A few days ago, the Ministry of Water Resources released the list of the first batch of green small hydropower stations, and 44 hydropower stations were recommended as the 2017 Green Small Hydropower Stations. "In the future, new power stations and existing power stations will all be constructed in accordance with green small hydropower standards to realize the greening of the whole process of small hydropower planning, design, construction, operation and management." Hydropower construction work site meeting said.
From power generation to comprehensive utilization, ecological priority
Small hydropower is an important clean and renewable energy. According to statistics, the installed capacity of small hydropower stations in China is nearly 78 million kilowatts, and the annual power generation capacity is 268.2 billion kWh, accounting for 1/4 of my country's hydropower installed capacity and annual power generation. The completed small hydropower stations have made important contributions in solving the electricity consumption of the population in areas without electricity and power shortage, and promoting river governance, ecological improvement, and environmental protection. But at the same time, there are still many weak links in the planning, design, construction, operation and management of small hydropower in some areas.
Lu Guihua said that at present, people's needs for river functions are increasingly diversified. In the past, most of the small hydropower projects were mainly based on power generation. Now more and more small hydropower projects not only need to generate electricity, irrigate and supply water, but also meet the needs of ecological water and landscape water, and provide hydrophilic recreational products. "In response to the people's new expectations for the change of river function requirements, we must pay attention to solving the problem of unbalanced and insufficient small hydropower development in the process of small hydropower development, adjust the functions of small hydropower stations according to the adjustment of river function positioning, and focus on expanding and improving comprehensive utilization. Provide more and better water resources comprehensive utilization products and services, so that ordinary people can feel the achievements of green small hydropower development." Lu Guihua said.
Based on this, the Ministry of Water Resources has accelerated the transformation of the development concept, proposed the limited, orderly and paid development and utilization of hydropower resources, promoted the construction of green hydropower, and attached importance to the role of small hydropower in protecting the ecological environment. Taking efficiency enhancement and capacity expansion as the starting point, highlighting river ecological restoration. At present, nearly 3 billion yuan of central financial incentive funds have been allocated, and some projects have been completed and played a role; , to implement the concept of green development, more than 3,200 small and medium-sized river hydropower development plans have been revised, and the rural hydropower layout has been further optimized.
Liu Zhongqi, deputy director of the Guangxi Water Resources Department, said that when the Water Resources Department compiled the "Small and Medium-Sized Hydropower Development Plan" in 2016, there were 794 small and medium-sized hydropower stations initially included in the plan. After repeated demonstrations, 245 power stations in sensitive river sections such as nature reserves, scenic spots, and ecological public welfare forest reserves were excluded; 27 power stations were subject to conditional approval and restricted approval during the planning period due to poor efficiency or disputes. , strict approval or non-approval; a total of 522 small and medium-sized hydropower stations were finally included in the planning report. "In the process of planning preparation, emphasis is placed on water energy resource management and river ecological protection, from emphasizing full utilization of water energy resources to limited and orderly. development; from emphasizing the function of power generation to more emphasis on the comprehensive utilization, ecological functions and environmental benefits of hydropower stations”.
The establishment of green small hydropower station kicks off
The Ministry of Water Resources has put forward the guiding opinions on the development of green small hydropower, the guiding opinions on the ecological restoration of rivers through efficiency enhancement, expansion and transformation, and promulgated and implemented the "Green Small Hydropower Evaluation Standards" and other green small hydropower technical specifications. In June 2017, the establishment of green small hydropower stations officially kicked off, guiding the small hydropower industry to speed up the transformation of the development mode and take the road of eco-friendly sustainable development. According to the plan, by 2020, all power stations with an installed capacity of more than 10 megawatts per station, more than 1 megawatts within the national key ecological function zones, and supported by central financial funds will be established as green small hydropower stations.
Why carry out the construction of ecological hydropower demonstration zone? Jiang Ruhua, deputy director of Zhejiang Provincial Department of Water Resources, said that in recent years, the contradiction between power stations and environmental water use has become prominent. Restricted by historical factors, some diversion-type hydropower stations developed and built in the early stages of the province have phenomena such as cross-basin diversion and excessive closure, resulting in deflow of some river sections. As the public's requirements for water environment and water landscape are getting higher and higher, the contradiction between power generation of hydropower stations and water demand of downstream rivers is prominent. At the same time, the comprehensive benefits are not fully exerted. Most of the rural hydropower projects focus on power generation. With the development of economy and society, a single function will not be able to meet the needs of the public. Comprehensive benefits such as environmental governance will become the direction of hydropower development.
Since 2016, Zhejiang has built 24 ecological hydropower demonstration zones, 53 ecological restoration power stations, restored 24 rivers, restored 25 kilometers of dewatering river sections, built and rebuilt 3 ecological flow discharge gates, and built new ecological weirs. 37. Through various engineering measures and non-engineering measures, the construction projects of the demonstration zone have basically eliminated or alleviated the environmental problems of local river sections and even some river courses such as dehydration and water reduction caused by hydropower stations, improved the river bank environment, protected the ecology, and ensured the downstream Production and living, landscape and ecological water use have promoted the development of local leisure tourism.
Guangxi has perfected the ecological operation mode of cascade power stations. During the operation of the hydropower station, according to the principle of "electricity regulation obeying water regulation", the operation mode is adjusted, and the water volume is comprehensively dispatched according to the requirements of the ecological flow of the river. Formulate a joint dispatch plan for cascade power stations, and at the same time ensure reasonable power generation, make overall arrangements for the quantity, time, and flow rate of water storage and discharge, so as to ensure the connection of water levels and the smooth and stable water system. By accumulating abundance and making up for dry season, the downstream flow in dry season is effectively improved. The Wulixia Reservoir Power Station has formulated a gate scheduling operation mode, which is responsible for the irrigation task of 100,000 mu of farmland downstream and the needs of downstream ecological water. The Qingshitan Reservoir Power Station supplies 103 million cubic meters of water to the Lijiang River every year, depending on the tourism and navigation conditions of the Lijiang River and the drinking water needs of Guilin citizens, which effectively ensures the normal navigation of the Lijiang River cruise ships during the dry season and improves the water ecology of the Lijiang River Basin.
Go green from planning to operation
Xing Yuanyue, deputy director of the Hydropower Immigration Department of the Ministry of Water Resources, said that the green development of rural hydropower must first strengthen planning constraints and optimize the development layout. Newly built or renovated small hydropower stations must follow the approved regional spatial planning, comprehensive river basin planning, river hydropower resource development and other planning, and it is strictly forbidden to develop and construct small hydropower stations in ecological red line areas. Guided by the concept of green development, planning water resources demonstration and environmental impact assessment should be carried out, and small hydropower construction projects should be rationally arranged, and should be adapted to the carrying capacity of local water resources and the requirements of river ecological and environmental protection. According to the functional requirements of the river, it is necessary to investigate and evaluate the development layout, development scale, development method, construction and operation of small hydropower, and optimize and adjust the old power stations.
In the Jiufeng Reservoir in Jinhua, Zhejiang, the water quality reaches the surface water class II standard or above all year round. The lower reaches of Hou Daxi have an open channel, the water is gentle and crystal clear, and the vegetation on both sides is lush. An automatic water quality monitoring station has been built in the reservoir, and an automatic flow monitoring device has been installed in the tail water channel of the hydropower station to realize online monitoring of the water quality and ecological water release of the reservoir and ensure the downstream ecological water consumption. Pan Lusheng, director of the Jinhua Water Conservancy Bureau, said that in order to ensure the ecological safety of the rivers downstream of the city-level reservoirs, the city has established a compensation mechanism for the ecological water discharge of the municipal-level reservoirs and the profit and loss of power generation after the water discharge, which will compensate the Jiufeng Hydropower Station's ecological power generation profit and loss of 540,000 yuan per year. By sowing grass seeds and planting seedlings, 30,000 square meters of green were restored, and 186,000 fish fry were proliferated and released, effectively preventing soil erosion and improving the water quality of the reservoir.
Different from the Jiufeng Hydropower Station, the Kaizipu Hydropower Station in Shiquan County, Shaanxi Province is a runoff diversion power station. The completion of the power station ended the history of no electricity in the remote mountainous areas in the north of the county. The length of the water-reduced river section between the plant and the dam is 1.2 kilometers. In order to ensure the ecological flow demand of the downstream river and maintain the natural ecology of the river, an ecological unit with an installed capacity of 400 kilowatts has been built behind the dam. The power station adheres to scientific scheduling to ensure that the ecological units operate all year round, and the uninterrupted discharge of the ecological flow is not less than 10% of the average flow of the dam site for many years. "Although the installed capacity is not large, as long as we adhere to the road of green development, there is great potential in energy conservation and emission reduction, improvement of people's livelihood, and ecological restoration," said Guo Yiming, the representative of the hydropower station owner.
"Another aspect of the green development of small hydropower is to upgrade the operation and ensure ecological security." Lu Guihua said that it is necessary to transform or add uncontrolled discharge facilities, ecological units, etc., with rivers as a unit, to ensure the ecology of the river between the dams of small hydropower plants. Water demand; build hydrophilic dams, etc., to improve the water resources conditions in the river channels between the plants and dams in the diversion reach, and ensure the ecological health of the water in the river channels; for hydropower stations that have a great impact on the river hydrology during the dry season, improve the power generation scheduling method and promote seasonal restricted operation ; For small hydropower stations that cannot be repaired and transformed, they should be gradually shut down or withdrawn. It is also necessary to gradually establish a monitoring network for ecological water use of small hydropower stations. Through the cascade cooperation mechanism of the river basin, the whole river basin can cooperate to continuously ensure the ecological water demand and continuously improve the river ecology.