On 13 February 2014, the Australian Energy Market Commission (AEMC) commenced consultation on a rule change request submitted by the AER proposing a requirement for generator ramp rates and dispatch inflexibility profiles to reflect the technical capabilities of generating plant.
Rule change proposal
We are proposing a rule change which would require generators to submit ramp rates (at all times) that reflect the maximum the generator is safely capable of achieving. Our rule change proposal would apply equally to scheduled and semi scheduled generators, scheduled network services and scheduled loads. As a related matter, the rule change proposal also seeks to ensure that when a fast start inflexibility profile (FSIP) is submitted, it is reflective of actual plant limitations at the time.
We consider the rule change proposal would address the most egregious cases of congestion related disorderly bidding and will improve the security of the NEM.
AER Cover letter to AEMC accompanying Ramp rate and FSIP rule change proposal - 21 August 2013
AER rule change proposal to AEMC - Ramp rate and FSIP - 21 August 2013
Consultation paper
On 20 March 2014 we made a submission to the AEMC’s consultation paper on the rule change request proposing a requirement for generator ramp rates and dispatch inflexibility profiles to reflect the technical capabilities of the generating plant. The AER, as proponents of the rule change request, considered that ramp rates and dispatch inflexibility profiles are, on occasion, used by generators to achieve commercial objectives which can be harmful both in terms of inefficient market outcomes, and on the ability for the AEMO to efficiently manage the security of the electricity system.
Stakeholder forum
On 5 May 2014, the AEMC held a stakeholder forum in Melbourne to facilitate discussion on the key issues in the rule change request. The AER presented at this forum.
AER presentation - AER rule change proposal - Ramp rates and dispatch inflexibility - 5 May 2014
Draft determination
On 28 August 2014, the AEMC made a draft determination to make a more preferable draft rule. Our 9 October submission to the draft determination showed that the AEMC’s preferred rule would have increased minimum available aggregate ramp rates in New South Wales, Victoria and Queensland. However, our analysis suggested that the preferred rule may have led to a reduction in minimum aggregate ramp rates under certain conditions in South Australia and Tasmania, and as such should be examined more closely.
Options paper
On 20 November 2014, the AEMC extended the period of time for publication of the final rule determination to 19 March 2015 in light of a number of complex issues raised in submissions to the draft rule determination, particularly its potential impact on large thermal generating units. On 18 December 2014, the AEMC published an options paper on two further options to address issues raised in submissions to the draft determination. Our submission supported Option 2 on the assumption that the AEMC chose to not adopt our original proposal.