Gansu Green Power Travels Thousands of Miles to Yangtze Delta

15 GWh of green electricity from Gansu was recently transmitted to Zhejiang.

'This is Gansu's first cross-province and cross-region green power transaction,' said He Xiqing, Executive Director of Gansu Electric Power Trading Company. After the transaction was completed on the e-trading platform of Beijing Power Exchange Center, Gansu's green power went directly to Zhejiang through the Ningdong- Shaoxing ±800kV UHVDC transmission line.

Rich in wind and solar resources, the potential capacities of wind and solar power in Gansu are 560 GW and 9,500 GW respectively. Up to now, the installed capacity of new energy accounts for nearly half of the total, and the utilization rate of electricity from new energy has increased from 60.2% in 2016 to 96.83% today. In 2021, new energy generation in Gansu exceeded 40 TWh and the carbon dioxide emissions were reduced by about 40 million tons.

East-bound electricity transmission from Gansu will top 100 TWh annually

At the foot of the Qilian Mountains more than 60 kilometers north of urban Zhangye, Gansu province, wind turbines are rotating with the wind. This is the Pingshanhu Wind Farm. 'All the wind turbines are equipped with wind direction sensors and they will 'follow the wind' automatically', said Zhang Guangtai, head of the wind farm, 'the farm generates 1.50 MWh of electricity in one hour.'

On the Gobi Desert in Jinchang City, the blue photovoltaic panels are in orderly array. A tracking system is installed to enable the panels changing the angle towards the sun, and to ensure that the sun shines directly on the photovoltaic panels. It has increased the generation by 20% to 30%.

'The clean energy industry is under rapid and large scale development,' said Ye Jun, Chairman of State Grid Gansu Electric Power. 'By building out-bound UHV transmission lines, the surplus electricity is delivered to central and eastern China.'

In June 2017, Gansu completed and put into operation the Jiuquan-Hunan ±800kV UHVDC Transmission Project, the first power line aimed at transmitting new energy power in China. At the Qilian Converter Station, the transmitting end, green electricity from the Hexi Corridor is boosted to 800 kV and then transmitted directly to Hunan. As of now, the Qilian Converter Station has transmitted a total of 94.8 TWh of electricity to Central China, accounting for about 50% of the out-bound electricity from the Gansu power grid, said Li Ningrui, Executive Vice President of EHV Company of State Grid Gansu Electric Power and head of the Qilian converter station.

'In 2022, we will fully implement State Grid's action plan for China's climate goals and vigorously promote the construction of a new energy supply and consumption system based on UHV transmission lines,' said Ye Jun. With the joint efforts of government authorities and enterprises, the Gansu-Shandong UHVDC Transmission Project is in the early stage of approval now. In addition, Gansu has signed agreements on electric power cooperation with Zhejiang and Shanghai, and Gansu-Shanghai and Gansu-Zhejiang UHV transmission projects are also being promoted. 'It is expected that by the end of the 14th Five-Year Plan, the annual out-bound electricity from Gansu will exceed 100 TWh,' Ye Jun added.

Maximize clean energy consumption through coordinated dispatching

At Gansu Dispatching Center, all power generation data are shown in real time on the screen. 'With the new energy generation cluster control system, the total generation and output of each power plant can be controlled smartly,' said Yang Chunxiang, deputy director of the Dispatching Center of State Grid Gansu Electric Power.

The forecast of wind and solar power is indispensable to smart control. 'New energy power forecast is an important technical means to ensure the safe and stable operation of power systems and efficient consumption of new energy,' said Zheng Wei, Chief Expert of Reliability Management at State Grid Gansu Electric Power Research Institute. Based on the forecasted results, the dispatching center can balance the power demand and supply of the whole grid and optimize the operation plan of generating units to reserve space for and improve the consumption of new energy power generation.

In recent years, Gansu has built the world's largest combined wind and solar resources monitoring network composed of 44 real-time wind measuring towers, 18 automatic meteorological photometric stations, and 10 haze and dust monitors etc. 'The data on resources of all wind farms and photovoltaic power plants within the Hexi Corridor can be monitored in real time,' said Zheng Wei. In order to improve the accuracy of wind and solar power forecasting, State Grid carried out technical researches such as photovoltaic minute-level ultra-short-term forecasting. 'The yearly new energy power generation forecasted at the beginning of 2021 was 43.2 TWh while 43.8 TWh was actually completed, achieving an accuracy of nearly 99%.'

At the same time, power sources for peak regulation such as pumped storage, chemical energy storage, and thermal power for supporting new energy development are also under construction. 'The Yumen Changma Pumped Storage Power Plant is included in the national mid- and long-term plan for pumped storage, and the single largest electrochemical energy storage power plant in the world has been built and put into operation in Gansu,' said Yang Chunxiang. 'By combining energy storage and new energy power plants into virtual power plants for peak regulation, the peak regulation capacity of the power grid system can be further improved to enhance the stability and reliability of new energy.'

The industrial supporting system gets more out of wind and solar resources

In an industrial park for new energy equipment manufacturing in Wuwei, a set of independently developed wind turbine blades of more than 80 meters in length are being loaded for delivery to Zhangye more than 200 kilometers away.

'The generation has been increased from the original 2 MW to 6 MW with this set of blades,' said Han Xudong, Director of General Management at Gansu Chongtong Chengfei New Materials Co., Ltd. For power generation companies, this means more power is generated at a lower cost. 'Today, the wind turbine blades produced in Wuwei have been sold to many provinces. In 2021, orders of 1,200 sets were delivered with a total value of CNY750 million.'

It benefits enterprises and increases the local people's income. 'The manufacturing of wind turbine blades is labor-intensive, a set of blades requires the close cooperation of more than 200 people,' said Han Xudong. It has provided more than 900 jobs for people from nearby villages and towns. With 3 months of training, they can get started with the job and each earns CNY4,500 on average per month.

Li Yumei, a villager from Zhaizi Village, Fengle Town, Liangzhou District, Wuwei, joined the company as a worker in 2015 for the first process of blade manufacturing. 'The job is not strenuous and everyone can get started after training. Now I can earn more than CNY5,000 per month. The more skillful you are, the more you can earn.'

'Last year, our villagers were paid more than CNY100,000 in total for photovoltaic power generation,' said Wang Shouxu, deputy director of the villagers' committee of the Hongguang Xincun Village, Liuba Town, Yongchang County, Jinchang. Some of the income is used for the construction and maintenance of village-level public welfare undertakings and some to pay wages of public welfare jobs. Yongchang County was listed as a pilot county for promoting distributed photovoltaic power in Gansu Province in August 2021. The planned installation capacity is 0.27 GW and the benefited farmers are expected to increase their income by CNY1,000 per year.

According to the CPC Gansu Provincial Committee, Gansu will focus on the development of the clean energy industry and speed up the construction of the Hexi Corridor clean energy base so that the new energy industry will gradually become a main driver and a pillar of the local economy.

Source: People's Daily