An energy consultant says transitioning Australia's energy network to net zero with only renewables will cost 10-20 percent more than a combination of nuclear, biomass, and energy technologies.
At a recent parliamentary inquiry into Australia adopting nuclear energy, Geoff Bongers, director of Gamma Energy Technology and a professor at the University of Queensland, spoke about the trade-off between decarbonising, and continuing with traditional fossil fuel sources.
"If cost is your only metric, [then] keep unabated coal-it has served us well [and] it is cheap. However, when we add the complexity of having decarbonisation, unabated coal becomes problematic, [and] unabated gas becomes problematic," he told the Select Committee on Nuclear Energy.
"When we decarbonise, it is going to cost us more. Whichever way we decarbonise, it's going to cost us more than the current environment, which doesn't help with cost of living pressures."
The director also noted that if Australia were to decarbonise 80 percent of its emissions, a pure renewable-only grid would be more expensive.
He explained that many industries had a significant electricity demand, and some, such as the aluminium industry and green hydrogen, were highly dependent and sensitive to electricity prices.
"From that point of view, energy is a really important input into industry," Bongers said.
"If we disproportionately increase our cost compared to others who are using a mix to get the lowest total system cost, if we choose to eliminate a technology or two, that results in a higher overall cost of being able to deliver the system we want to deliver.
"You don't want a soccer team full of goalies. You don't want a soccer team full of strikers. You don't want a soccer team full of big fieldmen. You actually need a balance," he said.
The director added that a proper power network needed to be backed up by low-emission energy sources like gas or nuclear.
"I'm not saying that our future grid needs to be 20 gigawatts worth of nuclear. I'm not saying that we should only have 10 gigawatts of wind and solar," he said.
"A future grid is likely to have probably 15 to 20 gigawatts of dispatch or low emission technology. The rest of it is likely to be wind and solar, probably double, or triple that at least."
According to Bongers, an example of low-emission energy technology is gas turbines
Further, the director highlighted the importance of ensuring different energy sources complemented each other as grid expands and becomes more complex.
"The more wind and solar that we have, and the more batteries we have, the clearer we will need to be to make sure those technologies work together well," he said.