Reserve margin evaluation for generation system using probabilistic based method

Reserve margin is one of the generation system reliability indices which should be appropriately defined. Too high reserve margin causes over-investment in generation system whereas too low reserve margin may result in unacceptable generation risk. This paper proposes method to calculate the value of appropriate reserve margin based on probabilistic method using a reliability index, i.e. Loss of Load Expectation (LOLE). Three generic capacities, i.e. 250, 500, and 750 MW, are used and tested with a modified Thailand system to obtain a range of appropriate reserve margin.