Over the past 15 years,the cost of a megawatt per hour from solar PV has fallen from $US329 to $US61. Over that same period,nuclear power has increased from $US123 to $US181,the largest increase of any power source.

Lazard,however,argued that nations need to diversify their energy sources given the growing demand for power out of emerging sectors such as artificial intelligence,data centres and electrification of energy grids.

“The optimal solution for many regions is to complement new renewable energy technologies with a ‘firming’ resource such as energy storage or new/existing and fully dispatchable generation technologies,” it said.

Dutton noted that France has the cheapest power in Europe,with 70 per cent of its electricity generated from nuclear energy.

Last month,France’s spot electricity price went negative as cheap renewable energy flooded its power market. Combined with reduced demand over a weekend,French officials shut down three nuclear reactors because their power could not compete against ultra-cheap renewables.

Other parts of Europe are also turning off their nuclear reactors for periods of time because their power is expensive compared to renewables.

The main reason for the relatively high cost of nuclear is the expense of constructing new plants.

France,despite its long experience building nuclear plants,has struggled to meet cost and time targets.

The 1650-megawatt Flamanville 3 power plant on the Cherbourg Peninsula in north-west France completed fuel loading last month and is due to be fully operational by year’s end.

Construction started in 2007,with the aim of having it running by 2012 at a cost of €3.3 billion ($5.3 billion). Twelve years behind schedule,the estimated cost is now north of €20 billion.

Dutton has said the Coalition would use established technology to reduce costs,noting the AP1000 power plant designed by the Westinghouse Electric Company.

The Vogtle 4 nuclear plant opened in late March in the US state of Georgia. The 1100-megawatt power station complemented the Vogtle 3 facility,which was completed last year.

Both plants were finished seven years late. The original cost was $US14 billion ($21 billion),but Georgia Power estimated the eventual cost at between $US31 billion and $US35 billion.

Both are AP1000 power plants.

The Coalition says the plants will be owned by the federal government,which means taxpayers will be on the foot for them.

Rich Insight budget watcher Chris Richardson says if the plants fail to make a commercial rate of return then the entire cost will have to be shown in the federal budget.

The debt to pay for the plants will be taxpayer debt,and the interest bill on that debt will be paid by voters for decades.

“This will come at a cost to the taxpayer,you won’t be able to sweep it under the carpet,” he says.

The federal budget has to also make allowances for what are termed contingent liabilities which are assets or policies that pose a financial risk to the government.

The Lucas Heights nuclear site has three liabilities:asbestos contamination,the eventual disposal of nuclear waste,and worker exposure to radiation.

Seven nuclear power plants will have to be added to the government’s risk profile,and taxpayers will ultimately be responsible.

“There’s a financial risk and that has to be accounted. It doesn’t matter if it’s a tiny risk,because if something does go wrong,it’s going to be a large cost,” Richardson says.

The Coalition says it will create economic development zones near each plant for “manufacturing,value-add and high-tech” industries. Defence firms,critical mineral processors and data centres are expected to move to these sites with the offer of lower wholesale power prices.

Surrounding regions will be promised everything from upgraded rail links to airports,new hospitals,and schools. They will also share in investment funds,the earnings of which will flow to local community groups.

In both cases,there are no details on the cost to the budget,how they will operate or even from where the cash for the investment fund will come.

All the states home to the planned nuclear plants currently prohibit the energy source. Dutton,channelling former prime minister Paul Keating,said he “would not stand between the premier and a bucket of money” in an open suggestion he would try to buy states for a change in policy.

Again,there is no estimate of the cost of this or of the price attached to acquiring the property on which the nuclear plants would sit.

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