Basslink has made progress with repairs to the broken underwater power cable, and is preparing to cut it.

The company expects the cable will be operational by the end of May.

But Mr Groom said the government was planning for the worst in case the cable wasn’t back up and running for winter.

‘‘The government can’t control the rain, the government can’t control the timing of Basslink,’’ he said.

‘‘What we can control is contingencies.’’

Part of the plan includes the establishment of a high powered taskforce to look back at key decisions made in the lead up to the energy crisis, and make plans for the future.

Aurora Energy chairman Geoff Willis will step aside from his position to head the taskforce.

Mr Groom said an assessment would be made to determine whether gas generation was a more cost effective supply of energy, rather than diesel generation.

‘‘But we’ve got to go through a cost-benefit analysis and undertake planning in order to make those judgements,’’ Mr Groom said.

The state has 200 megawatts of diesel generators at its disposal, but their installation has cost $44 million and running just half of them will cost $11 million a month.

Mr Groom said power savings measures had been discussed with government agencies, but Tasmanians would not be forced to reduce power use.

Basslink chief executive Malcolm Eccles said the exact cause of the cable’s fault would not be known for some time and would require a detailed analysis of the damaged cable point before any conclusions would be reached.

‘‘In total, the repair teams have dedicated more than 30 days of round-the-clock fault location identification work due to the unexpected complexity of the fault,’’ Mr Eccles said.

‘‘While there remains some more days of work and analysis to be done before we can provide a more accurate estimate of return to service, it is an important milestone.’’

Opposition Leader Bryan Green said the energy crisis would ‘‘inevitably worsen over the coming months’’.

‘‘Every week that Basslink is offline, Matthew Groom’s mistakes will cost Tasmanians millions of dollars,’’ he said.

Greens environment spokeswoman Rosalie Woodruff said Mr Groom’s response had been ‘‘reactive and doggedly resistant to exploring energy reduction and renewable generation solutions’’.

Dam levels are down to 15.5 per cent, and before Basslink broke down in December Tasmania was importing 40 per cent of it power from interstate.