Fig. 1: Wind Farm in Local Xinjiang Province. (Source: Wikimedia Commons) |
China has emerged as the world's leading energy user with a demand that has nearly doubled since the turn of the 21st century. [1] To leverage this demand as an opportunity to expand renewable energy infrastructure, China pushed forward its National Renewable Energy Law of 2006. The law provided financial incentives for renewable research, development, and manufacturing. [1] Beyond addressing the pressing energy need, the new legislation would reduce foreign energy dependence as well as the nation's environmental footprint. At the 2009 World Economic Forum, China's Premier Wen Jiabao reaffirmed this position, stating, "China will accelerate the development of a low-carbon economy and green economy so as to gain an advantageous position in international industrial competition." [2] With the public support and financial backing of the government, China has since built more than 92,000 wind turbines throughout its provinces (see Fig. 1). For instance, the Jiuquan Wind Power Base alone consists of 7,000 turbines scattered throughout the Gobi desert. [3]
Despite China's rapid growth in wind generation capacity, wind power still accounted for less than three percent of all electricity generation in 2013. [2] The lackluster effect of this wind energy "revolution" stemmed from issues with grid connection and curtailment. China's Renewable Energy Industries Association reported that up until 2012, nearly one third of wind turbines were still not grid-connected, leaving many of these wind farms frequently idle. [2,3] Compounding connectivity issues, grid operators were avoiding wind-generated power in a phenomenon called curtailment. Due to an overproduction of energy across different sectors, grid operators were frequently abandoning wind generator power in favor of other sources like coal power. [4] In many of China's famous "10-GW wind power bases", typically located in more remote areas, curtailment rates reached 40 percent. [4] By comparison, curtailment rates range between one and four percent in the United States. [2]
An inherent feature of particular renewable energies such as wind and solar power is intermittency. Naturally, no energy can be produced when there is no wind. Unfortunately, modern grid technology affords minimal energy storage capacity. As such, a reserve power source needs to balance the wind-generated supply such that the grid can match consumer needs in the face of weather fluctuations. [1] China has typically relied on coal as this reserve power. However, coal-fired power plants are slow to shutoff and restart, typically running at a steady baseload. [2] The rigid nature of these plants thus creates compatibility issues with the sporadic behavior of the environment. On this front, one might look to Denmark for inspiration, which relies on hydroelectric power, a more adaptable source, to balance the intermittency of wind energy. [2]
In recent years, China has acknowledged policy shortcomings and made efforts to make wind power more viable role player in the energy sector. In particular, China has raised rates of grid connectivity to wind farms to 88 percent as of 2014. [2] Although curtailment rates still remain high, the government has committed to improving and leveraging weather forecasting technology to better balance reserve energy sources with intermittent wind energy. [4] If successful, these reforms could further capture the potential of China's wind farms and solidify the country's position as a global leader in renewable power.
© David Lin. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
[1] D. Zhang et al., "An Integrated Assessment of China's Wind Energy Potential," MIT Joint Program on the Science and Policy of Global Change, April 2014.
[2] I. Koch-Weser, "China's Wind and Solar Sectors: Trends in Deployment, Manufacturing, and Energy Policy," US-China Economic and Security Review Commission, 9 March 15.
[3] E. Koufakis, "The Jiuquan Wind Power Base," Physics 240, Stanford University, Fall 2017.
[4] M. R. Davidson et al., "Modelling the Potential for Wind Energy Integration on China's Coal-Heavy Electricity Grid," Nat. Energy 1, 16086 (2016).