The unexpected things often determine the results of energy experiments or expectations. It is also axiomatic that nothing is ever perfect in this business. For proof of those two thoughts, consider what has been happening in China the past several months and how it has affected what was supposed to be one of the best examples of energy alternatives.
A severe drought that has plagued southwest China since August 2009 has caused a painful shortage of water in the region. And that drought is crippling the region’s hydroelectric power generation sector. But the dams themselves are making the drought even worse because their operators are focused almost solely on power generation rather than water conservation.
A view of a dried-up pond at Haizi town in Luliang in southwest China's Yunnan province. A severe drought hit southwest China, leaving more than 16 million people and 11 million livestock with drinking water shortages. Photo by Li Huang: AP
China’s hydro power sector, which had been hailed for its low-carbon properties, and of course, aided by big government subsidies, has been developed at a fast pace. In 2009 alone, 20 GW of new capacity was added in China and the national total hydroelectric capacity reached 197 GW, comprising 22.5 percent of the total national power capacity of 874 GW. The National Energy Commission has been considering increasing the total hydroelectric power capacity to 300 GW by 2020. The water-abundant and mountainous southwest China, including Yunnan, Guizhou and Guangxi, Sichuan Provinces and Chongqing District, has always been the preferred site for hydroelectric power. By the end of 2009 hydroelectric power capacity in this area amounted to 44.7 percent of the national total.
In August 2009, the hydroelectricity generated from this area was 30,640 gigawatt-hours. But by last month, that generation had fallen to just 9,540 GW-hours, a 69% decrease. Although affected by the season, this kind of decrease was unprecedented. Overall hydroelectricity from the southwest power plants has been reduced by 40 percent due to the drought.
In Yunnan Province, the generated power has only been less than 20% of normal. The situation in Guangxi Province was even worse, where some 90% of the hydro capacity is considered “paralyzed.” Under such circumstances, all coal-fired power plants have been in full-blast operation to keep the lights on. Since the capacity of coal-fired power plants is very limited in the region, electricity shortages are common, as are blackouts.
Guangxi has over 5,000 surface water reservoirs which are intended to prevent flood and remedy drought for agriculture. In addition, by 2008, the province had about 2,300 hydroelectric power plants. And more have been built. As soon as a power plant is built, water has to be discharged to generate electricity, no matter whether the downstream needs water or not for agriculture or human consumption. The drought has lasted more than 6 months and the water level in many reservoirs has been dangerously low. But the hydro plants continue discharging water for power generation.
Some reservoirs have become dead water pools or dried out altogether. As a result, about 23 million people in the region are now short of drinking water. The local people complained that if the discharge of water from the reservoirs has not been following the needs of the power plants, the ill effect of the drought might not be so severe.
In Guizhou Province the water resource has never been a problem. However, except for the hydroelectric power plants, nothing has been invested in any irrigation system and no infrastructure has been built to tap the region’s abundant underground water resources. When the drought hits, the small surface water pools dry out, causing drinking water shortages. The ongoing drought has also gravely affected agricultural production, and has caused price increases for rice, sugar, tea, etc.
The ill effects of the drought may force China to think the next time the country embarks on a new push for even more hydroelectric power plants.
By Xina Xie and Michael J. Economides
Source: Energy Tribune