Issues in integration of risk of cascading outages into utility reliability standards

This paper points to some ways in which concepts of `security' might be revised in order to more cost-effectively accommodate new generation and wider market interactions without undue increase in system unreliability. The background to `security standards' and the scope for change are discussed. A number of issues are cited that are likely to make the achievement of a theoretical ideal very difficult. It is concluded that, while new tools for estimating quantified risk should be very useful, the choices that must currently be made in modelling the power system and difficulties with obtaining good data mean that experience is required for their use and they do not negate the need for agreed `standards'.