Emerging reliability requirements for distribution systems in extreme weather conditions

Extreme weather conditions challenge electricity distribution from time to time. In the Nordic countries, strong wind and snow storms together with the high rate of overhead lines located in forests create demanding conditions for the distribution business. To meet the requirements of modern society, management of major blackouts plays a significant role in the economic regulation of the electricity distribution business. This paper presents the results of a survey commissioned by the Finnish Ministry of Employment and the Economy on supply interruptions and electricity supply security. The paper focuses on two main elements; the customer compensation payments and the maximum blackout duration limits. The study is based on actual largescale blackouts experienced by several distribution companies.