Introduction
The main functions of the power house are to support and house the generating units and their accessories as well as the water passages with the purpose of good performance of the plant, cost saving and easy inspection and maintenance.

Guidelines for Dimensioning of Power House

• The dimensions of the power house in plan are determined by the dimensions of generating equipment including governor.
• In the case of power houses with very low heads, the dimensions of the of the spiral case and draft tube govern the size of power house.
• The power house normally comprises unit bays, service bay and the control room. For a power house having 2 to 3 units, the width of the service is generally kept equal to one unit bay width.
• In case of a power house with very small capacity units, the unit can be planned to be overhauled outside the power house building and as such there can be no service bay at all.
• The center to center spacing of the unit bays is so determined that the clearance between the turbine-generator and the walls is enough for the erection and disassembly of the units. The passageway for operators must be considered.
• The determination of the center line of the runner i.e., setting of turbines is very important for the power house design. For reaction turbines, it is determined by the parameters of the turbine with respect to minimum tail water level. In case of Pelton turbine, it is set above the highest tail water level.
• The elevation of the entry into the power house is fixed considering the highest flood level in the tailrace.
• The height of the power house is fixed based on the clearances required to lift and carry the biggest size machine part throughout the power house.

General layout drawings preparation

• Firstly, the level of the center line of the runner should be fixed based on the water level of the tailrace.
• In case of a horizontal machine, there is normally one floor of the machine hall. In case of vertical machine, there may be two to three floors depending upon the requirement of auxiliary equipment.
• The level of the service bay is fixed above the high flood level.
• The service bay can be located either on the left or right side of the machine hall based on the location of the approach road as all the power house equipment is first unloaded and erected in the service bay.
• Normally gates are required to close the draft tube outlet openings for segregating the machines from downstream water at the time of erection and maintenance. These are operated from the draft tube deck. The level of this deck is kept above the maximum downstream water level.
• The control room can either be kept on the upstream or downstream side of the machine hall or in a separate building adjoining the power house.
• The main unit transformers can either be kept on the draft tube or at a location upstream of the power house or in the switchyard itself.
• Drainage and dewatering of sump are normally required to collect all the drainage of the power house & dewatering the draft tubes for maintenance. The sump can be located either at the end of the machine hall, or somewhere in the middle, in the erection bay or below the draft tube deck.

(Reference: AHEC-IITR, 2.2 and 2.3 Hydraulic and Structural Design)

3D Power House Layout
Layout drawings are essential information during the early development stages of a hydropower plant. They will define the positioning of all electromechanical equipment, as well as the accesses, circulation ways on the floors, assembly, and disassembly routes. Basically power house layout is the document that allows equipment suppliers, civil engineering, and Customer to decide on the best plant arrangement.

Taking this as fundamental, the concept of presenting this information in three dimensions for a better visualization has become standard in FLOVEL’s Design & Engineering. It was developed a parameterization to allow our designers to obtain the main block of the power house easily and quickly, also containing the equipment to be installed. All in accordance with all the guidelines and good design practices mentioned above.

The user interface is a library of parametric templates, one for each type and variant of turbines. With the entry of a few data, the 3D layout generation is automatic. Adjustments and customizations can be made manually in the parameterized model.

About FLOVEL:

FLOVEL name has been synonymous with the hydro power sector for over four decades. FLOVEL is a full-line supplier of electromechanical equipment and services for small and medium size hydro power plants manufacturer of hydraulic turbines, valves and turnkey supplier of electro mechanical packages for hydro power projects and ranks amongst the leading players globally. FLOVEL manufacturers complete range of Pelton, Francis, Kaplan, Axial Flow turbines and Valves for hydropower projects. The strength of FLOVEL is in its ability to offer all-inclusive solutions (Electro Mechanical-Turnkey Packages).