Run-of-the-river hydroelectricity

A hydroelectric power plant is a hydroelectric power plant, in which the flow above the weir and the associated outflow are always just below the power plant during normal operation, so is no storing up water for economical use in consumption and inflow fluctuations. Other names are run-of- river or power plant.

• 4.1 Current production
• 4.2 Marine

History

In 1767, the English civil engineer John Smeaton, the first water wheel made ​​of cast iron forth. 1853 electric power was generated at Niagara Falls, and in 1896 came here the first major power plant in the world. 1880 we built the first hydroelectric plant in northern England. 1886 originated in Switzerland, the power plant Thornberg which was already producing alternating current.

In Austria, under the inventor Frederick William Schindler was born in 1884 a small hydroelectric power plant, from which later developed the Vorarlberg power plants. A year earlier, allegedly caused a small power plant in New York.

The International Electrotechnical Exhibition which was held from 16 May to 19 October 1891, a breakthrough for the first three-phase transmission, the generating hydroelectric power plant was in Lauffen.

The Elektricitäts works Reichenhall were Germany's first hydroelectric power plant and were taken on 15 May 1890 in Bad Reichenhall in operation. It was also the first AC power plant ( " Public Lighting " ) in Germany and the first power station in Bavaria. As an fell dry for Saalachstrasse power plant numerous Mühlbäche in the city by the construction of the dam in 1912, the old power plant was abandoned and demolished in the sequence. As a replacement also supply power to the city was delivered from the Saalachstrasse power plant. This explains why today both railway power at 16.7 Hz and 50 Hz AC power is generated in Saalachstrasse power plant.

Bavaria's second oldest hydropower plant in Schöngeising has been in operation since the year 1892. It was built according to the plans of Oskar von Miller, the son of Ferdinand von Miller in two years time. It was built on the site of a mill offered for sale at the Amper. With the power of two initially Knop turbines the nearby county town Fürstenfeldbruck was supplied as one of the first resorts in Bavaria for street lighting. With now three Francis turbines from the years 1911/22/27 and two generators (1922 /27), the power plant of Stadtwerke Fürstenfeldbruck supplies for over 120 years in continuous operation power for the county. The average annual standard capacity is 2000 MWh. The historic Amper power plant is a listed building and can be visited on a guided tour.

The river plant Stallegg is the Wutachschlucht below Göschweiler and can be reached through the gorge trail. It was commissioned in 1895. It is still in front of the now broken Rheinfelden power plant is the third oldest river power plant in Germany and is a listed building.

In Switzerland, there were already 1895 88 power stations. A 1895 planned water and power plant, which Girard turbines were powered by a side channel of the Wutach, went live in January 1896 in Wunderklingen in operation. It was in 1968 replaced by a modern plant, which has been in operation since 1971.

Operation

The flow of water is passed through a water turbine, which converts the potential energy of water in a mechanical rotation. This rotary motion drives a generator. To increase the slope height, the river water is dammed by a weir. The water level in the resulting backwater area is maintained constant during operation. The drop height as the height difference between the upper water and underwater, as well as the design flow determine the installed capacity and the working capacity of the power plant. A diffuser at the outlet of the water turbine increases the efficiency at a given height difference, but also strengthened due to its vacuum form the risk of turbine damage due to cavitation.

Through a dam water is retained in the reservoir at the highest possible level of potential. The energy of the motion of the effluent water is transferred to a water turbine or a water, whereby the latter is caused to rotate with high torque. This in turn will be forwarded directly or through a gearbox to the shaft of the generator. The generator converts the mechanical energy into electricity. For the generator drive, Kaplan and Francis turbines are usually used. Other components are dependent on size and design of the power station.

Types

Since the fall height is usually low, it is the type of low-pressure power plant. Their performance is mainly achieved by high flow rates. Saving and hence the control of flow and power production is possible only in special cases.

Threshold operation

In run-of- threshold operation with the water is collected over a few hours in the storage space and the turbines only at certain hours. Therefore the turbine can be driven in the optimum efficiency. Furthermore, there is thus the possibility to generate power mainly when it is needed. Since the threshold operation underwater drops dry during Anstauphase and thus considerable ecological problems can cause, it is now approvable only with a balancing reservoir situated below.

Ausleitungskraftwerke

In a Ausleitungsanlage the pent up by the weir water via a channel or tunnel is routed to the power house, which is not directly at the weir. Thus, the river is usually greatly reduced, and thus to gain height of fall. So the Innschleife is cut off at Landeck and thus achieved a total drop of 143.5 m at Innkraftwerk bei Imst by a 12.3 km long headrace tunnel.

Drinking water plant

A special feature is the water line power plant in Gaming Gaming ( Lower Austria ) Represents the water of the Second Vienna Mountain Spring Pipeline overcomes between Lunz am See and gaming a gradient of 220 m. About a 600 m long pipe, the water is used to generate electricity and then sets on his way to Vienna.

This type is also called expansion turbine, their use is frequently done in the drinking water system. Here, the pressure difference is used in the piping system between elevated tank and distribution system. The use of pressure regulators may be dispensed with and a part of the pump of the water required in the high energy reservoir can be recovered.

Bay Power Plant

Very often we find the so-called Bay power plant, where it is a special type of block design. In this case, the power plant is located in an artificial bay on the natural course of the river. It makes sense to the arrangement of the bedload -free outside of a river bend his. Advantage of this design is that the flow cross-section is not narrowed and may flow off any possible floods safely.

Waterwheel

Water wheels are the oldest form of hydroelectric power plants. With small heads and low amounts of water because they have efficiencies that are comparable to those of turbines, they are still used today. Water wheels can run without significant adverse effects on the efficiency without control and with strongly fluctuating water levels. Therefore, they can have a higher annual working as turbines under certain conditions.

Water vortex power plant

The smallest form of a small hydropower plant is currently the water vortex power plant. In this type of flowing water is diverted by means of a short concrete ramp water and fed to a circular concrete tank with drain. The resulting water vortex drives a specially shaped vortex rotor generated by the resulting torque current.

Laufwasserkraftwerk without threshold operation

Power Buoy

A power - buoy is simply hung in the river and not changed the landscape. Such a buoy can also be used in sections of the river, where conventional hydroelectric power stations can not be built.

Hydrodynamic screw

Hydrodynamic screws come out with small amounts of water and small differences in altitude, are also used at high gradient. The amount of water can vary greatly.

Shaft power plant

Schacht power plants are suitable for very small drop heights. It is through the simple technique for decentralized systems in developing countries. The route will be DIVE turbine. The TU Munich optimizes this building type in their experimental station in Obernach.

Economics

Electricity production

Hydroelectric power plants generate electricity around the clock and the base load current are therefore used to cover. High tide and low tide degrades performance. At high tide will reduce the height of fall, because the water level rises below the weir. At low tide, the flow rate decreased. In winter, the electricity production due to the lower water levels in the rivers, less than in the summer. Due to the mostly good utilization of turbines ( > 50%) and at the same low cost of producing power plants running cost electricity. In Germany hydroelectric power plants and storage power plants with an installed capacity of 4215 MW ( 6% ) are available that provide a current production of 18.6 TWh in 4430 hours.

Shipping

In order to make despite the interruption of the watercourse through the weir the river navigable, locks to be built.

Due to the storage space navigation is often easier at low tide or made possible by the increase in water depth at all.

By stringing together of power plants on the Danube and the construction of the Main -Danube Canal an all-season waterway between the North and Black Sea was created for the inland waterways.

Ecology

Hydroelectric power plants generate electricity from renewable energy. Often caused by construction and operation of massive interventions in the environment that can lead to sustainable change in the ecology. It is expected consequences such as the loss of natural river dynamics, reducing the gravel transport, the loss of ecologically important flooding, a resulting reduction of nutrient entry into adjacent floodplains etc..

A special form of hydroelectric power plant is the current buoy. The effects on the environment are low compared to conventional hydropower plants.