China leads the world in renewable energy generation, but an increasing amount of that power may go to waste if electrical grids cannot keep up, a Beijing-based business news site wrote. China’s energy resources are concentrated in more rural areas far from its population centers, and local grids don’t have the capacity to accommodate surging wind and solar power generation, Caixin reported.

The country is developing more ultra-high-voltage transmission lines to move power to the cities, but experts say their construction has been slow, leading to more clean power wastage. At the same time, total electricity demand in China is outpacing wind and solar power generation: Coal remains king.