Variation of Cost of Unserved Energy depending on Interruption Duration: A Case Study for Sri Lanka

Abstract

The total cost arising due to an electricity outage for a unit of energy is known as the Cost of Unserved Energy. In other words, financial cost that consumers should have to invest to manage the effect of an electricity interruption is defined as the consumer interruption cost or Cost of Unserved Energy. Out of several methods available, consumer survey has become the outstanding and preferred method for estimating this cost; Electricity consumers were grouped into two categories as Industrial and Commercial for conduct of the survey. The values obtained for Cost of Unserved Energy are further analyzed to establish the variation patterns of Cost of Unserved Energy versus the interruption duration. The analysis shows a similar variation pattern for of Cost of Unserved Energy depending on interruption duration for each sub category in the Industrial and Commercial categories both. The values of these variation contain the summation of shutdown, loss of production and startup cost of each individual customer. Thus it is concluded that Cost of Unserved Energy variation versus interruption duration has a similar pattern with different magnitudes.