China creates “great photovoltaic wall” in the country’s desert

In Chaideng Village, Ordos City, 3.46 million blue solar panels cover 30 million square meters, transforming the endless sands into a shimmering “photovoltaic sea.” The solar power base is part of a Chinese solar-powered desert restoration project known as the “photovoltaic great wall,” which stretches along the northern edge of the Kubuqi Desert.

This grand project, while not able to rival the real Great Wall in length, is planned to stretch for about 400 kilometers with an average width of 5 kilometers, said Liu Tianyun, deputy director of the Ordos forestry and grassland bureau.

It will set a new record in terms of area for photovoltaic farms in China and will have 100 million kilowatts of installed capacity upon completion, Liu said. So far, the city has installed 5.42 million kilowatts of solar power on more than 200,000 mu (13,333 hectares) of sand area.

The Kubuqi Desert has wide, open lands that are perfect for solar power plants. The region has abundant solar resources, with 3,100 hours of sunlight per year.

In addition to generating energy, local solar projects have also proven useful in mitigating the area’s frequent and intense sandstorms and desertification.

The project took an innovative approach, with energy-generating solar panels mounted on top, allowing plants to grow in the soil and small farm animals to graze beneath the panels.

Solar panels can reduce groundwater evaporation by 20% to 30%, while providing shade and reducing wind speeds, all while supporting plant growth. With plants and animals thriving in the shade, this approach yields both economic and ecological benefits.

In some arid areas, solar-powered drip irrigation is also adopted to green desert landscapes in China. To adapt to the challenging conditions of desert environments, innovations in photovoltaic modules have been introduced.

The photovoltaic modules use bifacial technology and high-efficiency cells that can capture sunlight from both sides, taking advantage of the high reflectivity of sandy surfaces to increase power generation by approximately 8%.

The service life of the modules has also been extended from 25 to 30 years after adopting double-glass encapsulation materials. The minimum clearance between the PV panels and the ground has been adjusted to about 2.5 meters, providing ample space for people and machines to move easily for agricultural work.

Ordos City, also known for its abundant coal resources, has several large coal mines scattered across the Kubuqi Desert. Treated drainage water from the coal mines is piped from these mines to the solar power base and used to clean the solar panels and water the plants.

Standing beneath a solar panel array in Chaideng village, Zhang Xiuling, deputy mayor of Ordos, said that by planting crops in the sand and covering them with solar panels, they are essentially creating a double-layer “shield,” keeping the quicksands firmly at bay.

With information from Xinhua.