"Ten direct and two cross" west-to-east power transmission delivers green energy

China Energy Storage Network News: On November 24, 2020, with the commissioning of Unit 9 of the Wudongde Right Bank Power Plant on the Jinsha River, Yunnan Province's installed power capacity exceeded 100 million kilowatts, reaching 100.73 million kilowatts, equivalent to the installed capacity of 4.5 Three Gorges power stations, ranking sixth in the country. The installed capacity of clean energy, mainly hydropower, accounted for 85%, and the estimated power generation in 2020 accounted for more than 88%, reaching the international first-class level.

Since the 13th Five-Year Plan, China Southern Power Grid Co., Ltd. (hereinafter referred to as China Southern Power Grid) has continued to promote the national "West-to-East Power Transmission" strategy. As of the end of September last year, the amount of electricity transmitted from Yunnan to the West exceeded 600 billion kWh, which is 1.4 times the total amount of electricity transmitted before the 13th Five-Year Plan (1993-2015). Among them, the amount of electricity transmitted from Yunnan accounts for 63% of the total amount of electricity transmitted from the West to the East, all of which is clean energy, which is equivalent to reducing the burning of 170 million tons of standard coal for Guangdong, Guangxi and Hainan, reducing carbon dioxide emissions by 460 million tons and sulfur dioxide emissions by 3.3 million tons, making positive contributions to the optimization of resource allocation and mutual benefit and win-win situation between the east and the west.

"Three horizontal, two vertical and one center" strong power grid

Yunnan's power has grown from small to large, from weak to strong, from small rivers to large rivers, from small units, small power plants, and small power grids to large units, large power plants, large power grids, and ultra-high voltage. It has created the "Lubuge shock wave" and "Manwan model" and other far-reaching experiences in the history of China's power reform and development, opened up three power markets within the province, outside the province, and abroad, and Yunnan's power has achieved a historic leap and take-off. Especially since the 18th National Congress of the Communist Party of China, Yunnan Power Grid has once again opened a new leap. Today, the energy industry based on electricity has become the first pillar industry in Yunnan Province. Yunnan Power Grid has become an important power hub for the national "West-to-East Power Transmission" strategy and the "Belt and Road" facing South Asia and Southeast Asia. It is the world's most technologically advanced, most complex, and greenest AC/DC parallel asynchronous provincial power grid.

Over the past 70 years, Yunnan's power development has been strong. The province's installed capacity has increased from 14,520 kilowatts in the early days of the founding of the People's Republic of China (accounting for 0.78% of the country's installed capacity and ranking 16th in the country) to 100,000, 1 million, 10 million, 50 million, and 80 million kilowatts; the voltage levels have successively crossed 110 kV, 220 kV, 500 kV, and 800 kV, continuously ensuring the safe and stable operation of the large power grid, and significantly increasing its ability to serve Yunnan's economic and social development. China Southern Power Grid has invested nearly 200 billion yuan in the construction of Yunnan Power Grid, focusing on the construction of large-scale hydropower station transmission and backbone power grids, strengthening and improving urban distribution networks and rural power grid upgrades, and fully supporting the grid-connected power generation of units. Based on Yunnan's location advantages and resource endowments, Yunnan Power Grid has thoroughly implemented the national strategy of sending electricity from west to east, relying on the large platform of China Southern Power Grid to optimize resource allocation, continuously expand the scale of sending electricity from west to east, and promote the transformation of Yunnan's resource advantages into economic advantages. At present, Yunnan Province has built a 500 kV main grid with "three horizontal, two vertical and one center". The 220 kV backbone power grid covers 16 prefectures (cities) in the province, and 110 kV supplies electricity to townships and key enterprises, forming a complete main grid. The province transmits large-capacity electricity to Guangdong, Guangxi and Hainan over long distances through the "ten direct and two cross" channels, with a transmission capacity of 39.15 million kilowatts, ranking first in the country in inter-provincial power transmission capacity.

At the same time, Yunnan Power Grid Company has radiated to neighboring Southeast Asian countries such as Vietnam, Myanmar, and Laos through 10 cross-border power trade channels above 110 kV. By giving full play to the role of the large power grid resource allocation optimization platform, it vigorously supports the access of clean energy power generation to the grid. On the other hand, it has taken a variety of measures such as optimizing the operation mode of the power grid, implementing cross-basin hydropower optimization scheduling, and giving play to the market trading mechanism to promote the consumption of clean energy in a wider range. Since 2019, the utilization rate of hydropower has reached more than 98%.

"Ten UHV DC + two 220 kV AC" West-to-East Power Transmission

Yunnan is the province in China that started the earliest and developed the fastest in west-to-east power transmission. In 2020, with the gradual commissioning of the Lugaozhao DC project and the Kunliulong DC project, the west-to-east power transmission channel of the Yunnan power grid has developed into a power transmission pattern of "ten ultra-high voltage DC circuits + two 220 kV AC circuits".

Yunnan Province has a hydropower resource reserve of 104 million kilowatts, with an exploitable installed capacity of 97.95 million kilowatts, ranking second in the country; it has rich coal resources, with a prospective coal reserve of more than 69 billion tons and a proven reserve of 24 billion tons, ranking ninth in the country; solar energy, wind energy, geothermal energy and other resources are also very rich, with broad prospects for development and utilization. After more than 20 years of development, Yunnan has become an important clean energy base in the southern region. So far, the installed capacity of Yunnan Province has exceeded 100 million kilowatts, ranking sixth in the country, and the installed capacity of clean energy, mainly hydropower, accounts for more than 85%, reaching the national leading level.

The State Grid Corporation of China has actively played the role of a regional resource optimization and allocation platform and vigorously promoted the construction of the west-to-east power transmission channel. Since the 13th Five-Year Plan, six DC channels, namely Jinzhong, Yongfu, Luxi, Xindong, Lugaozhao and Kunliulong, have been built and put into operation. Currently, a total of 12 large channels, including "ten DC and two AC", have been built in Yunnan to transmit electricity to Guangdong, Guangxi and Hainan. By the end of next year, the maximum transmission capacity will reach 42.15 million kilowatts, which is 169 times the initial transmission capacity and about twice the end of the 12th Five-Year Plan. The inter-provincial power transmission capacity ranks first in the country.

With the continuous enhancement of power transmission capacity, from 2016 to 2019, the amount of electricity transmitted from west to east in Yunnan was 110.1, 124.2, 138.1, and 145.2 billion kWh respectively, achieving a "four consecutive jumps", which strongly supported Yunnan's electricity-based energy industry to leap into the province's largest pillar industry, realized the transformation of clean hydropower resource advantages into economic advantages, and promoted the coordinated development of the east and west.

Green Energy "Pioneering"

On November 19, 2020, the Guangzhou Power Exchange held a signing ceremony for the 2021 Southern Region Cross-Regional and Cross-Provincial Power Purchase and Sales Contract in Kunming, Yunnan. 11 market entities from power grid companies and power generation companies signed 11 cross-provincial power purchase and sales intention contracts for 2021, with a contracted electricity volume of 195.8 billion kWh, which exceeds 90% of the average annual power transmission scale of the West-to-East Power Transmission in the past three years. It has locked in the 2021 West-to-East Power Transmission arrangement in advance, laying a solid foundation for the signing of the "14th Five-Year Plan" framework agreement.

Since 2020, Yunnan Power Grid Company has actively overcome the adverse effects of the epidemic, continued to promote the transmission of electricity from west to east, and maximized the consumption of Yunnan's clean energy, achieving the basic full consumption of wind power and photovoltaic power. From January to October, the amount of electricity transmitted from west to east reached 128.65 billion kWh, an increase of 25.37 billion kWh over the annual monthly plan. Among them, Yunnan's monthly power transmission in July and August set a new record, reaching 21.605 billion and 23.73 billion kWh respectively, an increase of 20.3% and 31.2% year-on-year respectively; the power transmission in September reached 21.75 billion kWh, a year-on-year increase of 37.55%, and remained above 20 billion kWh for three consecutive months.

In order to ensure the implementation of the national strategy of sending electricity from west to east, Yunnan Power Grid Company, on the one hand, has made every effort to promote channel construction and give full play to the large platform advantages of China Southern Power Grid Company. In the flood season of 2020, the Lugaozhao DC project and the Kunliulong DC project were successfully completed and put into operation to the Guangdong end, which improved the capacity of Yunnan's west-to-east power transmission channel during the main flood season, promoted the establishment of water-fire mutual assistance between Yunnan and Guizhou, and solidly carried out the optimal allocation of resources and mutual assistance between provinces and grids within the scope of the Southern Power Grid, making full use of the capacity of Yunnan's west-to-east power transmission channel, and promoting the consumption of clean energy in Yunnan. On the other hand, Yunnan Power Grid Company actively promoted the signing of the West-to-East Power Transmission Agreement. Actively coordinate the Yunnan Provincial Government, the Guangdong Provincial Government, the Guangxi Autonomous Region Government, and the Southern Power Grid Company to jointly sign the 14th Five-Year Plan and the Medium- and Long-Term West-to-East Power Transmission Framework Agreement to further consolidate the results of West-to-East Power Transmission. In addition, Yunnan Power Grid Company uses the capacity of channels outside the agreement to promote the full consumption of clean energy in Yunnan. Make full use of the capacity of the direct current channel from Yunnan to Guangdong and the power transmission potential of the AC section between Guangdong and Guangxi to increase the transmission of surplus hydropower in Yunnan. In 2019, Yunnan achieved a coordinated hydropower utilization rate of 99.33%, wind power and photovoltaic power were basically fully absorbed, and non-fossil energy power generation accounted for 90.98%. It is estimated that by 2030, the total installed capacity of clean energy in Yunnan Province will reach 130 million kilowatts, and the maximum power transmission capacity will exceed 50 million kilowatts, becoming one of the most important green energy bases and west-to-east power transmission energy bases in the country. The power industry will become the main force and vanguard of Yunnan Province in building a green energy brand.