THE HYDROELECTRIC LOW DROPOUT
Moulin, 15 th century converted into a central low fell to near Nancy Frouard
DEFINITION
A Hydroelectric bass drop is a power plant that uses a waterfall useful from 2 to 20 meters.Usually, this fall is equiped with Kaplan's turbines, ie turbines with propellers with guidelines and fixed or ajustable blades. Thes turbines are said to react.
COMPOSITION
- Central is usually made of :
- Dam
- channel water
- screen
- building production
- Channel leakage
HYDRAULIQUE OPERATION
The low drop centralme captures a large volume of water (3 to over 100 m3 per second) in a small drop The water is brought to the scales at a rate not exceeding 1 m / s. It is free of the floating body by means of a rake. A valve can cut the arrival of the water, it can be replaced by grooves in cofferdam. The water is then put in speed in a room of water, then guided by a distributor to fixed guidelines or guidance, it then passes through the Kaplan turbine with adjustable blades can control the flow of water. The residual kinetic energy of water is then recovered by means of a "vacuum cleaner" whose form is intended to slow the water to return to the river without any energy. The turbine rotates at a speed of 100 to 200 rpm. A speed multiplier can cause a power generator or an alternator. The controller measures the level or flow of the river and opens the turbine and the guidelines on optimum conserverle flow for the river downstream and produce the best performance. A wheel good setup makes it possible to recover 92% of the theoretical energy of the water.
THE PRESERVATION OF ENVIRONMENT
The central drop is usually low grid equipped with characteristics of the bars are defined in collaboration with the Higher Council of Fisheries.
A fish pass allows migratory species crossing the hydraulic works and sometimes goes downstream ensures the descent of juveniles.
The screen gets the floating bodies most of which are branches or trees, but also tire pallets and plastic objects. All these floating bodies are extracted from the river and taken to landfill.
Only some plants recover these wastes are designated by the prefecture. The noise of machinery is increasingly controlled and careful sélectrion organs of production and construction materials can remain below the limits of noise allowed.
The inclusion of buildings in their environment is studied particularly in the construction of new plants, photo montages make it possible to analyze the impact of each solution.