What is Micro Hydro?

Small hydropower (small hydropower for short) currently does not have a consistent definition and demarcation of capacity ranges across the world. Even in the same country and in different periods, the standards are not the same. Generally speaking, small hydropower can be divided into micro, small and small 3 grades according to installed capacity. Some countries have only one grade, and some countries are divided into two grades, which are quite different. According to China's current regulations, small hydropower stations with installed capacity less than 25,000 kW are called medium-sized hydropower stations with a capacity of not less than 25,000 kW and less than 250,000 kW; large hydropower stations with a capacity of more than 250,000 kW.

The technology that converts kinetic energy in water into other forms of energy has been a fully formed process, and has been applied to power generation efficiently for centuries. As a result, it has become one of the main means of generating electricity in many countries, especially in less developed countries in Africa, Asia and South America. This technology first appeared on a small scale and served several communities near the generator, but with the expansion of relevant knowledge, it has been able to perform large-scale power generation and long-distance transmission. Large-scale hydroelectric generators use vast reservoirs, these

The power industry is the leading industry of the national economy. Energy is also an urgent issue in our country. Rural electrification is an important aspect of agricultural modernization, and small hydropower resources across the country are a good source of energy to provide rural electricity. Over the years, with the support of the national and local levels, we have mobilized various forces, closely integrated water management and electricity generation, and small hydropower generation has achieved vigorous development. China s small hydropower resources are quite abundant. According to a national organization s survey of rural hydropower resources (I0MWsingle-station installed capacity50MW), the country s rural hydropower resources development capacity is 128 million kW. Rivers and 0.5MWsingle station installed capacity <50MW) were 652l0MW, supplementary review increased by 62790MW.

Rural small-scale hydropower has developed a lot in recent years. On the basis of newly installed capacity exceeding 5,000MW in 2005, it has reached a new level in 2006. According to preliminary statistics, the annual new installed capacity will exceed 6000MW and the annual power generation It has reached more than 150 billion kW · h, with a construction scale of 20,000 MW. By the end of 2006, the total installed capacity of rural hydropower had reached 50,000 MW, accounting for about 37% of the national installed capacity. Rural hydropower has become an important part of the national power supply. Of the more than 100 million kW of hydropower installed capacity in China, more than 28,000 MW belong to small hydropower stations with less than 50 MW at a single station, with about 43,000 units, accounting for 33% of the total hydropower capacity. Small hydropower is rich in resources. It plays an active and effective role in solving the problem that large power grids such as the vast rural areas and remote mountain areas are difficult to spread to the area. Small-scale hydropower investment is scattered, there are many private and collective investors, easy financing, relatively simple technology and equipment, short construction period, and it is a renewable energy that cannot be ignored. The state has included small hydropower in the support of preferential policies for renewable energy. During the Tenth Five-Year Plan period, the task of rural electrification construction has been fully completed. By the end of 2005, a total of 22 counties across the country had installed hydropower capacity of more than 180MW, including 6 counties in Guangdong Province, 6 counties in Sichuan Province, 4 counties in Yunnan Province, 3 counties in Fujian Province, 2 counties in Zhejiang Province, and 1 in Chongqing City. county.

The "Eleventh Five-Year Plan" should actively promote clean energy technologies such as small hydropower generation, continue to promote the construction of hydropower rural electrification, and contribute to the construction of a new socialist countryside. According to the plan, 400 counties nationwide will continue to choose electrification construction, and through further development of rich rural hydropower resources in mountainous areas, the construction of higher standards of hydropower rural electrification counties corresponding to the new socialist countryside. At present, the construction of hydropower and rural electrification counties in the Eleventh Five-Year Plan has officially started, and a new round of electrification construction is taking place in various places. Small hydropower plays an important role as rural electrification construction. Rural electrification has driven rural mechanization construction and promoted district (county) industrialization. In the past, many districts (counties) had any industry. With the development of small hydropower, it is possible to set up agricultural machinery,

For small hydropower stations, they have their own characteristics, mainly in the following aspects:

(1) The scale of the power station is small, the project is simple, and it has local characteristics.

(2) Small hydropower equipment is relatively simple, and many can be ordered nearby.

(3) Generally, small-scale hydroelectric power generation should not be transmitted over long distances, but it should be delivered to local use.

(4) The small hydropower grid has a small capacity, a small power generation capacity, and a small and dispersed load.

(5) Small hydropower buildings and equipment are small and simple.

(6) Due to the small scale of the small-scale hydropower generation, there are few problems of flooding and immersion.

According to the above characteristics of small-scale hydropower generation, it can be known that small-scale hydropower generation has strong local and mass characteristics. Planning and construction of small-scale hydropower must control the scale, do what we can, use local materials, apply applicable technologies, and focus on connotation expansion, and expand the installed scale with load growth. Small-scale hydropower generation can be jointly organized by individuals or several farmers, or collectively or by townships. It can also be joint ventures or joint ventures by prefectures, counties, and other regions. They can be constructed in stages, from small to large, from low to advanced. In fact, with the strong support of the state, China's small hydropower generation has relied on local human, material, and financial resources to develop and mobilize the enthusiasm of the local, county, and township people to flourish. In order to consolidate and protect the enthusiasm of the people for water management and power generation, the construction of small hydropower plants must pay more attention to practical results and must act in accordance with natural and economic laws. The planning and design of small-scale hydropower must be based on reliable hydrological and power load data, and strive to balance electricity and electricity. We must avoid the kind of one-sided pursuit of digital indicators of installed capacity without considering economic benefits. Because the installed capacity is too large, electricity cannot be generated during the dry season, and floods are absent or difficult to use during the flood season. As a result, the utilization rate of the equipment must be low, and the backlog of funds has caused the planned electricity use and economic income to fall. It affected the people's production and life, and dampened their enthusiasm for electricity. ^[2]

In East Africa, much of the potential of hydropower has not been fully tapped because the development of this technology has become increasingly expensive for the region's economic development. For example, the Kenyan government stopped development of hydropower stations in 2005 because the project failed to meet even the lowest cost development standards. If the electricity generated by this project is put into use, its cost will definitely be higher than the current electricity cost of other hydropower equipment. Unfortunately, when the decision was made to start the project, the government had already invested heavily. If the government can shift the focus of its energy development policy from large hydropower development to small hydropower development, then such waste of limited financial resources is likely to be avoided. There are many constant current rivers in East Africa, and their volume flow rates are not sufficient to support the operation of large hydropower equipment, but some small hydropower equipment can be established at a level of affordable cost. Many places suitable for this type of development have been discovered, and there are many other similar places nowadays, which are evenly distributed throughout the region, but no research has been carried out on their usability. Some related research in known places is mainly carried out by some non-governmental organizations, environmental scientists and some individual researchers, and the government should be responsible for conducting a detailed investigation of the situation to consider it as a willing investor The department that provided the relevant information did not take any relevant action. The fact that large and medium-sized hydropower stations can provide the region with a large amount of power is not false, and the power they provide is undoubtedly clean energy. However, time has changed, and we have to develop such technologies more adequately. Facing new problems.

The potential of hydropower is still there, but as demonstrated in the Kenyan case and the Uganda's Bugagali struggle, the establishment of large hydroelectric dams is too expensive and raises a number of environmental issues, some of which The study also needs to take into account ecological, cultural and biodiversity reasons, and we need to protect some of them: Obviously, there are many methods for large-scale hydropower technology, but most of them have environmental deficiencies, so some can Through rational planning to effectively avoid these energy technologies that may have a negative impact on the environment, consideration should be given to putting them into use. So it is obviously wrong to completely stop the development of hydropower technology, because there are some hydropower technologies that can be put into use under reasonable environmental and ecological guidance, and small hydropower systems are the best choice. Although the management of large-scale, state-controlled hydropower plans has suppressed the real demand for electricity to a certain extent due to the implementation of unreasonable policies, they have also been proven to be huge losses due to poor performance A viable business option. Recent reforms aim to correct the above, but it also reflects that it seems impractical to completely privatize these devices, because after all, there are issues related to national security that need to be considered. In summary, in East African countries, it is unlikely that the power of the individual sector in power supply will exceed the current limits, unless it is in this situation that the development of small hydropower plans is selected, in order to grasp the silver lining. At the same time, it is gratifying that there are currently a large number of small hydropower technology methods to choose from to match different river flow conditions. Some of these hydropower equipment include low-pressure heads, high-pressure heads, and free-flowing small hydropower stations. The generator has almost no impact on the environment. They also provide a number of advantages, such as high flexibility, the potential to maintain low levels of electricity costs, and high levels of social and cultural acceptability. Not only that, they also have low installation and management costs, and use only a simple distribution Can fully meet local needs. ^[1]