Rule Change: Open
This proposed rule change from AEMO seeks to improve the transparency and consistency of information AEMO provides to signal whether or not electricity supply is projected to meet demand in the medium-term.
On 12 April 2018 the Australian Energy Market Commission (AEMC) published a consultation paper for the Reporting of aggregate generation capacity for MT PASA rule change request.
The medium-term projected assessment of system adequacy, or MT PASA, assesses the adequacy of expected electricity supply to meet demand across a two-year horizon. This is done through regular assessment of any projected failure to meet the reliability standard.
Until now, the MT PASA has been formulated using static figures to determine whether the reliability standard is projected to be met – this can be considered a deterministic approach.
In 2016, AEMO commenced a redevelopment process to assess whether this MT PASA methodology was fit for purpose in Australia’s evolving energy market. As a result of the redevelopment process, a new MT PASA system is currently being adopted.
This new process probabilistically assesses the risk and uncertainties of power system operation, running 1,600 Monte-Carlo simulations to reflect the operation of the national electricty market. It will probabilistically determine whether the reliability standard is projected to be met.
Under the National Electricity Rules (NER), AEMO is required to report on aggregate capacity of generation in a region after allowing for the impact of network constraints as part of the MT PASA.
This requirement was drafted at a time when MT PASA was deterministic. However, assessment of the impact of network constraints is incompatible with the probabilistic modelling approach that is now being adopted in the redeveloped MT PASA.
The consultation paper seeks stakeholder input on AEMO’s proposed changes to the NER that would remove the requirement to consider network constraints when publishing aggregate capacity for each region in the MT PASA.
Submissions to the rule change request are due by 10 May 2018.
As this rule change request is considered non-controversial, the AEMC intends to assess the proposed rule under the expedited rule making process unless we receive a written request and substantive reasons not to do so from any person by 26 April 2018.
Under an expedited rule making process, a final rule determination must be made within six weeks of the initiation of the process.
As a result, the key dates for stakeholders in this process are:
• Commencement of this rule change process: 12 April 2018
• Submissions to the consultation paper to be received by (4 weeks): 10 May 2018
• Publication of final determination: 24 May 2018