Early this year, several announcements were made regarding hydrogen research and development in Australia. While Australia is well-placed to develop a booming hydrogen economy, experts from the Faculty of Engineering at University of Sydney believe that hydrogen energy remains a difficult technology to master and there are several challenges that must be overcome to achieve broad-scale uptake of hydrogen energy.
So what does Australia need to do to transition to a true hydrogen economy?
Understanding hydrogen and its opportunities
Professor Jun Huang from the School of Chemical and Biomolecular Engineering believes hydrogen has the potential to power the future green economy.
“Hydrogen is a clean fuel and burning it only generates water and, unlike the burning of coal, there are no CO2 emissions,” said Professor Huang.
An expert in hydrogen engineering and CO2 conversion, he explained that while hydrogen is the most naturally abundant element on earth, hydrogen fuel doesn’t occur in nature. Instead, it requires a chemical or electrochemical process to produce on an industrial scale.
“Australia has an outstanding opportunity when it comes to hydrogen, being plentiful in natural gas and coal. However, the prize of renewable hydrogen lies in harnessing solar energy on a large enough scale to use renewable electricity in the conversion of water to hydrogen.”
Challenges of cost and access to water
According to Professor Huang, the conversion of water to hydrogen using electricity is a clean process. The challenge, however, comes from the costly process, which demands a large amount of electricity. Since most of this energy is generated from non-renewable sources, hydrogen energy is not yet truly ‘clean energy’.
“The price of industrial electricity in Australia is also several times higher than in Europe, the United States and Asia, which will result in the higher cost of Australian hydrogen production and lower competitiveness of Australian hydrogen in the global market,” he said.
Australia needs to not only work out how to reduce the running cost for power generation and upgrade the power grid to make way for hydrogen, but also resolve the issue of access to fresh water required for the production of hydrogen energy.
“Because of these challenges, hydrogen production using electricity is only in its infancy. We will only be able to progress to large-scale commercialisation once these issues have been successfully addressed,” Professor Huang added.
A solution for 'hydrogen embrittlement'
Dr Yi-Sheng ‘Eason’ Chen is an expert in hydrogen energy from the School of Aerospace, Mechanical and Mechatronic Engineering and the Australian Centre for Microscopy and Analysis. Australia's ability to use hydrogen as an effective energy carrier will critically underpin whether or not a decarbonised energy portfolio is achieved, he said.
“The transport and transmission of hydrogen is an essential part of this; however, there are significant challenges which must be addressed. Our current national plan is to use the existing infrastructure from the natural gas sector – high-pressure pipelines and storage containers made of metals, predominantly steels," said Dr Chen.
“However, hydrogen is detrimental to metals – a physical phenomenon we call 'hydrogen embrittlement'. What this means in simple terms is it can destroy metal and make it brittle, destroying pipelines and vessels intended to transport and contain it. So far there's no evidence to show that our existing infrastructure is compatible for carrying hydrogen effectively.
"My research aims to address issues surrounding hydrogen embrittlement and find a solution for its transport. At the University of Sydney, we use a state-of-the-art microscope, known as cryogenic atom probe tomography (CryoAPT) that can unambiguously map how hydrogen interacts and moves in materials.
“CryoAPT can be used to study the behaviour of hydrogen, allowing us to understand how hydrogen leads to the embrittlement and how we can prevent it, which is an essential component to enabling a hydrogen future."
Image: Working together, solar and hydrogen energy could power a future renewable market. Credit: Pixabay