The Australian Energy Market Commission (AEMC) today released a draft determination to enhance emergency frequency control schemes in the national electricity market.
Emergency frequency control schemes are ‘last line of defence’ mechanisms, such as controlled load shedding, which are designed to protect against a major blackout if a sudden, unexpected loss of generation or load causes rapid changes in system frequency.
The draft rule would allow for the use of the most efficient solutions, incorporating current and any future technologies, so that emergency frequency control schemes remain capable of limiting the consequences of emergency events. The proposed changes also include new formal arrangements to control sudden increases in frequency, known as over-frequency events.
The draft rule also introduces a new ‘protected event’ category. For a protected event, the Australian Energy Market Operator (AEMO) would be able to take some pre-emptive actions, such as purchasing frequency control ancillary services or constraining the system, as well as some load shedding, to limit the consequences of the protected event for energy consumers.
While enhanced emergency frequency control schemes and the new protected event category would help support security of the power system, they may also result in additional costs, which are ultimately borne by consumers. For example, network businesses and generators may need to purchase new equipment to deliver emergency frequency control schemes and AEMO may need to procure additional frequency control services for a protected event.
The draft rule therefore requires the Reliability Panel to undertake a cost benefit assessment when setting the standard for each emergency frequency control scheme, and when determining how AEMO will manage the system for a protected event. This is consistent with the Reliability Panel’s role in the System Restart Standard and the Frequency Operating Standards.
These rule change requests, which were submitted by the South Australian government, follow analysis undertaken by AEMO’s Power System Implications Technical Advisory Group in 2015, which identified a range of emerging technical challenges as the national electricity market transitions to a lower emissions future. The proposed rule changes address concerns about emergency protection, particularly in relation to South Australia’s current frequency issues, as the power system transitions away from conventional, synchronous generation - such as coal, gas and hydro - towards new non-synchronous technologies such as wind farms and solar panels.
The AEMC is considering these rule changes in coordination with our wider system security review.
Submissions on the draft determination are due by 16 February 2016.
The Reliability Panel
The Reliability Panel's core functions relate to the safety, security and reliability of the national electricity system. The focus of the Panel's work is on determining standards and guidelines which are part of the framework for maintaining a secure and reliable power system. The panel is chaired by AEMC Commissioner, Mr Neville Henderson. Its members are broadly representative of all stakeholders interested in the operation of the power system and the electricity market including consumer groups, generators, network service providers, retailers and the power system and market operator, AEMO