The Kela photovoltaic (PV) power station, the world's largest and highest-altitude hydropower and PV complementary power station. (Photo/Courtesy of PowerChina Chengdu)

The Kela photovoltaic (PV) power station, the world's largest and highest-altitude hydropower and PV complementary power station goes into operation for power generation on Sunday.

The official running of the power station located in the Yalong River Basin, Southwest China's Sichuan Province marks the first time that the complementary operation between hydropower and PV has been elevated to a capacity of over 1 million kilowatts, as China strives to ensure energy security and achieve its dual carbon goals.

The project covers an area of around 16 million square meters, which is equivalent to 2,000 standard football fields. PowerChina Chengdu Engineering Co (PowerChina Chengdu) is responsible for the surveying, design, procurement, construction, commissioning, grid connection, and power generation for one third of the project.

The company is also taking the lead in the overall coordination of the PV power station.

The instability, fluctuation, and intermittency of PV power generation has a certain impact on the safety of the power grid. Combining solar and hydro power is considered an effective way of making it more stable, the project's chief design engineer Wu Di said.

The electricity generated by the solar panels will be connected to the Lianghekou hydroelectric power station, which was designed by PowerChina Chengdu, and then integrated into the power grid.

The project developer has gone through enormous challenges in order to complete the project.

Located in the western part of Kela in Yajiang county, with an altitude ranging from 4,000 to 4,600 meters, the project's highest point is nearly 1,000 meters higher than Lhasa, the capital city of Southwest China's Xizang Autonomous Region.

The segment undertaken by PowerChina Chengdu is the one with the highest altitude, largest scale, largest area, and most complex terrain, project manager Li Tao said.

The land portion comprises 92 percent of the segment, with pile types accounting for 75 percent and support bracket types making up 83 percent, Li said, adding that this particular segment also involves the most significant challenges due to its high altitude, extensive scale, expansive area, and complex terrain.

PowerChina Chengdu took on the planning responsibilities for the Kela project in 2016, with feasibility design work commencing in 2021 and construction officially beginning in July 2022.

Throughout the construction process, the project has encountered various challenges, one of which is the low oxygen levels caused by its high altitude. The project site experiences oxygen levels that are 50 percent lower than those in plain areas.

Other challenges, including frequent extreme weather conditions such as strong winds, heavy snowfall, freezing temperatures, as well as tight deadlines, have all posed a severe test for the engineering construction.

In the face of various obstacles, the team leveraged the experience gained from constructing numerous high-altitude projects, including the world's highest-altitude wind farm built by PowerChina Chengdu.

Working together with participating units, the construction team successfully established a precedent for large-scale winter construction of PV projects in extremely high-altitude regions with the Kela project, Li said.

Once operational, it is estimated that the project will save over 600,000 tons of standard coal annually and reduce carbon dioxide emissions by more than 1.6 million tons, a significant contribution to the rapid development of the new energy industry in the region.

As a pioneer in clean energy, PowerChina Chengdu has been actively involved in the surveying and planning of energy resources in the Yalong River Basin, including water, wind, and scenic resources, totaling over 100 million kilowatts.

With the completion of the Yalong River Energy Base, it will become one of the world's largest green, clean, and renewable energy bases.

In addition to playing a demonstrative and leading role in achieving the goals of peak carbon emissions and carbon neutrality and optimizing the national energy structure, the project is also driving the development of industries such as agriculture, animal husbandry, tourism, and transportation in ethnic minority regions.

During the construction process, PowerChina strives to employ as many local workers as possible.

Penpa Tsering, a local resident, who participated in the new project, said, "In the past, people used to make their living mainly through herding and going out for work. But things have changed, and now they can work right in their own neighborhood, earning an income and learning new skills at the same time."