Electric power grids and power supply in China

General situation of power grids and power supply in ChinaAlong with the rapid growth of the generating capacity,thetransmission system has expanded correspondingly.In 1949,thetotal circuit length of the 33-220kV lines was 6475 km,and the totalcapacity of the corresponding step-down substations was 2 390MVA,among these,70% were of 33 kV.The 220 kV transmissionlines measured 765 km in length and the capacity of the correspond-ing step-down substation was 330 MVA.By the end of 1989,the totallength of the 35-500 kV lines reached 450 892 km,and the capacityof the corresponding step-down substations reached 371 380 MVA.