TYPICAL PRELIMINARY DESIGN PROCEDURE FOR DAM BASED SCHEMES 

Click
to Go Back to Tamilnadu Projects
The Sathanur Dam is situated in Dharmapuri District on the River Ponnair. The average annual yield from the catchment of 10,826 square kilometers is 410 MCM which is released through five dam sluices of 1.52m width and 1.83m height. About 13 cumecs is discharged continuously from the sluices into two irrigation canals. Two of the existing five sluices would be utilized for the proposed mini hydro scheme. The original proposal by TNEB was to install 2 x 7.5MW and to produce 27.7 GWh/year. 

Flow Duration Curve: The revised proposal is based on daily discharge data at Sathanur over a 15 year period. From the flow Duration curve shown, it is apparent that multiple units could be installed to utilize 10 cumecs each; 10 cumecs would be available for the first unit for upto 73% duration; an additional 10 cumecs would also be available to the second unit for about 30% duration; and so on upto 70 cumecs for less than 10% duration.  
Head Duration Curve: The head was found to be 20 meters for 6070% duration, between 20 to 25 meters for 5060% duration, and 25 to 30 meters for 3550% duration. A design head of 27.5m, which corresponds to the 40% duration, was selected. Hence for this study, the design head is assumed to be 27.5 meters. Hence, by adopting a design discharge of 10 cumecs per unit, units of 2500kW would be feasible.  
Energy Curve: The energy curve produced based on the average flows and the design head , provides the following information on the incremental energy that could be recovered at the dam by increasing the design discharge level in steps of 10 cumecs. Assuming 80% efficiency of the turbinegenerator sets, the energy output and B/C rations from a multi unit configuration are given in the table. 
 


Copyright 2002
SECSD Private Limited 