Storage levels increased by 0.2 per cent despite the maximisation of Hydro generation in the Pieman, Mersey-Forth and Derwent schemes and the dialling back of diesel and gas generation to prevent storages from spilling. 

All diesel generation was switched off as of Monday afternoon, with Hydro Tasmania set to closely monitor rainfall and inflows to determine when and how much diesel would be turned back on. 

Hydro expects further rainfall over catchment areas this week.

Energy Minister Matthew Groom said storage levels at key energy generation sources, Great Lake and Lake Gordon, had increased by 0.3 per cent each.

Mr Groom said the Tamar Valley Power Station’s Rolls Royce Trent Unit was shut down on Saturday after an exhaust gas leak was identified.

He said the fault was set to be fixed by the end of the week and was unrelated to a previous issue that saw the unit sent to Abu Dhabi for repair last September.

It’s the second time the unit has been shut down since it returned to early service last month.

Three 25 megawatt dual fuel units at the decommissioned Bell Bay Power Station are set to be online in about two weeks, the same time Hydro expects 220 megawatts of additional generation to be operational.

Opposition Leader Bryan Green said the state needed at least a month of solid rain to see a significant improvement in storage levels.

“The modest increase of .2 per cent shows how much rain is required to get our dams back to safe operating levels,” Mr Green said.

“While the major industrials are still power rationing, we’re not out of the woods.”

Mr Green said the Basslink cable needed to be fixed by its mid-June target date to help dams recover.

Basslink is expected to start the next phase of its cable repair job this week, subject to favourable weather conditions.

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