AEMO updates generator combinations for SA system strength

A brief note to note that NEM-watch has alerted to the fact that AEMO has published a Market Notice “Updated generator combinations for SA System strength” today (Friday 8th December):

For future reference, here’s the full text of the market notice.

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MARKET NOTICE
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From :              AEMO
To   :              NEMITWEB1
Creation Date :     08/12/2017     12:18:10

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Notice ID               :         60252
Notice Type ID          :         CONSTRAINTS
Notice Type Description :         New/Modified Constraints
Issue Date              :         08/12/2017
External Reference      :         Updated generator combinations for SA system strength

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Reason :

AEMO MARKET NOTICE

Updated generator combinations for SA system strength

AEMO is continuing to investigate system strength requirements in South Australia.

Through this work, AEMO has identified three additional generator combinations which meet minimum system strength requirements in South Australia.

These new combinations are:
LOW_11 – 1 x Torrens Island A units + all Pelican Point units
LOW_12 – 3 x Torrens Island A units + 1 x Torrens Island B units + 1 x Pelican Point GT/ST units
LOW_13 – 1 x Torrens Island A units + 3 x Torrens Island B units + Osborne GT/ST

The limit on non-synchronous generation in South Australia when only a minimum strength requirement is met has also now been increased from 1200 to 1295 MW for the new and existing combinations. The limit for higher levels of synchronous generation has also been increased from 1700 to 1870 – Heywood (Vic to SA) transfers.

For more information refer to the updated limits advice:
http://www.aemo.com.au/-/media/Files/Electricity/NEM/Security_and_Reliability/Congestion-Information/2017/Transfer-Limit-Advice—South-Australian-System-Strength.pdf

The advice also includes a guide as to which generator combinations are required to satisfy N-1 operational conditions.

The ID of the constraint equation which manages this limit has now changed from S_WIND_1200_AUTO to S_NIL_STRENGTH_1 and S_NIL_STRENGTH_2.

AEMO are continuing to investigate system strength requirements in South Australia. A further update to this advice is expected by late January 2018.

Ben Blake
AEMO Operations

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END OF REPORT
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We’ll watch these two new constraint equations in ez2view with keen interest – and, given the prior analysis we did on how much energy had been curtailed as a result, will be keen to update the calculation in early 2018.