The Coalition is unable to say how much nuclear energy it plans to generate, its energy spokesperson says.
The amount of power is one of many details the opposition did not provide on Wednesday when it said it wanted to build seven nuclear plants across five states between 2035 and 2050. Other details include cost and precise timing.
But business and experts say the power generation figure is essential for energy investors to understand what balance of nuclear, renewables and gas the Coalition proposes for Australia, and plan their investments accordingly.
Energy spokesperson Ted O'Brien, who designed the plan, told the ABC's Insiders the amount of energy generated would depend on the type and number of reactors built at each site, and that neither of those things could be known until a Coalition government could establish a nuclear expert agency to undertake studies.
"We would be leaving that to the nuclear energy co-ordinating authority," he said.
"That independent body is to work out at each site what is the feasibility of certain technologies and only from there can you come down to a specific number of gigawatts."
That is unlikely to satisfy the concerns of industry groups who point to Labor's annually updated Integrated System Plan, which lays out its proposed energy mix in gigawatts.
Australian Industry Group chief Innes Willox said this was important for "certainty" and investor confidence.
But Mr O'Brien said gigawatts were "very specific" and the Coalition would instead offer its "assumptions" and provide a broad figure for "how much we believe there will be come 2050".
"I'm a Liberal and I appreciate and respect that investors want to make money, but to be really clear our focus is on the Australian people that want to save money," he said.
Mr O'Brien also revealed the Coalition planned to have multiple reactors on some sites, which would increase the amount of energy produced.
Estimates from experts have put the amount of power able to be generated by seven nuclear sites at about 10 gigawatts, or less than 4 per cent of Australia's energy needs.
Mixed signals on renewables
The proposed energy contribution of nuclear is also relevant to the status of the renewables rollout and the extent to which the Coalition would seek to continue it in government.
Nationals leader David Littleproud has consistently framed the nuclear policy as an alternative to renewables and even suggested there would be a renewables "cap".
But Mr O'Brien said on Sunday that was not the Coalition's policy and the Coalition was "united around the idea by 2050 of a net zero power grid".
Mr O'Brien added he did not believe renewable energy could be used as Australia's "baseload" power source, labelling the government's 85 per cent renewables target as unrealistic.
Asked what the Coalition would do about the looming short-term energy shortfall, given 90 per cent of coal power is set to exit the National Electricity Market within the next decade and before the first proposed nuclear plant would be built, Mr O'Brien said the answer was to "pour more gas into the market" but also said he would "welcome all renewables".
"The government believes the aim of the game is to maximise the amount of renewables. We want the optimum amount."
The government supports renewables through its Capacity Investment Scheme, which underwrites approved renewables projects to give investors a "revenue safety net". The Coalition's plans for that scheme in government are not clear, but Mr O'Brien promised renewable and gas projects would be forthcoming.
Environment Minister Tanya Plibersek said the Coalition's plan threatened the progress of renewables in the short-term.
"You're not going to see [a nuclear plant] for a decade at least. Australians want relief from their energy bills now," she told Sky News on Sunday.
"We're seeing renewables entering our energy market, bringing down the cost of energy. It's already happening, and instead Peter Dutton's got some plan he won't tell you the cost of that might help in a decade's time.
"We can be a renewable energy superpower and instead Peter Dutton wants to slam the breaks on, instead of us leading the world with renewable energy he wants to put us on the slow lane. It's just mad."
John Grimes, chief executive of the Smart Energy Council, said the Coalition policy was "a spoke in the wheel of progress" and was actively undermining renewables.
Mr Littleproud again on Sunday morning said the explicit intention of the nuclear policy was less renewables.
"That's just math," he told Sky News, saying there would be fewer transmission lines and less "tearing up [of] prime agricultural ground" under the Coalition.
While the Coalition has not yet revealed the cost, Mr Littleproud said the construction costs were "in the ballpark" of $8 billion per unit.
Asked about the higher cost of nuclear in most expert analysis, he said the government would "control" the plants and could run them in a way that would "drive down the cost".
Mr O'Brien also flagged a plan for "market reform" to reduce prices, but did not elaborate.
Two years of community consultation to 'make sure they understand'
Mr Littleproud and Mr O'Brien both flagged two and a half years of local community consultation would be needed before site details could be finalised, but that communities would not be given the opportunity to veto.
"That is not international best practice," Mr O'Brien said.
"We are taking this to the Australian people, we are seeking a mandate."
He added he did not expect that communities were likely to oppose the plants.
Mr Littleproud said he planned to "take the Australian people on a journey … [we would] start the two and a half year consultation process with those communities to make sure they understood".