A methodology for ranking locations according to the likelihood and consequence of extreme events

The present paper describes a methodology for evaluating major system risk on distribution networks, developed for and used by a distribution network operator (DNO) located in the North of England. Its purpose is to assess and rank each primary load point across the network as regards both the probability of extreme events occurring, and their consequence, expressed as a single major system risk index (MSR). This methodology was applied to around 150 separate load points, and the 40 with the highest MSR were further investigated to identify a range of possible mitigation strategies in each case. The paper concludes by evaluating the benefits of such a methodology to support long term network planning across a whole DNO, and by suggesting ways in which its applicability could be extended.