With the continuous advancement of large-scale construction of wind and solar bases, it is increasingly important to improve the level of new energy power consumption and utilization. In order to effectively ensure the consumption of new energy, since the beginning of this year, a number of UHV power grid projects and pumped storage power station projects have started intensively, which is of great significance for ensuring the safe and reliable supply of electricity, helping the construction of new energy systems and the high-quality development of new energy.
UHV construction ushered in a peak
my country is rich in clean energy, but the distribution of resources and demand is reversed. The UHV power grid has the advantages of long distance, large capacity, and low loss. The transmission capacity can reach several times that of 500 kV ultra-high voltage transmission, and the transmission distance can reach thousands of kilometers. The rapid transfer of clean energy to the more economically developed central and eastern regions to solve the contradiction between power supply and demand is a key part of the new energy supply and consumption system.
Under the "double carbon" goal, the installed capacity of new energy power stations in the western and northern regions is rapidly increasing, while the construction speed of UHV projects lags behind that of large wind and solar bases. From the perspective of the construction period, the photovoltaic power station is 3 months to 6 months, the wind power is 1 year, and the UHV is 1.5 years to 2 years. According to the normal rhythm, the UHV power grid should be built first, so as to form a "source-network match" with the faster-built wind and solar power stations, so that they can be put into operation at the same time and well consumed. In the past few years, due to factors such as the epidemic situation and the delay in UHV approval, the progress of power grid construction has lagged behind to a certain extent. The transmission capacity of the completed UHV projects is far from meeting the needs of clean energy transmission, and it is urgent to speed up construction to improve the ability to connect new energy to the grid.
On February 16, the State Grid Jinshang-Hubei ±800 kV UHV DC transmission project started, which opened the prelude to the construction of major power grid projects this year. After the completion of the project, nearly 40 billion kWh of electricity can be transmitted to central China every year, which is equivalent to one-sixth of the annual electricity consumption of Hubei Province, and will play an important role in meeting the reliable supply of electricity.
On March 16, my country's first UHV project of "integration of wind and thermal storage" power transmission - State Grid Longdong to Shandong ± 800 kV UHV DC transmission project started construction. Xing Zhou, deputy general manager of State Grid Gansu Electric Power Company, said that the Longdong-Shandong UHV power transmission project provides an integrated transmission solution of "UHV + wind-solar thermal storage", with an annual transmission of 36 billion kWh. The project will promote the consumption of new energy in Gansu on a larger scale, and will also inject new momentum into the high-quality development of Gansu and Shandong provinces.
Xin Baoan, chairman of the State Grid Corporation of China, revealed that the State Grid plans to invest more than 520 billion yuan in 2023, a record high and an increase of about 4% year-on-year. During the "14th Five-Year Plan" period, the State Grid plans to invest 2.4 trillion yuan to vigorously promote the construction of a new energy supply and consumption system. UHV construction is expected to usher in a new peak of development.
At present, the State Grid Corporation has put into operation 33 of the world's most advanced UHV projects, and built a super-large power grid with the highest voltage level in the world, the largest installed capacity, and the strongest resource allocation capability, which has significantly improved the long-distance power transmission capacity of my country's power grid. It has promoted the vigorous development of "West-East Power Transmission, North-South Power Supply", and played an important role in ensuring safe and reliable power supply and promoting green and low-carbon development.
Large "charging treasure" ready to go
Although the UHV power grid solves the problem of large-scale transmission of new energy, due to the intermittent and fluctuating characteristics of new energy power generation, how to ensure the safe and stable operation of the power system and flexible economic dispatch is a major problem.
Pumped storage has multiple functions such as peak regulation, valley filling, frequency regulation, phase regulation, energy storage, emergency backup and black start. Carbon Clean can flexibly adjust the power supply, which can act as a stabilizer and regulator for the safe operation of large power grids, as well as a "power bank" that supports the development of new energy. At present, my country is in a critical period of energy green and low-carbon transformation and development. The large-scale and high-proportion development of new energy sources such as wind power and photovoltaic power generation makes the demand for power regulation more urgent. The construction of a new power system puts forward higher requirements for the development of pumped storage.
Since the beginning of the year, pumped storage has ushered in a new round of construction peak. On March 18, Liaoning Dayahe and Xingcheng pumped storage power station projects started. After the completion of the two pumped-storage power stations, the double regulation capacity will reach 5.6 million kilowatts, which is of great significance for alleviating the peak-shaving pressure of the Northeast Power Grid and improving Liaoning's power supply capacity.
Wu Jun, general manager of State Grid Xinyuan Group Co., Ltd., said that the two pumped storage power stations have a designed annual generating capacity of 2.809 billion kWh. The unit responds quickly and has strong load tracking ability, which can effectively stabilize the impact of randomness and fluctuation of new energy, and ensure that new energy power can be generated, stored and used well.
According to the person in charge of State Grid Liaoning Electric Power Co., Ltd., 55 major power grid projects have been started this time. Among them, a batch of new energy supporting power grid projects such as the Fuxin Toyota 500 kV substation will guarantee more than 3 million kilowatts of wind power after they are put into operation. The reliable grid connection of the project will help the local area build a new energy base of 10 million kilowatts. The construction of pumped-storage power stations and new energy supporting grid projects will strongly support the high proportion of clean energy development in Liaoning and accelerate the green transformation of energy and power.
In addition, Hubei Tongshan Pumped Storage Power Station and Gansu Yumen Pumped Storage Power Station have both started construction recently. During the "14th Five-Year Plan" period, the pumped storage power station in the State Grid's operating area will usher in the construction peak. It is estimated that the newly put into operation installed capacity will exceed 27 million kilowatts, and the total scale of commissioning will reach 50 million kilowatts by 2025.
In order to promote the rapid development of pumped storage and meet the needs of new power system construction and large-scale and high-proportion new energy development, the National Energy Administration issued the "Pumped Storage Medium and Long-term Development Plan (2021-2035)" and proposed that in accordance with energy nuclear exhaustion, Based on the principle of being fully open, the construction of pumped storage power stations is approved in the library of key implementation projects in the planning. By 2025, the total scale of pumped storage put into operation will double that of the 13th Five-Year Plan, reaching more than 62 million kilowatts; by 2030, the total scale of pumped storage put into operation will double that of the 14th Five-Year Plan, reaching 120 million About kilowatts.
Improve the reasonable market trading mechanism
The electricity market is an important part of the new power system. With the large-scale access of new energy, the power system will accelerate its development towards cleanliness and low-carbonization, and the role of power generation resources and system characteristics will change, profoundly changing the basic form and operating characteristics of the power system, and also putting forward new challenges for the construction of the power market. Higher requirements.
Li Xiangliang, deputy general manager of China Huaneng Group, believes that the rapid growth of various economic entities involved in the new power system, the more frequent and diverse interactions across time and space, and the overlapping of security, environmental and economic goals are mutually restrictive. Geographical restrictions to achieve global optimization.
At 13:34 on March 5, Gansu's photovoltaic output reached 10.05 million kilowatts, breaking through 10 million kilowatts for the first time. At present, Gansu has established Jiuquan 10 million-kilowatt wind power base, Tongwei 10 million-kilowatt wind power base, Zhangye, Jinchang, Wuwei, and Jiuquan 4 million-kilowatt photovoltaic power generation bases. As of the end of 2022, Gansu's new energy installed capacity will be 35.19 million kilowatts, ranking eighth in the country, with installed capacity accounting for 51.9%, ranking third in the country.
In order to effectively promote the consumption of new energy power generation, the State Grid Gansu Electric Power Company has improved the power market trading mechanism and incorporated energy storage power stations into the provincial power spot market and auxiliary service market. Innovatively launched the "D+3" daily rolling transaction of contract power transfer on the power generation side to achieve uninterrupted continuous operation on a daily basis.
Many places are actively promoting the construction of new energy market-oriented consumption mechanisms. At the first high-end electric power market forum recently hosted by the China Electricity Council, Xie Kai, executive director of the electric power market branch of the China Electricity Council, introduced that in terms of new energy participating in the medium and long-term market, new energy in Shanxi Province will give priority to guarantee when participating in market-oriented transactions It is clear that the transaction method is mainly based on bilateral negotiations; Sichuan Province has approved the annual guaranteed utilization hours of new energy, and the electricity exceeding the hours will participate in medium and long-term transactions, competing with hydropower on the same stage. New energy stations independently participating in mid-to-long-term transactions in Shandong Province and thermal power units in the province participate in the mid-to-long-term market and spot market on an equal footing.
Among the provinces with spot long-term trial operation, new energy in Gansu and other provinces participates in the spot market in the form of "quotation and quantity", competing with thermal power on the same platform, allowing new energy to correct ultra-short-term forecasts and power generation capacity in the real-time market; Shanxi new energy units follow Participate in the spot market by means of "reporting quantity but not quoting".
Chen Guoping, deputy general manager of the State Grid Corporation of China, said that under the "dual carbon" goal, with the further increase of new energy installed capacity, the system will face the risk of insufficient peak-shaving capacity, and a reasonable market mechanism needs to be established: on the power generation side, incentives for flexible transformation of thermal power, Construction of pumped storage power stations; on the demand side, stimulate and release micro-grids, energy storage, virtual power plants and other regulation resources, guide the two-way interaction between power generation and utilization, and promote the consumption of new energy.