They might be referring to dependence on solar-powered water pumps to irrigate the green belt, or the use of a field of solar panels with vegetation underneath to break up wind-driven sand migration. Another source discusses the construction of meter-high earthen walls, though its unclear how widely that was done. They're planning on building more solar and wind there, and China's UHV (ultra-high-voltage) grid will allow that power to be shipped east to where demand is highest:

https://interestingengineering.com/energy/chinas-largest-des...

> "Further energy development is underway in the Taklamakan Desert. The China Three Gorges Corporation plans to build a massive energy project featuring 8.5 gigawatts of solar power and 4 gigawatts of wind energy, expected to be completed in four years."