Regulation of risk and vulnerability analysis in distribution networks - The Swedish experience

Modern society is highly dependent on continual electrical distribution. A storm hitting Sweden early in 2005 clearly indicated that the power distribution, like all technological systems, cannot be viewed as 100 percent reliable. After the government identified a need for systematic identification of potential causes of power outages and measures to mitigate them, the parliament issued a legal demand for local and regional network operators to perform risk and vulnerability assessment of their networks. From January 2011 the law also demands that no interrruption shall be longer than 24 hours. This paper deals with lessons learned by the Swedish regulator while preparing regulative directions for the content, reporting and publication of such assessments. The directions are supposed to be a guide and help the operators as well as act as a foundation for the regulator´s future monitoring an reviewing of the continuity of supply.