Why the Wind Curtailment of Northwest China Remains High
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sustainability Article Why the Wind Curtailment of Northwest China Remains High Guoliang Luo 1,2,*, Erli Dan 1 ID , Xiaochun Zhang 1 and Yiwei Guo 1 ID 1 School of Economics and Management, North China Electric Power University, Beijing 102206, China; [email protected] (E.D.); [email protected] (X.Z.); [email protected] (Y.G.) 2 Beijing Key Laboratory of New Energy and Low-Carbon Development, North China Electric Power University, Beijing 102206, China * Correspondence: [email protected] Received: 5 January 2018; Accepted: 6 February 2018; Published: 24 February 2018 Abstract: The total grid-connected installed capacity of wind power in northwest China has grown from 16,260 MW in 2013 to 43,290 MW in 2016; an increase of 88.7% each year. However, this region has suffered from increasingly serious wind curtailment since 2014, and the wind curtailment amount accounts for nearly a half of China’s total. The wind curtailment rate of Gansu Province, Xinjiang Uygur Autonomous Region and Ningxia Hui Autonomous Region in this area has increased and remains high. This paper constructs an analytical model to explore the reasons of the high wind curtailment of these three provinces from the four aspects of the wind power supply capacity, demand, grid transmission capacity, power system flexibility and market mechanism and laws. The results show that the relationship between the wind energy distribution and supply and the local load is incompatible, which is the source causing the high wind curtailment in northwest China. On the one hand, the game between the local government and developers has driven the development of wind power bases. On the other hand, the electricity sector is growing slowly and oversupply of electricity is seen in many areas of China. The wind power grid of northwest China not only faces limit of grid transmission capacity, but also constraint of insufficient flexibility of the electricity system. Presently, China has not set up a market mechanism and subsidy mechanism for the peak load adjustment, thus the thermal power companies lack motivation to voluntarily adjust the peak load. Moreover, the regional segregation and market barriers are also obstacles for the wind power outward transmission. Keywords: northwest China; wind curtailment; transmission capacity; power system flexibility; penetration rate; accommodation; market mechanism 1. Introduction In 2008, China’s wind power started to grow rapidly, marked by the approval of a 10,000 MW wind power base in Jiuquan, Gansu Province, opening a new chapter of the new energy construction of China [1]. Since then China’s installed capacity of wind power continued to rise, showing a “blowout” situation with construction of eight 10,000 MW-class new energy bases being approved, forming a mode of large-scale, concentrated development and long-distance transmission [2]. The total installed capacity of wind power connected to the grid was 148,640 MW in 2016, which is 16.7 times that of 2008 [3] (Figure1), creating a miracle in the history of the new energy development of the world. While making great achievements, China saw a growing problem of wind curtailment [4]. It has become a focus of the whole society on how to improve the new energy utilization rate and reduce the electricity being curtailed. Sustainability 2018, 10, 570; doi:10.3390/su10020570 www.mdpi.com/journal/sustainability Sustainability 2018, 10, 570 2 of 26 Sustainability 2018, 10, x FOR PEER REVIEW 2 of 24 Figure 1. Development of the grid-connected installed capacity of wind power between 2005 and 2016 [3]. Figure 1. Development of the grid-connected installed capacity of wind power between 2005 and 2016 [3]. The electricity system simultaneously realizes power generation, supply and consumption and the electricity load shows obvious time-variant characteristics. The peak-valley difference of the powerThe grid electricity in northwest system China simultaneously has exceeded realizes 30%, and power shows generation, a growing supply trend. and A basic consumption condition and for the electricity loadsystem shows to run obvious steadily time-variant is that thecharacteristics. system adjustment Thepeak-valley capacity must difference be higher of thethan power load gridfluctuation in northwest [5]. 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