CSIRO puts cost of new nuclear plant at $8.6bn as Coalition stalls on policy details

<span>The CSIRO’s calculations show that electricity generated from nuclear power plants is more expensive than expanding renewables, including transmission infrastructure. </span><span>Photograph: Roni Bintang/Getty Images</span>
The CSIRO’s calculations show that electricity generated from nuclear power plants is more expensive than expanding renewables, including transmission infrastructure. Photograph: Roni Bintang/Getty Images

Electricity from nuclear power in Australia would be at least 50% more expensive than solar and wind, according to a report from the CSIRO that has for the first time calculated costs for large-scale reactors.

The federal Coalition, which has claimed nuclear would provide cheap electricity, is still to reveal any details on its nuclear policy after initially promising it would make an announcement in time for last week’s federal budget.

This week the opposition leader, Peter Dutton, said more plans would be released “in due course” and has yet to say where plants might be built or how large they would be.

The Coalition would first have to overturn a federal ban on nuclear power. Several state government bans also exist.

According to CSIRO’s GenCost report, a theoretical 1000MW nuclear plant built today would cost at least $8.6bn.

The report said nuclear costs in that range “can only be achieved if Australia commits to a continuous building program and only after an initial higher cost unit is constructed”.

The capital costs of a large nuclear plant could double in a country that has never built a large reactor before, the report said.

Such a “first-of-a-kind” premium could also apply to other technologies not yet used in Australia, including offshore wind, fossil fuel plants with carbon capture and storage, or solar thermal.

A combination of solar and wind power remained the cheapest source of electricity, the GenCost report said, even allowing for the extra costs of integrating them into the grid.

Those costs included building extra transmission lines and adding storage, such as batteries and pumped hydro, so that power from solar and wind can be released on demand.

By the year 2030, the report said electricity from a combination of solar and wind would cost between $73 and $128 a megawatt hour, depending on how much renewable energy was already in the system.

This compared to large-scale nuclear at $141 to $233/MWh and $230 to $382/MWh for small modular reactors.

Related: Coalition MPs dismiss International Energy Agency advice to ditch nuclear plans

Also cheaper than nuclear power, according to the report, was gas-fired electricity with carbon capture and storage and solar thermal electricity – a technology where mirrors concentrate the sun’s energy to create intense heat that can be stored.

The CSIRO report said to achieve the lower end of cost estimates for coal, gas and nuclear technologies, plants would have to run at 89% of their capacity “when historically coal, which has been the main baseload energy source in Australia’s largest states, has only achieved an average of around 60%”.

On Tuesday, the renewable industry’s Clean Energy Council released a report claiming nuclear energy was up to six times more expensive than solar and wind.

The GenCost report has come under intense scrutiny in recent months, in particular from nuclear advocates.

In March CSIRO chief executive, Douglas Hilton, staunchly defended the report from “unfounded criticism” after Dutton claimed it had been discredited.

CSIRO received 45 submissions in response to a draft of the report – more than four times the usual amount – with the majority coming from private individuals. Most of those private submissions had requested CSIRO include the costs for nuclear.