RELIABILITY EVALUATION OF A GENERATION-RESOURCE PLAN USING CUSTOMER-OUTAGE COSTS IN INDIA

Customer-outage costs (COCs) are used to evaluate reliability of the g eneration-resource plan for a major power system in India, through dev elopment of an analytical reliability evaluation model, Extensive fiel d surveys were conducted of different customer categories to examine i nconveniences faced due to electricity interruptions. A composite outa ge cost function weighted across all customer categories in the region is estimated in a log-linear functional form. The inherent outage cha racteristics of existing and prospective generation resources under th e country's capacity expansion program, the National Power Plan, are i ntegrated with the COCs to obtain an interrupted energy value (IEV) wh ich is a customer value-based generation-reliability index. The IEV fo r the plan is found to be Rupees (Rs,) 2.30 per kWh of electrical ener gy not served in 1990, The COG-based reliability-planning criterion pr ovides an optimal level of reliability equivalent of 9.1% loss-of-load probability. Comparison of socially optimal reliability and expected implicit reliability level of the 1990-2000 generation-resource plan s hows that the expansion program is unreliable in the earlier years but becomes over-reliable towards the latter years of the planning horizo n. The study also illustrates that adaptive response investments which ameliorate the impact of interruptions in grid supply at a lower cost have substantially displaced potentially higher direct-outage costs. Copyright (C) 1996 Elsevier Science Ltd.