Dammed If You Do
China’s move to dismantle small hydropower plants due to ecological damage has led to concerns over new safety issues and its carbon emission commitment
On July 23, the water resources bureau of Sichuan Province announced it had inspected 5,131 small hydropower stations. Among them, 1,360 stations or about 26.5 percent are categorized as those needing to be “phased out,” including 1,012 stations that were demolished by the end of 2020. In the meantime, necessary modifications were made to 3,528 small hydropower stations.
The move is part of a national drive launched in 2018 to curb the development of small hydropower stations, those with a capacity of less than 50 megawatts. China had an estimated 47,000 small hydropower stations by the end of 2015, with a combined generating capacity of 75 gigawatts, accounting for about a third of China's total hydropower capacity.
Rampant Growth
Large-scale construction of small hydropower stations started in the 1990s, when economic reform and liberalization led to increasing demand for water and electricity. In rural regions where access to power is limited, there was unchecked growth in small hydropower installations.
By the end of 2007, more than half the 2,851 counties in the Chinese mainland had at least one small hydropower station in their jurisdiction, and about 600, 21 percent of all counties, depend on them for power supply.
But as China established a more robust national grid system, reaching remote corners of the country, the sector came under stricter regulation. In December 2009, the Ministry of Water Resources issued a notice ordering safety to be strengthened at small hydropower stations.
More recently, as building an “ecological civilization” is a major policy priority, along with increased public awareness of environmental issues, the government turned its attention to the ecological impact of small hydropower.
According to an inspection report released by the National Audit Office in 2018, among 24,100 small hydropower stations in 10 provinces and municipalities along the Yangtze River Economic Belt (YREB) it investigated in 2017, at least 930 were constructed without environmental appraisal. As these stations intercept a large volume of water, 333 rivers in the region have dried up either permanently or periodically, with the total length of the completely dried-up river sections exceeding 1,017 kilometers, said the report.
In 2018, China issued a decree requiring governments in 10 provinces and municipalities in the YREB to clean up or rectify all small
hydropower plants by the end of 2020 to protect and repair the river ecosystem.
In 2019, China banned construction of small hydropower plants in forest parks, scenic areas, habitats for rare fish and other “ecologically fragile” zones, as well as in regions where there is an electricity surplus.
In April, the Ministry of Water Resources announced completion of the rectification project in the YREB. Among some 25,000 small hydropower stations in the region, more than 21,000 stations had adjusted the water flow to meet ecological requirements, 3,090 were dismantled, and 903 are scheduled for demolition.
In total, more than 90,000 kilometers of rivers and waterways have been restored, and four provinces have established a long-term mechanism to monitor the operation of these stations, said the ministry.
Controversial Campaign
Despite the claimed success, the “rectification” campaign has been controversial from the start. The China Society for Hydropower Engineering, an academic research group, criticized the mass closures of small dams, arguing that small hydropower plays an important role in China's clean energy transition and that the detrimental ecological impact of small hydro is exaggerated.
“While the unchecked development of small hydro is a major factor behind the environmental problem of many rivers, many of the existing problems can be solved by strengthening regulation and conducting technological upgrades of existing stations,” said Wang Yinan, a research fellow at the Development Research Center of the State Council.
Wang said that in implementing the rectification campaign, some local governments resorted to dismantling all small hydropower stations in their jurisdiction, rather than making science-based assessments of each dam, which may create new problems.
In Xi'an, capital of Shaanxi Province, 50 out of 52 small hydropower stations have or are scheduled to be dismantled. In six cities in the Qinling Mountains region including Xi'an, 251 out of 375 small hydropower stations, or 85 percent were dismantled or are scheduled to be dismantled.
According to an estimate from the Water Resources Bureau of Shaanxi Province, it will cost 8 billion yuan (US$773M) to demolish the designated small hydropower stations and compensate their private owners. As many of these power stations are in poorer mountain counties, local governments do not have the financial resources.
In Shaanxi's Zhouzhi County, the local government needs to pay 117 million yuan (US$18.1M) to a local company that owns three dams scheduled to be dismantled. By comparison, the county government's general revenue in the first half of 2020 was only 135 million yuan (US$20.8M). As there are still 29 small hydropower stations to be dismantled, the total costs go far beyond the county's affordability.
Given the huge financial costs of dismantling the generating stations alone, many local governments resort to simply dismantling power-generating installations and equipment without removing the dams and restoring river conditions.
According to a report in the Hunan Daily, among 86 small hydropower stations dismantled in Zhangjiajie, home to a UNESCO global geopark, 35 dams were deemed too important to local livelihoods, for example to provide irrigation or drinking water, and kept intact.
“If a hydropower plant poses an ecological problem, it's the dam that does that, not the power installations,” said Zhang Bingqin, who owns a hydropower plant in Xi'an, Shaanxi Province.
“It doesn't make sense to just dismantle power equipment,” Zhang noted.
Wang Yinan warned that by removing power installations, the dam structure would be subject to stronger impact of water flow, which poses a major safety threat. “Ninety percent of dam breaches were in non-powered dams,” Wang said.
“Power installations are an integral part of hydropower plants essential to maintaining its safety,” said Wang Yinan, “It's completely unscientific [to dismantle power equipment but leave the dam].”
Under Currents
According to Wang Yinan, as China has made new pledges to peak carbon emissions by 2030 and achieve carbon neutrality by 2060, authorities should rethink their approach toward the development of small hydropower.
In the past years, small hydropower plants have played a major role in curbing carbon emissions in China. In Hunan Province alone, hydropower output saves 15.34 million tons of standard coal per year, reduces CO2 emissions by 38.35 million tons, and cuts sulfur dioxide emissions by 20,000 tons, according to the provincial water resources bureau.
Wang warned the campaign aimed at phasing out small hydropower plants in the past couple of years has led to a policy bias against small hydropower plants in the media and among the public and local policymakers, which will have a major impact on the development of hydropower in China in the future.
According to the World Bank, while hydropower offers great potential, especially in the developing world, there are risks as well. China is among the largest of these countries when it comes to exploiting hydropower capacity.
“China has only exploited 44 percent of its hydropower, far less than the 80 percent of the developed world,” said Wang, “It remains an essential part of China's emission strategy if China were to deliver its commitment to increase the share of non-fossil fuels in its energy consumption to 25 percent by 2030.”
As for existing plants, Wang said authorities should consider turning them into a network for pumped hydroelectric energy storage – storing water in a high reservoir and releasing it to generate power. This can play an essential role in grid stability as the proportion of unstable wind and solar power gradually increases.
“Ultimately, China needs a long-term plan regarding the development of the small hydro sector, making it an integral part of China's energy system oriented at achieving carbon peaking and carbon neutrality,” Wang said.