CIVIL WORKS GUIDELINES FOR MICRO-HYDROPOWER IN NEPAL
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8. Powerhouse and tailrace
8.1 Overview
The powerhouse accommodates electro-mechanical
equipment such as the turbine, generator, agro-processing
units and control panels. The main function of this building
is to protect the electro-mechanical equipment from adverse
weather as well as possible mishandling by unauthorised
persons. The powerhouse should have adequate space such
that all equipment can fit in and be accessed without difficulty.
Cost can be brought down if the construction is similar to
other houses in the community. The powerhouse of the Barpak
micro-hydro scheme cun be seen in Photograph 8.1. This
building is similar to other local houses in the community.
Note that the transformer is fenced to prevent accidents due
to unauthorised access. The generators, turbines and the belt
drives need to be securely fixed on the machine foundation
in the powerhouse. This requires a careful design since the
equipment generates dynamic forces and even a slight
displacement can cause excessive stresses on various parts of
the equipment and lead to equipment malfunction. The
tailrace is a channel or a pipe that conveys water from the
turbine (after power generation) back into the stream; generally
the same stream from which the water was initially
withdrawn. The powerhouse and tailrace of the Salleri Chialsa
mini-hydro scheme can be seen in Photograph 8.2
Photo 8.1 Powerhouse of the Barpak mini- hydro scheme