While other members of our team are currently offline due to the effects of major flooding in Brisbane, I was alerted to an AEMO Market Notice announcing a market suspension for the TAS region. The notice was published at 12:39pm AEST this afternoon.
MARKET NOTICE 094979
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Notice ID 94979
Notice Type ID Market suspended in region(s).
Notice Type Description MARKET
Issue Date Tuesday, 1 March 2022
External Reference Declaration of electricity market suspension
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AEMO ELECTRICITY MARKET NOTICE
Declaration of electricity market suspension
AEMO declares the spot market suspended in Tasmania with Market Suspension Schedule Pricing (refer NER clause 3.14.5(b)) from Trading Interval 1240 hrs on 1 March 2022 until further notice.
Dispatch prices for the first one or two dispatch intervals of this market suspension will be reviewed manually.
AEMO has determined that it has become impossible to operate the spot market in accordance with the provisions of the Rules due to Failure of SCADA systems.
Manager NEM Real Time Operation
The market suspension coincided with two undersea fibre cables being ‘accidentally severed’ which led to parts of the island state losing access to internet and mobile coverage. The ABC later reported that “the disruptions were caused by two separate cuts to two of the three cables connecting Tasmania to the mainland, occurring within two hours of each other”.
It appears the Basslink cable continues to be operational during this period.
As at Tuesday 5pm (AEST), the market suspension is yet to be lifted and the latest reports suggest that work is still being done to restore the two cables.
Market suspensions in the NEM are rare but this one comes less than two weeks after the market was briefly suspended in SA for unrelated reasons.
I find it interesting, from an electricity grid perspective, that the last man standing, the intact third connection was the Bass Link cable.
“Some traffic was re-routed over the Basslink cable, so Telstra’s mobile and some other services remained online, along with TasmaNet.” according to https://www.itnews.com.au/news/digital-tasmania-lobbies-gov-to-support-new-cable-builds-576790
How strange the grid market operator has to suspend service due to non grid based cables being taken out.