Energy Minister Josh Frydenberg has torpedoed a list of demands from Victoria that could have secured the state’s support for the Turnbull government’s energy policy.

State and territory energy ministers will meet with Mr Frydenberg in Sydney on Friday to discuss the design of the National Energy Guarantee.

Labor-held states have a lot of unanswered questions, while coalition states are urging them to get on board quick.

Victoria’s Energy Minister Lily D’Ambrosio has called for emissions reduction targets to be set every three instead of five years and for them to be set by regulations.

“Every time a future federal government may wish to change the emissions level, if they have to run the gauntlet of the federal Senate, that is no certainty at all,” she told reporters in Melbourne on Wednesday.

The state also wants a transparent register to ensure the guarantee works in the best interests of consumers.

But while Mr Frydenberg said on Wednesday he was happy to keep talking to Victoria about the “11th hour demands”, he knocked each of them on the head.

The government isn’t going down a path of regulation over legislation for the renewable target, he said, pointing out Victoria had done the same with its renewable targets to provide investment certainty and commitment.

As for a registry, he said the Energy Security Board was already making public all information not considered commercially in confidence.

Earlier federal Labor leader Bill Shorten said he hadn’t given up hope an agreement could be struck.

“I think what we need to see is a fair dinkum negotiation on Friday. What I don’t want to hear is that Mr Turnbull says one thing to the states on Friday and another thing to his party room next Tuesday,” Mr Shorten said.

“I’m worried that Mr Turnbull doesn’t control his own party, cannot convince people there that lower energy prices from more renewable energy is the way to go.”

Mr Turnbull has assured coalition colleagues of his support for the underwriting of new dispatchable power generation.

“That’s a very good suggestion and I have no doubt that we will adopt that,” he told reporters in Alice Springs.

“It will need to be a lot of design in it.”

That policy, like the energy guarantee, would be technology agnostic, not favouring either renewables or fossil fuels.

Critics of the NEG in coalition ranks have stressed such a commitment is crucial, seeing it as a potential means of supporting new coal-fired power stations.

Liberal backbencher Craig Kelly, who has been outspoken in seeking changes, wouldn’t comment when asked if he’d cross the floor against the policy.

The ACT and Queensland have concerns about the lack of emissions reduction ambition needed to drive investment in renewables.

The Tasmanian and South Australian Liberal governments support the energy guarantee, warning delays will mean high power prices while NSW agrees it would give stability to the energy industry.