
This undated file photo shows a visitor trying a gadget to learn about the process of power generation through waste incineration in the Heimifeng environmental protection park in Changsha City, central China's Hunan Province.

Staff members monitor the operation of facilities at the central control room of the Heimifeng environmental protection park in Changsha City, central China's Hunan Province on April 22, 2026.

This undated file photo shows a view inside the Heimifeng environmental protection park in Changsha City, central China's Hunan Province.

Staff members operate mechanical arms to transport waste into the incinerator in the Heimifeng environmental protection park in Changsha City, central China's Hunan Province on April 22, 2026.