On June 30, the ±800 kV ultra-high voltage direct current (UHVDC) transmission project linking Shaanbei (Northern Shaanxi) and Anhui (hereinafter referred to as the Shaanbei-Anhui Project) under State Grid Corporation of China (SGCC) was fully completed and put into operation.

The project originates at the Baotashan Converter Station in Baota District, Yan’an City, Shaanxi Province, traverses three provinces of Shaanxi, Henan and Anhui, and terminates at the Hezhou Converter Station in Hefei City, Anhui Province. The total length of its DC transmission line stands at 1,055 kilometers. With a rated voltage of ±800 kilovolts, a rated transmission capacity of 8 gigawatts and a total investment of RMB 20.5 billion, the project marks the first commissioned UHVDC project during China’s 15th Five-Year Plan period. It also serves as another landmark project of SGCC to advance the national West-to-East Power Transmission Strategy, bearing profound strategic significance for enhancing national energy security, facilitating cross-regional optimal allocation of clean energy, and advancing the green and low-carbon transition of the energy sector.

Listed as a key project under the 14th Five-Year Plan for Power Development, the Shaanbei-Anhui Project will lift Shaanxi’s total external power transmission capacity to over 31 gigawatts upon commissioning, forming an external transmission layout featuring two AC and four DC corridors. The cross-regional power transmission capacity of the Northwest Power Grid will reach 103 gigawatts, delivering robust power support for economic and social development.

As a province where multiple national strategies converge, including the Integrated Development of the Yangtze River Delta, High-Quality Development of the Yangtze River Economic Belt, and High-Quality Development of the Central Region, Anhui has witnessed rapid growth of strategic emerging industries and sustained rise in total electricity consumption in recent years, generating an urgent demand for imported green power from outside the province.

Immediately after commissioning, the project will play a core role in safeguarding power supply, injecting ample electricity to Anhui amid the critical summer peak power demand period. It will also help Anhui build a grid framework supported by two back-to-back UHVDC cross-regional transmission channels for direct power supply and the East China UHV AC Ring Grid for inter-provincial power mutual support, greatly boosting the safety resilience of regional power grids and the efficiency of resource allocation.

The sending end of the project aggregates photovoltaic, wind power and high-efficiency coal-fired power from Shaanxi via a 750 kV AC system, while the receiving end connects to Anhui’s major load centers through a 500 kV AC system. Once fully operational, the project can transmit more than 36 billion kilowatt-hours (kWh) of electricity to Anhui annually, over half of which comes from renewable energy, enabling clean power generated in Shaanbei to light up Anhui thousands of miles away.

Reporters learned that supporting new energy installations with a total capacity of 11 gigawatts have been built at the sending end, making this Anhui’s first UHVDC channel capable of fully absorbing high-proportion renewable energy. Each year, the project will cut coal consumption by 5.5 million tons and reduce carbon dioxide emissions by 14.2 million tons, delivering remarkable energy conservation and emission reduction benefits.

During construction, SGCC rigorously implemented the management requirements of Six Refinements and Four Modernizations, and fully deployed standardized outcomes of the dual-800 UHV projects throughout the whole lifecycle and all dimensions of the project. A smart construction site management system was innovatively adopted for converter station construction to realize full digital control over the entire construction process. The project fully deployed domestically developed and controllable DC control and protection systems, fully localizing the "brain" of the transmission project and reinforcing the security shield for large power grids. The Baotashan Converter Station overcame technical hurdles of constructing converter stations on Grade IV collapsible loess, achieving zero safety incidents and zero quality defects, with excellent indicators recorded during live-line commissioning tests.

As major energy infrastructure, power grid projects feature long industrial chains and strong driving effects on related sectors. The Shaanbei-Anhui Project has directly driven coordinated development of upstream and downstream industrial chains, creating more than 15,000 jobs and yielding massive comprehensive economic and social benefits.

During the construction phase, the project boosted growth of sectors including electrical equipment manufacturing, raw material supply and engineering construction, fueled the transformation and upgrading of the equipment manufacturing industry, and strengthened the resilience and security of industrial and supply chains.

After commissioning, the project will help Shaanxi convert its energy advantages into economic strengths, accelerate the development of new industrialization in Anhui, foster new quality productive forces, and inject strong impetus into high-quality economic and social development of both Shaanxi and Anhui provinces.

This year marks the kickoff of the 15th Five-Year Plan period. SGCC is accelerating the development of a new-type power system, with fixed asset investment hitting a historic high and far exceeding the average annual level recorded in the 14th Five-Year Plan period. The company has launched a new round of large-scale UHV construction, with project commencement, approval and preliminary work advancing simultaneously at full swing.

To date, SGCC has completed and put into operation a total of 43 UHV projects, comprising 22 AC and 21 DC lines, with cross-regional and inter-provincial power transmission capacity exceeding 380 gigawatts. A backbone UHV AC grid framework has taken shape covering East China, North China, Central China and Southwest China. Deep integration of next-generation power dispatching control systems and power market trading platforms provides physical transmission channels and operational guarantees for medium-to-long term and spot power trading across provincial and regional borders.

During the 15th Five-Year Plan period, SGCC will accelerate the construction of a new-type power grid to further expand China’s cross-regional and inter-provincial power transmission capacity, consolidate the West-to-East Power Transmission and North-to-South Power Supply energy transport corridors, and deliver reliable and robust power support for high-quality economic and social development as well as people’s better lives.

(Written by Zhou Tirantan)