Researchers from the Australian National University (ANU) are raising the alarm over the federal government’s promotion of producing hydrogen that uses fossil fuels as a carbon emissions reduction ‘plan’, warning that it could create an industry that leads to an increase in greenhouse gas emissions.
In a recent study published in the journal Applied Energy, ANU academics have suggested emissions from fossil fuel-based hydrogen production could be ‘substantial’ even with carbon capture and storage (CCS) technologies.
One of the study’s co-authors, Dr Thomas Longden from ANU’s Crawford School of Public Policy, explained that Australia’s strategy (which was only released last month) remained ambiguous on just how beneficial the proposed hydrogen sources for the environment would be. This is because, as Longden describes it, the plan uses the term ‘clean hydrogen’ without making the distinction between green and blue hydrogen.
Green hydrogen refers to hydrogen made by renewable energy-driven electrolysis, while blue hydrogen is made from natural gas with CCS technologies.
“By using the term ‘clean’ hydrogen for both renewable-based and natural gas-based hydrogen, the danger is that we could establish a hydrogen industry that actually leads to an increase in emissions,” Longden said.
In the case of blue hydrogen, the academic argued it was possible for this form of hydrogen to drive down emissions in Australia — but was also a very expensive way of doing so.
“Mature CCS technologies could avoid between 50% and 90% of the emissions, but they are expensive, and become more expensive as the capture rate increases,” Longden added.
Co-author Dr Fiona Beck, from ANU’s school of engineering, said that Australia’s net-zero by 2050 plan must consider the negative consequences of ‘fugitive emissions’ (a potent greenhouse gas). She also stressed that a plan that relied on CSS had the effect of increasing fugitive emissions further, as more natural gas was required to fuel the process. Fugitive emissions are the second-largest source of methane pollution in the world.
“Our work highlights that large investment in fossil fuel-based hydrogen with CCS could be risky, locking in a new fossil fuel industry with significant emissions, and one that is likely to be out-competed by renewable technologies in the future,” Beck said.
“Hydrogen made from natural gas leads to more fugitive emissions – methane that is leaked into the environment during the extraction and processing of natural gas – compared to just burning natural gas directly,” she said.
Australia was not among the 100 countries to sign up to the Global Methane Pledge, a project jointly led by the EU and US with a view to cutting global methane emissions by 30% by 2030.
“We need to rapidly reduce methane emissions to have a chance of limiting global warming to below 1.5 degrees Celsius,” Beck said.
“Developing a new, large-scale, low-emissions hydrogen industry based on natural gas undermines these efforts and ignores the dangers that fugitive emissions pose to our environment.”
Dr Longden underscored that even if CSS technologies were to become more feasible (and affordable), it could not prevent figurative methane emissions from being released into the atmosphere. A national hydrogen strategy should not stay silent on the issue of fugitive emissions, he said, especially because the use of natural gas will still release a potent greenhouse gas.
“Electrolysis with renewable energy could become cheaper than fossil fuels with CCS,” Longden said.
“CCS is an expensive option for emissions reduction, with most estimates for the cost of carbon capture being above $82 per tonne of carbon dioxide (CO2). These estimates increase to about $109 per tonne of CO2 for high capture rates,” he said.