Construction of representative networks considering investment scenarios based reference network concept

Distribution systems are inherent monopolies and therefore these have generally been regulated in order to protect customers and to ensure cost-effective operation. In the UK this is one of the functions of OFGEM (office of gas and electricity markets). Initially the regulation was based on the value of assets but there is a trend nowadays towards performance-based regulation. In order to achieve this, a methodology is needed that enables the reliability performance associated with alternative investment strategies to be compared with the investment cost of these strategies. At present there is no accepted approach for such assessments. Building on the concept of reference networks proposed in [G. Strbac et al. (2001), V. Levi et al. (2004)] this paper describes how these networks can be used to assess the impact that performance driven investment strategies will have on the improvement in reliability indices. The method has been tested using the underground and overhead part of a real system.