Northern Shaanxi-Anhui ±800 kV UHVDC transmission project put into operation

The Northern Shaanxi-Anhui ±800 kilovolt ultrahigh-voltage direct current (UHVDC) transmission project of State Grid Shaanxi was completed and put into operation on June 30. The project is China's first UHVDC project to enter operation during the 15th Five-Year Plan (2026-30) and another landmark project in its service of the national west-to-east power transmission strategy.

State Grid said the project is of major strategic significance for enhancing national energy security, promoting cross-regional optimal allocation of clean energy and advancing green and low-carbon energy transition.

Energy security and safety bear on the national economy and people's livelihoods. China's 15th Five-Year Plan calls for accelerating construction of a clean, low-carbon, safe and efficient new energy system; building an energy powerhouse; and emphasizes striving to build a new-type power system that optimizes the national power flow and cross-regional corridor layout.

State Grid, as a State-owned enterprise carrying out national strategic missions and safeguarding national energy security, coordinates development, security, supply guarantees and transition. It continues to optimize grid development layout, accelerates UHV and supporting grid construction, shoulders power supply responsibility through practical action, and remains a main force in building a new-type power system, supporting the construction of a new energy system and contributing to Chinese modernization.

The Northern Shaanxi-Anhui project starts at the Baotashan converter station in Yan'an city, Shaanxi province, passes through Henan province and ends at the Hezhou converter station in Hefei, Anhui province.

The DC line is 1,055 kilometers long. The project has a rated voltage of ±800 kV, a rated capacity of 8 gigawatts and a total investment of 20.5 billion yuan ($2.8 billion). The sending end uses a 750 kV AC system to gather Shaanxi's solar, wind and energy-saving thermal power, while the receiving end connects to the Anhui load center via a 500 kV AC system.

Once fully operational, the link is to transmit more than 36 terawatt-hours of electricity a year to Anhui, with new energy accounting for more than 50 percent. This is to support reliable power use in Anhui and East China and play an important role in ensuring medium- and long-term power supply-demand balance and upgrading the energy structure.

State Grid called the project a key, green livelihood project supporting high-quality development in Shaanxi and Anhui, with urgent construction needs and major tasks. It said all participating units implemented its deployment requirements, overcame multiple challenges, crossed the Qinling Mountains and the Huaihe River and completed construction, adding another artery to the west-to-east power transmission strategy.

The project is a key element in China's 14th Five-Year Plan (2021-25) for power development. After commissioning, Shaanxi's outbound power capacity will exceed 31 GW, forming a "two AC, four DC" outward transmission pattern, while the Northwest China grid's cross-regional outbound capacity will reach 103 GW.

Anhui — where the Yangtze River Delta integration, Yangtze River Economic Belt and central region high-quality development strategies overlap — has seen strategic emerging industries and electricity consumption grow, creating urgent demand for imported green power. The project will provide support immediately upon operation, inject power into Anhui during the summer peak. It will also help the province form a grid pattern with double-circuit UHVDC cross-regional corridors as direct supply guarantees and the East China UHV AC ring network as inter-provincial mutual support, improving regional grid security and resource allocation.

The sending end has 11 GW of supporting new energy capacity and the link is Anhui's first UHVDC channel designed to absorb a high proportion of renewable energy. The project can replace 5.5 million metric tons of coal consumption and cut 14.2 million tons of carbon dioxide emissions a year, with significant energy-saving and emission-reduction benefits.

The company said it will promote large-scale clean energy development in Northern Shaanxi, optimize Anhui's energy supply structure, raise the share of green electricity consumption and advance the comprehensive green transition.

During construction, State Grid said converter stations used a smart construction site management system for digital control of the entire process. The project applied an independent, controllable DC control and protection system, localizing the project's brain and strengthening grid safety.

The Baotashan converter station overcame the difficulty of building in Class IV collapsible loess (a type of sediment) and achieved zero accidents and quality defects, with excellent energization commissioning indicators.

Grid projects have long industry chains and strong driving effects. The Northern Shaanxi-Anhui link directly drives upstream and downstream industry chains, provides more than 15,000 jobs and generates huge comprehensive economic and social benefits, according to the company.

During construction, it boosted electrical equipment production, raw material supply and engineering construction, promoted equipment manufacturing upgrading, and improved industry and supply chain resilience and security. After operation, it will help convert Shaanxi's energy advantages into economic advantages, support Anhui's new industrialization, foster new quality productive forces and inject momentum into high-quality economic and social development in both provinces.

This is the first year of the 15th Five-Year Plan. State Grid said it is accelerating new-type power system construction, with fixed-asset investment achieving a historic breakthrough and rising sharply from the 14th Five-Year Plan's annual average. In UHV construction, it has launched a new round with a peak in simultaneous construction, approval and preliminary work, the company said.

State Grid has cumulatively built and commissioned 43 UHV projects with cross-regional and interprovincial transmission capacity exceeding 380 GW. It has formed UHV AC backbone grids in East, North, Central and Southwest China and integrated a new-generation dispatch control system with a power market trading platform to provide physical channels and operational support for interprovincial medium- and long-term and spot transactions.

During the 15th Five-Year Plan, State Grid said it will accelerate new-type grid construction, raise China's cross-regional and interprovincial transmission capacity and consolidate the west-to-east and north-to-south energy transmission corridors.