Tower replacement on the Heywood to Alcoa Portland 500kV line - Regulatory Investment Test for Transmission

In accordance with the Rules and the AER RIT-T guidelines, the purpose of this PADR is to set out the detailed cost- benefit analysis of the credible options for addressing the identified need. [...] As a general principle, it is important that the methodology takes account of the identified need and the factors that are likely to influence the choice of the preferred option. [...] In relation to non-supply risks, our approach monetises this risk by multiplying the following parameter estimates: the probability of asset failure; the cost of consequence of the asset failure; the likelihood of the consequence given the failure has occurred; and the number of assets to which the analysis relates. [...] NSPs should explain the rationale for the selection of the key input assumptions and the variations applied to the analysis. [...] Cost benefit analysis The economic analysis allows comparison of the economic costs and benefits of each option to rank the options and to determine the optimal timing of the preferred option.