Reservoir Operation Optimization for Dzuza Multipurpose Project in Nagaland Using Chance Constraint Linear Programming

Abstract

 In this paper a Chance Constraint Linear Programming (CCLP) was formulated for reservoir operation of Dzuza multipurpose project in Nagaland.  The model can be used to determine the maximum annual hydropower that can be produced at different levels of reliability of meeting the irrigation demands. The irrigation requirement is taken as the priority which needs to be satisfied first. The release policy is defined by a chance constraint that the probability of meeting the irrigation release equaling or exceeding the irrigation demand, is not less than the specified value P. The CCLP model was run in LINGO 19.0 x 86 Version for various reliability levels of 60%, 65%, 70 % and 75% for meeting the irrigation demands with the objective of maximizing the annual hydropower generation.  The model results gave global optimum solution for the down- stream release for the bed turbine, reservoir water elevation, hydropower produced by the bed turbine, end-of-period storage for each month and the monthly spill from the reservoir for all reliability levels and shows that as the reliability level of meeting the irrigation demand increases the annual hydropower generation decreases and as the reliability level of meeting the irrigation demand decreases, the annual hydropower production increases. For 75% reliability of meeting the irrigation demand, the maximum annual hydropower produced is 26.99969 M kWh. Beyond 75%, the solution was found to be infeasible. The optimal end-of-period storages (rule curve) for reservoir operation of Dzuza multipurpose project was also determined using the CCLP model. The graphs for Bed power release vs. Energy produced illustrated how hydropower produced increases with the quantity of bed power release.