Pumped hydro and battery storage can enable Australia to meet its energy needs without increasing the use of gas to fuel electricity plants, according to a new paper by researchers at The Australian National University (ANU).
The research finds the National Electricity Market could become a low-cost, zero emissions grid without depending on fossil gas.
Australia is planning to increase gas-powered generator capacity to 17 gigawatts by 2050 - the same year we are expected to meet our net-zero greenhouse gas emissions target.
"A persistent narrative suggests that this gas is essential for balancing solar and wind beyond 2050, but our new study shows that long-duration pumped hydro plus batteries can do the same job at the same cost, minus the carbon emissions," said lead author Timothy Weber, of the ANU Centre for Energy Systems.
"We evaluated seventeen institutional long-term energy plans and found they skewed towards fossil gas since they used methods that constrained storage cycling, overlooked off-river pumped hydro potential, and ignored near-optimal energy transition pathways.
"In a post-2050 Australian electricity grid case study, we found near optimal 100 per cent renewable solutions."
The researchers also developed a planning model which showed batteries and long duration pumped hydro could replace gas without incurring a cost penalty.
"Since most regions have sufficient 50-5000 gigawatt-hour pumped hydro options, adjusting modelling practices will help planners design 100 per cent renewable grids using existing technologies," Weber said.
Professor Kylie Catchpole said although gas was often hailed as cleaner than coal, recent research demonstrated that the risks were significantly underestimated and, with enough leaks, could be worse for the climate.
"As well as carbon emissions from combustion, gas produces fugitive methane emissions which have a global warming potential 83 times higher than carbon dioxide over a 20-year horizon," Professor Catchpole said.
"There are currently no commercial gas-powered generators operating with carbon capture and storage anywhere in the world.
"It makes more sense for Australia to develop 100 per cent renewable electricity systems balanced by pumped hydro and batteries."
The paper is published in Cell Reports Physical Science .
