On 8/1/2024 the CAISO implemented the functionality defined in tariff section 11.17.2.1 whereby resources with deviations outside a tolerance band during the advisory shutdown horizon are disqualified from receiving minimum load costs (MLC). Since implementation, the CAISO received settlement disputes involving resources that were dispatched at Pmin when they had received an advisory shutdown and had their MLC disqualified even without any deviations outside the tolerance band. The CAISO has determined this outcome is inconsistent with the policy underlying tariff section 11.17.2.1 and is not a necessary outcome from that tariff section.
The CAISO is addressing this issue through a configuration change whereby the value of the shut-down state variable is null until an interval within the advisory horizon has deviations outside of the tolerance band. The result is that resources will not be disqualified from MLC under this rule until there is a deviation that exceeds the tolerance band.
The configuration change can potentially impact successor charge codes CC 6630, CC 6620, CC 66200, CC 6636, CC 6637, CC 6678, and CC 66780 with respect to qualification or disqualification of MLC for the IFM, RUC, or RTM, and allocation of bid cost recovery.
The configuration change will be deployed around 1/8/2025 and settle charge codes retroactive to Trade Date 8/1/2024 for the next run cycles. This change should resolve all the valid disputes and prevent similar disputes in the future.