet, key technology research and development, and demonstration project construction, exploring paths, accumulating experience, and providing demonstrations for the development of China's energy Internet.

The consumption of new energy is a systematic problem. It is necessary to combine economic and technical means and take multiple measures to achieve the healthy development of new energy. The first is to open up the market within the province. The power generation side promotes the use of new energy to replace self-provided power plants in multiple modes. The power sales side carries out multiple channels to replace electricity such as new energy heating. Various measures are taken to promote the priority consumption of new energy in the province. The second is to expand the market outside the province, increase the power transmission across provinces and regions, effectively increase the proportion of new energy transmission, and promote the consumption of surplus new energy across the country. Finally, it is to study the establishment of market mechanisms, including renewable energy quotas, power green certificate trading, carbon emission reduction trading, etc.

Gansu Power also actively conducts research on key technologies for new energy consumption. It focuses on research and demonstration applications of key technologies for ultra-large-scale transmission of new energy in UHV power grids, accelerates the construction of physical channels for power transmission in Gansu power grid, and strives to complete the ±800 kV Jiuquan-Hunan UHV DC project in 2017 and the ±800 kV Longdong-Jiangsu UHV DC project in 2019, increasing the transmission capacity by 18 million kilowatts. Promote the construction of the 1,000 kV Qinghai Tala-Gansu Tianshui-Longnan-Sichuan Guangyuan-Chongqing Changshou UHV AC project, build a western synchronous power grid that connects the northwest with the Sichuan, Chongqing and Tibet regions, and realize large-scale optimization of wind, solar, hydro and thermal power and bundled transmission; implement demonstration projects for coordinated control of power grids, power sources and loads to improve the capacity for new energy consumption and transmission; carry out research and demonstration of key technologies for large-scale utilization of a high proportion of renewable energy in the Hexi Corridor, explore the feasibility and technical routes of joint transmission of a higher proportion of renewable energy bases, and build an intermediate experimental research and demonstration platform for key technologies of the global energy Internet; carry out research and demonstration of optimization of the phase-shifting operation characteristics of new energy and solve the problem of insufficient reactive voltage control means in regional and terminal power grids.

I believe that only by relying on the strategic concept of the global energy internet and building a global energy internet demonstration base in western China in Gansu can we fundamentally solve the dilemma of new energy development in Gansu. At the same time, I also hope that through Gansu’s own efforts, we can accumulate successful experience and create a Chinese model for promoting the construction of the global energy internet.