Australia's climate wars are heating up again, with the nation's future energy mix looking potentially radioactive.
While federal Opposition Leader Peter Dutton insists nuclear power is the best way to achieve net zero by 2050, his position has not received strong support from senior state Coalition MPs, particularly in New South Wales, Victoria and Queensland.
Earlier this year, Victorian Liberal leader John Pesutto told ABC Radio Melbourne that he did not support the construction of nuclear reactors in the La Trobe Valley, the site of existing coal-fired power stations.
Queensland's Liberal-National leader David Crisafulli said nuclear was not on his agenda "because it just won't happen until Canberra sorts that out".
Some of the most vocal opposition has come from New South Wales' former Liberal treasurer Matt Kean, who dismissed nuclear as "hugely expensive" and a "Trojan horse" for the coal industry.
In addition, the nation's leading scientific body, the CSIRO, says it would take at least 15 years to build a large-scale nuclear power plant — and it would cost twice as much to produce electricity through nuclear reactors when compared with renewable sources.
Nuclear power generation has been banned since the 1990s, under laws passed by the Howard government.
Despite that, Shadow Treasurer Angus Taylor insists nuclear reactors are "commercially viable" and can be built without taxpayer subsidies.
Essentially, the argument is that the free market and private investors will decide to back nuclear because it will guarantee a return on investment.
We spoke to some of Australia's major energy companies, a billionaire investor, and fund managers to get their thoughts.
Radioactive unicorns
AGL Energy's CEO Damien Nicks said nuclear energy was not part of his company's plans.
"There is no viable schedule for the regulation or development of nuclear energy in Australia, and the cost, build time and public opinion are all prohibitive," he said.
"AGL is strongly focused on ensuring strong social licence with the communities and traditional owner groups where we operate and there remain significant unanswered questions about the cost and plans for radioactive waste.
"Policy certainty is important for companies like AGL and ongoing debate on the matter runs the risk of unnecessarily complicating the long-term investment decisions necessary for the energy transition."
Origin Energy, meanwhile, said the company was focused on renewables and battery storage.
"At this stage, our primary focus is adding more supply from these mature low-emissions technologies," Origin's spokesperson said.
"However we will continue to watch progress with any emerging technologies that may be able to contribute to emissions reduction over time."
Alinta Energy's CEO Jeff Dimery is not considering nuclear at all.
When he addressed the Press Club in April, Mr Dimery compared the federal opposition's plans to replace coal plants with nuclear power to "looking for unicorns in the garden".
He also dismissed the idea of using Alinta's LaTrobe Valley site or any other existing coal plant to build nuclear reactors.
"You could imagine our shareholders and our board wouldn't be too impressed if the management team was sitting around contemplating building power stations that are not legal. It wouldn't be a great use of our time."
Brett Chatfield, the chief investment officer of Cbus Super, is not convinced either.
When asked if nuclear would form part of his company's investment portfolio should the Coalition win the next election, he said: "We don't see nuclear as really a part of the energy transition going forward."
"We're much more focused on the renewable area — offshore and onshore wind, and solar as well."
Cbus manages over $85 billion worth of retirement savings for more than 910,000 Australian workers.
Nuclear doesn't 'stack up'
The executive chairman of Fortescue, Andrew Forrest, is one of Australia's largest investors in renewable energy and green hydrogen in recent years.
He is also against the idea of Australia pursuing the nuclear option because he believes it is the most expensive form of new energy and the slowest to build.
"I'm technology agnostic, I simply want to see fossil fuels removed from Australia's energy mix as soon as possible, but as an industrialist, I've looked at nuclear and it does not stack up," he said.
"We cannot let politicians, trying to use a point of difference to get elected at any cost, set our country back when we have such a huge opportunity in front of us."
Mr Forrest said a mix of large-scale wind and solar projects, paired with storage and in addition to green hydrogen, was the fastest and cheapest way to lower the cost of energy for all Australians.
"Business needs the public to speak loudly because the oil and gas lobbyists have strangled opposition for 100 years and now it's life and death," he said.
"We must not allow them to cripple green energy and give them a free hand to destroy the planet."
'Virtually impossible' to build without subsidies
The head of global infrastructure at IMF Investors, Kyle Mangini, said it was "virtually impossible" for the private sector to take on the financial risk of building nuclear reactors without taxpayer subsidies.
"If you look at where the nuclear facilities are being built globally, they're almost in all cases being built by governments," said Mr Mangini, who manages $110 billion worth of energy and infrastructure investments in his role.
"In Australia, there's never been a nuclear facility built, so there's no skilled labour force.
"And that's just the beginning; a nuclear facility would need a very long-dated sales contract to sell the power – something like 30 years at a fixed price. That doesn't exist in this market.
"And the nature of these facilities is that it's extremely difficult to get someone to build it for you on a fixed-price basis."
He also said: "It's extremely difficult to forecast with any accuracy what the costs will be."
Mr Mangini was referring, in particular, to the Hinkley Point C nuclear plant currently being built in Somerset, in south-west England. The build is running late and significantly over budget.
Hinkley was supposed to cost $35 billion over a nine-year construction period and start generating power in 2025.
However, that is now expected to blow out to as much as $88 billion over 15 years, which means it might not be operational until 2031.
Worldwide, nuclear construction projects have had a tendency to experience lengthy delays and cost blowouts.
Data from the International Energy Agency (IEA) shows that, on average, China's nuclear reactors since 2007 have taken two years longer-than-expected to build. While in North America, the delay has been the longest at more than six years.
Mr Mangini also said another reason why nuclear was not an attractive investment was the unknown cost of radioactive waste removal.
"If you don't have a clear path through to disposal, then essentially what you have is a liability that you can't value. It's going to cost you something, but you don't know what that's going to be."
'Significant need' to invest in nuclear
Despite the financial risks of investing in nuclear, Maple-Brown Abbott portfolio manager Phillip Hudak believes it is important to Australia meeting its emissions reduction targets.
"Subsidies are an important element to get the shift going," he said.
"We're seeing that in wind and solar, and there is no exception that nuclear would need subsidies from government to be successfully rolled out."
In order for private investors to earn a return from nuclear investment, Mr Hudak said: "Government subsidies need to be in place at the start, given the lack of technology and skill availability that we have here in the Australia market.
"But the expectations that we would see is a higher level of efficiency come through as nuclear reactors rolled out here in Australia."
The world's energy consumption is expected to skyrocket in the coming decades, particularly due to increasing use of electric cars, artificial intelligence and data centres.
That is why Mr Hudak says nuclear would play a key role in providing "reliable base load power" as a backup when renewable energy sources failed.
'Entirely unproven'
The biggest problem of nuclear energy is "the technology in the Australian context is entirely unproven", according to Climate Energy Finance director Tim Buckley,
"We don't have any of the supply chains, any of the labour, skilled workforce or knowledge to actually do it," he said.
He said it was "impossible" for any private investor (without taxpayer subsidies) to take on the risk of building a nuclear power plant.
"When we look at the American market, nuclear power plants are underwritten by a multi-decade government off-take agreement, so the pricing is set," he said.
"When you look at the UK, Hinkley Point is underwritten by a 30-year government price support scheme that starts at something like $200 a megawatt hour and then goes up at [the rate of] inflation for 35 years, or 3.5 per cent, whichever is lower.
Essentially, Mr Buckley says power generated from nuclear reactors is the most expensive option for Australia – unlike renewable sources, which are seeing the cost of energy production fall by "double-digit" percentages per year.
"So it's bizarre that anyone would claim nuclear could be built in Australia without massive multi-decade government financial support," he said.