To Efficiently Constitute Integrated Power System in China

Formation of national integrated power system should not be simply interconnected for the benefit of reducing emergency reserve and peak leveling, but should consider the 100 GW hydropower already constructed and the optimal dispatching and compensation regulation. In last 50 years, because of 95% firm power output designed for hydropower projects, it has caused the serious situation in the hydropower dominated Sichuan Province suffered with power shortage of 1000 MW in last winter and this spring; as well as only 1/3 hydropower capacity in Guangxi Province can be effectively worked. To solve this problem, the paper suggests strong north to south tie-lines connecting the 3 bulk power channels of "power transmitting from west to east", which yield benefits on: 1) increasing system total firm power output to 100%, also the system total firm power output will be greater than the summation of firm power output of individual hydropower stations, which greatly promote power reliability. 2) because compensating regulation yields nationwide capacity benefits of about 8 GW, corresponding to an investment saving in thermal power higher than the investment in national integrated power system. 3) in addition to compensating regulation, it can also send more hydropower to Guangdong and Guangxi, reduce coal transportation from north to south and coal import, thus improve power supply security