D ou Zhenggang is a Chinese entrepreneur who made his fortune in the renewable energy sector, specifically in wind power. He is the chairman of Jiangsu Zhongnan Construction Group, a company that, in addition to its core construction business, has made significant investments in clean energy. His wealth is derived from his controlling stake in this diversified, publicly traded enterprise.

While Zhongnan Group has a long history in construction and real estate, it was its strategic move into operating wind farms that significantly boosted its valuation and the wealth of its founder. Dou has successfully built a substantial portfolio of wind power projects across China, capitalizing on the country's massive government-led push into renewable energy. His career illustrates a successful pivot from traditional industry to the booming green energy sector.