China's central government of the day extended its sphere of influence to Changji with the establishment of the Protectorate of the West Region (Xiyu Duhufu) in 60BC during the Western Han Dynasty (206BC-24AD). In 1884, a province was set up to administrate Xinjiang, and the Changji region belonged to Dihua Fu. Changji, which gets 2749 to 3090 hours of sunshine per year, is rich in potential solar energy. In addition, Changji is also replete with oil and natural gas resources. There are four oilfields are under construction, and proven reserves of petroleum amount to 150 million tons, while natural gas reserves total 30 billion cubic meters.