Invitation to comment on Credible Event Review reports (Closed)

We have completed our final 2024 Credible Event Reviews as signalled in the 2024 Credible Event Review Scope and invite feedback from the electricity industry on our recommendations.

The reports are:

•  The Interconnecting Transformer (ICT) Methodology and Updates which proposes a simpler approach for categorising ICT events which will improve real-time monitoring of risks. This report does not change the risk mitigation methods applicable to ICTs. The report recommends that all ICTs should be classified as either Contingent Events (CE) or Extended Contingent Events (ECE), removing ‘Other’ as an available classification. This change simplifies the management of ICT risks in real-time by ensuring these ICTs are monitored within the operational timeframe.  This report also reviews the categorisation of ICTs at Bombay, Hamilton and Islington, and Kikiwa given recent grid upgrades or changes.
• The Approach to Fault Ride-Through (FRT) non-compliance. For most participants, there will be no impact from this report.  Asset owners who are unable to comply with their FRT requirements may request dispensations, and for those participants we propose to clarify how we will consider risk management options while assessing FRT dispensation requests.
• The 110 kV busbar fault review which concludes that we are seeing a slight increase in fault rates for these assets but that this increase does not warrant changes to 110 kV busbar classifications.

Submissions

We received one submission on Fault Ride-Through (FRT) non-compliance, which you can read below. 

Response to Submissions