HOME

TheInfoList



OR:

Small hydro is the development of hydroelectric power on a scale suitable for local community and industry, or to contribute to distributed generation in a regional electricity grid. Exact definitions vary, but a "small hydro" project is less than 50 megawatts (MW), and can be further subdivide by scale into "mini" (<1MW), "
micro Micro may refer to: Measurement * micro- (μ), a metric prefix denoting a factor of 10−6 Places * Micro, North Carolina, town in U.S. People * DJ Micro, (born Michael Marsicano) an American trance DJ and producer * Chii Tomiya (都宮 ち ...
" (<100 kW), "
pico Pico may refer to: Places The Moon * Mons Pico, a lunar mountain in the northern part of the Mare Imbrium basin Portugal * Pico, a civil parish in the municipality of Vila Verde * Pico da Pedra, a civil parish in the municipality of Ribe ...
" (<10 kW). In contrast many hydroelectric projects are of enormous size, such as the generating plant at the Three Gorges Dam at 22,500 megawatts or the vast multiple projects of the Tennessee Valley Authority. Small hydro projects may be built in isolated areas that would be uneconomic to serve from a national electricity grid, or in areas where a national grid does not exist.


Description

The use of the term "small hydro" varies considerably around the world, the maximum limit is usually somewhere between 10 and 30 MW. While a minimum limit is not usually set, the US National Hydropower Association specifies a minimum limit of 5 MW. In California, hydroelectric generating stations with a maximum capacity of less than 30 MW are classified as small, and are eligible for inclusion in the state's renewable portfolio standard, while hydroelectric generating stations with a higher capacity are classified as large and are not considered renewable. The "small hydro" description may be stretched up to in the United States, Canada and China. In India, hydro projects up to 25 MW station capacities have been categorized as Small Hydro Power (SHP) projects. Small hydro can be further subdivided into mini hydro, usually defined as 100 to 1,000 kilowatts (kW), and
micro hydro Micro hydro is a type of hydroelectric power that typically produces from 5 kW to 100 kW of electricity using the natural flow of water. Installations below 5 kW are called pico hydro. These installations can provide power to an ...
which is 5 to 100 kW. Micro hydro is usually the application of hydroelectric power sized for smaller communities, single families or small enterprise. The smallest installations are
pico hydro Pico hydro is a term used for hydroelectric power generation of under 5 kW. These generators have proven to be useful in small, remote communities that require only a small amount of electricity for example, to power one or two fluorescent ...
, below 5 kW. Since small hydro projects usually have correspondingly small civil construction work and little or no reservoir, they are seen as having a relatively low environmental impact compared to large hydro.


Growth

According to a report by REN21, during 2008 small hydro installations grew by 28% over year 2005 to raise the total world small hydro capacity to 85 gigawatts (GW). Over 70% of this was in China (with 65 GW), followed by Japan (3.5 GW), the United States (3 GW) and India (2 GW).Renewables Global Status Report 2006 Update
, ''
REN21 REN21 (Renewable Energy Policy Network for the 21st Century) is a think tank and a multistakeholder governance group which is focused on renewable energy policy. REN21's goal is to facilitate policy development, knowledge exchange, and joint a ...
'', published 2006, accessed 2007-05-16
Global growth is expected to be 2.8% annually until the mid-2020s when capacity will be about 150 gigawatts. China planned to electrify a further 10,000 villages between 2005 and 2010 under their
China Village Electrification Program The China Village Electrification Program (''Song Dian Dao Cun'') was a scheme to provide renewable electricity to 3.5 million households in 10,000 villages by 2010. This was to be followed by full rural electrification using renewable energy by 20 ...
, including further investments in small hydro and
photovoltaics Photovoltaics (PV) is the conversion of light into electricity using semiconducting materials that exhibit the photovoltaic effect, a phenomenon studied in physics, photochemistry, and electrochemistry. The photovoltaic effect is commercially us ...
. By 2010, China had 45,000 small hydro installations, especially in rural areas, producing 160 Twh annually. Over 50% of the world's potential small hydro power was found in Asia; however, the report noted, "It is possible in the future that more small hydropower potential might be identified both on the African and American continents". In the mountains and rain forests of British Columbia, Canada there are a great many sites suitable for hydro development. However environmental concerns towards large reservoirs after the 1980s halted new dam construction. The solution to coping with increased demand was to offer contracts to independent power producers, who have built 100 run of the river projects under 50 MW. Power production without reservoirs varies dramatically, but older conventional dams retain or release water to average out production though the year. In 2014 these independent producers generated 18,000 GWh from 4,500 MW of capacity.


Generation

Hydroelectric power is the generation of electric power from the movement of water. A hydroelectric facility requires a dependable flow of water and a reasonable height for the water to fall, called the head. In a typical installation, water is fed from a reservoir through a pipe into a
turbine A turbine ( or ) (from the Greek , ''tyrbē'', or Latin ''turbo'', meaning vortex) is a rotary mechanical device that extracts energy from a fluid flow and converts it into useful work. The work produced by a turbine can be used for generating e ...
. The water flowing through the turbine causes an electrical generator to rotate, converting the motion into electrical energy. Small hydro may be developed by constructing new facilities or through re-development of existing dams whose primary purpose is flood control, or irrigation. Old hydro sites may be re-developed, sometimes salvaging substantial investment in the installation such as penstock pipe and turbines, or just re-using the water rights associated with an abandoned site. Either of these cost saving advantages can make the return on investment for a small hydro site well worth the use of existing sites.


Project design

Many companies offer standardized turbine generator packages in the approximate size range of 200 kW to 10 MW. These "water to wire" packages simplify the planning and development of the site since one vendor looks after most of the equipment supply. Because non-recurring engineering costs are minimized and development cost is spread over multiple units, the cost of such package systems is reduced. While synchronous generators capable of isolated plant operation are often used, small hydro plants connected to an electrical grid system can use economical
induction generator An induction generator or ''asynchronous generator'' is a type of alternating current (AC) electrical generator that uses the principles of induction motors to produce electric power. Induction generators operate by mechanically turning their ro ...
s to further reduce installation cost and simplify control and operation. Small "run of the river" projects do not have a conventional dam with a reservoir, only a weir to form a headpond for diversion of inlet water to the turbine. Unused water simply flows over the weir and the headpond may only be capable of a single day's storage, not enough for dry summers or frozen winters when generation may come to a halt. A preferred scenario is to have the inlet in an existing lake. Modular “micro hydrokinetic” systems have been developed for
irrigation canals Irrigation (also referred to as watering) is the practice of applying controlled amounts of water to land to help grow crops, landscape plants, and lawns. Irrigation has been a key aspect of agriculture for over 5,000 years and has been develo ...
. "
Irrigation district In the United States an irrigation district is a cooperative, self-governing public corporation set up as a subdivision of the State government, with definite geographic boundaries, organized, and having taxing power to obtain and distribute water f ...
s across the U.S. have installed power plants at diversion points and in-canal drops, which are traditionally used for flow measurement, to stabilize upstream heads and to dissipate energy where there is significant elevation change throughout the canal system." Countries like India and China have policies in favor of small hydro, and the regulatory process allows for building dams and reservoirs. In North America and Europe the regulatory process is too long and expensive to consider having a dam and a reservoir for a small project. Small hydro projects usually have faster environmental and licensing procedures, and since the equipment is usually in serial production, standardized and simplified, and the civil works construction is also reduced, the projects may be developed very rapidly. The physically smaller size of equipment makes it easier to transport to remote areas without good road or rail access. One measure of decreased environmental impact with lakes and reservoirs depends on the balance between stream flow and power production. Reducing water diversions helps the river's ecosystem, but reduces the hydro system's return on Investment (ROI). The hydro system design must strike a balance to maintain both the health of the stream and the economics.


Sample list of small installations worldwide

Africa *
Zengamina Zengamina is a small hydroelectric power generation plant near Kalene Hill, Ikelenge District in northwestern Zambia. It was built between 2004 and 2008 at a cost of about $3 million, or $4,285 per kilowatt of power. Background Before the powe ...
, a 700 kW plant in
Kalene Hill Kalene Hill is a community in the northwest of Zambia near a hill by the same name about to the southeast. It is part of the Ikelenge District. Kalene Hill was the site of an early medical mission. The hospital is still important to the region. ...
, Mwinilunga District in northwestern Zambia. 2008 Asia *Meenvallam Small Hydroelectric Project, Palakkad district, Kerala, India. *Bario Asal & Arur Layun Micro-Hydro Community Project,
Kelabit Highlands The Kelabit Highlands are a mountain range located in the northernmost part of Sarawak, Malaysia in the Miri Division. It hosts the Bario village. The highest mountains in this range are Mount Murud at , Bukit Batu Buli at , and Bukit Batu Lawi a ...
,
Sarawak Sarawak (; ) is a state of Malaysia. The largest among the 13 states, with an area almost equal to that of Peninsular Malaysia, Sarawak is located in northwest Borneo Island, and is bordered by the Malaysian state of Sabah to the northeast, K ...
, Malaysia. 2009 *Ambangal Mini Hydro Electric Power Plant,
Kiangan Kiangan, officially the Municipality of Kiangan is a 4th class municipality in the province of Ifugao, Philippines. According to the 2020 census, it has a population of 17,691 people. Kiangan is the oldest town in the province. It derives its ...
,
Ifugao Ifugao, officially the Province of Ifugao ( ilo, Probinsia ti Ifugao; tl, Lalawigan ng Ifugao), is a landlocked province of the Philippines in the Cordillera Administrative Region in Luzon. Its capital is Lagawe and it borders Benguet to the ...
, Philippines (2010) *Asiga River Mini Hydro Electric Power Plant, Santiago,
Agusan del Norte Agusan del Norte, officially the Province of Agusan del Norte ( ceb, Amihanang Agusan; Butuanon: ''Probinsya hong Agusan del Norte''; tl, Hilagang Agusan), is a province in the Caraga region of the Philippines. Its capital is the city of Cabadb ...
, Philippines (2019) *Balongbong Mini Hydro Electric Power Plant, Bato,
Catanduanes Catanduanes (; ), officially the Province of Catanduanes, is an island province located in the Bicol Region of Luzon in the Philippines. It is the 12th-largest island in the Philippines, and lies to the east of Camarines Sur, across Maqueda C ...
, Philippines (1983) *Cantingas Mini Hydro Electric Power Plant, San Fernando, Romblon, Philippines (2009) *Likud Mini Hydro Electric Power Plant, Asipulo and Kiangan, Ifugao, Philippines (2015) *New Bataan Hydro Electric Power Plant, New Bataan, Davao de Oro, Philippines (2018) *San Luis Mini Hydro Electric Power Plant, San Luis,
Aurora An aurora (plural: auroras or aurorae), also commonly known as the polar lights, is a natural light display in Earth's sky, predominantly seen in high-latitude regions (around the Arctic and Antarctic). Auroras display dynamic patterns of bri ...
, Philippines (2011) *Villasiga Mini Hydro Electric Power Plant, Bugasong,
Antique An antique ( la, antiquus; 'old', 'ancient') is an item perceived as having value because of its aesthetic or historical significance, and often defined as at least 100 years old (or some other limit), although the term is often used loosely ...
, Philippines (2016) *Pakpattan Hydro Power Project, a 2.82 MW plant on Pakpattan Canal in
Pakpattan Pakpattan ( Punjabi and ), often referred to as Pākpattan Sharīf (; ''"Noble Pakpattan"''), is the capital city of the Pakpattan District, located in Punjab province of Pakistan. It is the 48th largest city of Pakistan by population according ...
District, Pakistan 2015 Europe *Green Valleys Project,
Brecon Beacons National Park The Brecon Beacons National Park ( cy, Parc Cenedlaethol Bannau Brycheiniog) is one of three national parks in Wales, and is centred on the Brecon Beacons range of hills in southern Wales. It includes the Black Mountain ( cy, Y Mynydd Du) i ...
, Wales. Joint winner of £300K in Big Green Challenge 2009. *St Catherine's, a National Trust site near
Windermere Windermere (sometimes tautologically called Windermere Lake to distinguish it from the nearby town of Windermere) is the largest natural lake in England. More than 11 miles (18 km) in length, and almost 1 mile (1.5 km) at its wides ...
, Westmorland, United Kingdom. North America *
Ames Hydroelectric Generating Plant The Ames Hydroelectric Generating Plant, constructed in 1890 near Ophir, Colorado, was one of the first (if not the first) commercial system to produce and transmit alternating current (AC) electricity for industrial use and one of the first AC h ...
,
Colorado Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of the ...
, United States. On the
List of IEEE Milestones The following timeline tables list the discoveries and inventions in the history of electrical and electronic engineering. History of discoveries timeline History of associated inventions timeline List of IEEE Milestones The following li ...
* Childs-Irving Hydroelectric Facilities, Arizona, United States. 1916 Now decommissioned *
Snoqualmie Falls Snoqualmie Falls is a waterfall in the northwest United States, located east of Seattle on the Snoqualmie River between Snoqualmie and Fall City, Washington. It is one of Washington's most popular scenic attractions and is known internationa ...
,
Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered o ...
, United States. 1957 * Malibu Hydro, British Columbia, Canada. 2005 *
Menihek Hydroelectric Generating Station The Menihek Hydroelectric Generating Station is a conventional hydroelectric generating station at Menihek Lake in Labrador. The dam and powerhouse are located in the Canadian province of Newfoundland and Labrador, south of the isolated town of ...
, Newfoundland and Labrador, Canada. 1954 * Cloudworks Energy is one of many Independent power producers that have built projects in British Columbia, Canada


See also

*
Electricity generation Electricity generation is the process of generating electric power from sources of primary energy. For utilities in the electric power industry, it is the stage prior to its delivery ( transmission, distribution, etc.) to end users or its stor ...
* Hydro power *
Low head hydro power Low-head hydropower refers to the development of hydroelectric power where the head is typically less than 20 metres, although precise definitions vary. Head is the vertical height measured between the hydro intake water level and the water level ...
*
Micro hydro Micro hydro is a type of hydroelectric power that typically produces from 5 kW to 100 kW of electricity using the natural flow of water. Installations below 5 kW are called pico hydro. These installations can provide power to an ...
up to 100 kW *
Pico hydro Pico hydro is a term used for hydroelectric power generation of under 5 kW. These generators have proven to be useful in small, remote communities that require only a small amount of electricity for example, to power one or two fluorescent ...
up to 5 kW * Conduit hydroelectricity *
International Center on Small Hydro Power International is an adjective (also used as a noun) meaning "between nations". International may also refer to: Music Albums * ''International'' (Kevin Michael album), 2011 * ''International'' (New Order album), 2002 * ''International'' (The T ...


References

{{DEFAULTSORT:Small Hydro Hydroelectricity Power station technology Renewable energy Distributed generation