Energy performance of wind power in China: A comparison among inland, coastal and offshore wind farms

China has the largest wind power installation across the world due to the tremendous inland wind capacity and the government has begun to pay much more attention to develop offshore wind power in recent years. During the shift from inland to offshore, it is very important to identify the difference of energy performance between them. This paper establishes 4 indicators; energy consumption intensity (EI), energy payback time (EPT), energy payback ratio (EPR) and energy return intensity (ERI) to measure the energy performance of wind farms. Meanwhile, coastal wind farms are introduced as a smooth transition cases from inland to offshore wind farms. Each of the 8 farms for inland, coastal and offshore wind are taken as the examples to assess. The results show that inland and coastal wind farms have the similar energy performance, which pose significant difference with that of offshore wind farms. Based on the relatively lower EI, EPT and higher EPR, land-based inland and coastal wind farms are better for energy efficiency. From the energy performance route of wind farms, the energy performance strength of offshore wind farms only appear after 9.2 years of operation when compared to the land-based wind farms. Therefore, it is wise to set a long-term moderate target for offshore wind power development in China, just as the highest ERI of offshore wind farms can only be obtained in a long-term period.