About 5.15am Tuesday fire and gas detection equipment on the Maui A platform automatically triggered an emergency shutdown of gas supplies, forcing several big users to either partially or completely close production facilities until Maui gas supplies were restored about 11.20am.
Methanex had to completely close its Taranaki methanol plant, Genesis Power switched its 1000MW Huntly station to coal, while Contact Energy shut its Otahuhu, Auckland, stations, although it managed to keep the New Plymouth station idling. NGC wound back electricity production at the Stratford TCC plant, which uses Maui and Tawn (Tariki, Ahuroa, Waihapa and Ngaere) gas.
Spot prices on the electricity market more than doubled, soaring to as much as $NZ525 per megawatt hour.
The Major Electricity Users Group (MEUG) said it would be asking questions about how Maui operator Shell Todd Oil Services was working to ensure further unplanned outages did not happen. "I think an explanation is needed of the Maui operator and I would be interested to know whether the government will seek a remedy in terms of its contract to purchase Maui gas," said MEUG executive director Ralph Matthes in Wellington.
"The field owner needs to take steps to urgently remedy this situation to ensure we don't have a fourth outage and, even if these shutdowns were just unfortunate coincidences, they need to deal with the perception in the industry that the Maui A platform and associated facilities are now becoming unreliable," said one commentator today.
Yesterday Simon King, spokesman for field owner Maui Development Ltd, said work was under way to isolate the cause of the false alarms, which he described as "unfortunate coincidences". Gas supply had been cut for six hours last Wednesday, two hours the following day and another six yesterday.
The A platform normally had power generation facilities in reserve, but these were still under repair after having been damaged as a result of damage suffered during last week's shutdowns.
Yesterday a back-up team was flown to the platform to help repair the damaged turbines and generation systems. Representatives of the turbines' manufacturers also traveled to the platform.
Meanwhile, just days after independent expert Netherland Sewell and Associates International reported that there was only 370PJ of economically recoverable gas left in Maui, Genesis Power is hiking gas prices for its residential customers.
All its North Island customers will be hit with the increases, believed to up to 15%, effective from March 20.
Chief executive Murray Jackson said Genesis had endeavored to keep prices as low as possible for as long as possible, and outlined reasons for the increases for its 95,000 customers, but did not give details of the price hikes.
