Net zero nuance: commentary on decarbonising the grid misses the mark on batteries and nuclear

Commentary on decarbonising Australia’s electricity network seems to be heading towards net zero nuance, with questionable claims about the costs of batteries and nuclear power in the past week.

One claim relies on an estimate of the cost of a multibillion-dollar nuclear plant that doesn’t exist yet, and another puts a multitrillion-dollar figure against the cost of building batteries.

First to nuclear power, which, we should remember, has been effectively banned in Australia since the late 1990s.

Related: The Paris-sized blind spot in the Coalition’s climate target debate | Temperature Check

On page three of the Sunday Telegraph in Sydney, columnist Piers Akerman wrote an “exclusive” news story showing “nuclear energy is cheaper” than coal, gas, solar or wind.

Such a claim would overturn pretty much all serious analysis of electricity costs around the globe. So where did it come from? The International Energy Agency maybe, or perhaps the CSIRO?

No. Akerman quoted “new data” from Tony Irwin, who is a nuclear industry veteran and a technical director at a consultancy company with “specialist industry knowledge on the procurement and development of nuclear technologies” with a focus on small modular reactors (SMR).

According to Akerman, Irwin’s data showed “nuclear-generated power” costs $5,596/kW to build, compared with $14,882 for large-scale solar, $12,372 for wind and about $10,000 for coal and gas, both with carbon capture and storage attached.

The Nationals leader, David Littleproud, who wants to see nuclear power considered in Australia, tweeted a link to the story saying: “Perhaps nuclear isn’t a dirty word after all?”

But one problem with using Irwin’s numbers is they are based on an estimate of the cost of one particular SMR design which has not yet been built and won’t produce power until at least 2029.

The estimate comes from a US-based company that’s trying to build its SMR in partnership with Utah Associated Municipal Power Systems which has budgeted more than $8.5bn for the plant. In 2020, the US Department of Energy approved up to $2bn of funding to back it.

SMRs have not yet been commercialised. The name might suggest they’re neat and off-the-shelf, but while dozens of designs and development projects are in existence, they are not something any government can currently go out and buy and plug into their electricity grids.

Related: The Coalition didn’t do much on nuclear energy while in office. Why are they talking about it now?

Irwin told Temperature Check the numbers had been published on the consultancy’s website in October 2021, and provided a link.

His calculations included “adjustments” for the percentage of time each type can produce electricity, the lifetime of plants and how flexible they are, which significantly pushes up the cost of all other forms of electricity except SMR nuclear.

The CSIRO’s latest draft of its GenCost report that explores how much different electricity sources will cost says there is no prospect of an SMR plant being built in Australia before 2030.

By then, it estimated a cost of between $7,700/kW and about $17,000/kW – at least five times the cost of large-scale solar in 2030.

The GenCost report says, by 2030, the costs of other electricity generation and supply – including large-scale solar, wind and especially batteries – will have dropped even further.

The secretary of the Victorian branch of the Australian Institute of Energy, Glenne Drover, who is a broad supporter of nuclear power, told Temperature Check the costs of SMR reactors were “still speculative” and it would take about five years before the actual costs became clearer.

He said nuclear power “should play a vital role in decarbonisation for countries that are not blessed with the space, wind and sun that Australia has”.

“So we might never need it, but we probably need to wait to 2030 to see how the renewables decarbonisation plan is going.”

Dud battery charge

Would it really cost $6.5tn to power Australia only on batteries, and are any electricity system experts seriously suggesting that’s what they’re for?

The short answers are no, and no. Yet this figure has been used at least twice in commentaries this month.

In a column arguing “the transition to net zero emissions will be hard and expensive”, the Nine News political editor, Chris Uhlmann, said whatever technology was used to support renewables “won’t be cheap” and pointed to a report that “calculated the cost of battery storage for Australia at $6.5tn”.

Related: Paying coal and gas plants to supply back-up energy a ‘retrograde step’, Clean Energy Council says

Last week, Claire Lehmann, a columnist in the Australian wrote: “The battery storage required to power the whole of Australia has been estimated to cost $6.5tn. If this is a cost-effective solution, then God help us all.”

So what’s the basis for this claim?

The figure comes from a 2019 report from Industry Super Australia. The authors took the cost of South Australia’s Tesla battery and, in a back-of-envelope calculation, extrapolated that battery’s capacity until it could power the entire electricity grid for a day and a half. That was 7.5TWh of electricity, the report claimed, although the authors said they were not suggesting “any attempt should be made to provide all back-up using batteries”.

Dr Dylan McConnell, an energy systems analyst at the University of Melbourne, said the use of the number was ​​a “strawman”, adding: “I can’t believe anyone still takes it remotely seriously.”

The Australian Energy Market Operator’s draft plan to decarbonise the national electricity market has said that by 2050, Australia will need about 620GWh of storage – which includes all storage technologies, including batteries and dams.

Expressed another way, that’s about 12 times less electricity than the figure being plucked from the Industry Super report.

McConnell said: “There is no justification for the requirement to store the entire grid’s worth of energy for 1.5 days. If that was a legitimate requirement, you wouldn’t try and meet that requirement with only lithium-ion batteries.”

Very bad paleo diet

Fossil fuels advocate Alex Epstein, a regular guest on Sky News Australia, last week enraged the climate science community by tweeting a chart tracking CO2 levels going back hundreds of millions of years in Earth’s history.

The all-time high is somewhere around 6,000 parts per million (current levels are 420ppm). Epstein said it would take emissions increasing until well past the year 2100 for levels to get to even a quarter of that level, and before which “we can expect to have ultra-cost-effective non-carbon nuclear energy”.

Regardless of what happens with nuclear energy, an important question to ask is what else could the planet expect if CO2 levels got up to 1,500 ppm?

Dr Georgy Falster, a paleoclimate scientist at the Australian National University, told Temperature Check: “The last time the atmospheric CO2 concentration might have been as high as 1,500ppm – about 3.5 times higher than it is today – was during the mid-cretaceous period, around 100m years ago.

“The paleo record suggests that at this time, the average global temperature was around 15C to 20C hotter than present – that’s at least double what it is today,” Falster said.

Related: Carbon dioxide levels are now 50% higher than during the pre-industrial era

“Global sea level was on average 75 to 250 metres higher than present-day mean sea level.”

Dr Ben Henley, a climate scientist at the University of Wollongong, said at just 1.5C to 2C of warming, “there will already be catastrophic consequences to many natural ecosystems and humankind”.

Recreating ancient climates with spiralling CO2 levels today would mean “practically every coastal city on Earth would be flooded and human communities would be decimated”, Henley said.

Epstein may be hoping those cheap nuclear power plants will be able to operate underwater, providing there are enough humans left that need air-conditioners.