UNIVERSITY OF THE NEW SOUTH WHALES
UNSW Sydney engineers cracked the green hydrogen production cost numbers to show that Australia is in the best position to harness the green hydrogen revolution, with its vast solar resource and export potential.
The researchers identified the key factors needed to reduce the cost of green hydrogen and become competitive with other methods of producing hydrogen using fossil fuels.
In an article published today in Cell Reports Physical Science, the authors show how various factors affect the cost of producing green hydrogen through electrolysis using a special solar system and without additional electricity from the grid.
Without electricity from the grid, which is mainly fed from fossil fuels, this method produces hydrogen with almost zero emissions. Being off-grid also means that such a system can be used in remote locations with good, long-term solar radiation.
Researchers examined a number of parameters that could affect the final price of hydrogen green energy, including the cost of electrolysers and photovoltaic solar (PV) systems, the efficiency of the electrolyser, the amount of sunlight available, and the size of the systems.
In thousands of calculations with randomly assigned values for different parameters in different scenarios, the researchers found that the cost of green hydrogen ranged from $ 2.89 to $ 4.67 per kilogram (A $ 4.04 to A $ 6.53). It was possible to get even lower, the researchers said, with suggested scenarios approaching $ 2.50 per kilogram (A $ 3.50). From this point on, green hydrogen begins to become competitive with fossil fuel production.
WHY A PRICE SERIES?
Co-author Nathan Chang, a postdoctoral fellow at UNSW's School of Photovoltaic Renewable Energy Engineering, says a common problem with estimating the cost of developing technology is that calculations are based on assumptions that may only be for specific situations or circumstances be valid. This makes the results less relevant to other locations and does not take into account that technology performance and costs will improve over time.
"But here we get not just a single calculated number, but a series of possible numbers," he says.
"And every single answer is a combination of many possible input parameters."
“For example, we have updated data on the cost of PV systems in Australia, but we know that in some countries they pay a lot more for their systems. We have also seen PV costs decrease every year. So we added lower and higher cost values to the model to see what would happen to the cost of hydrogen.
“After we put all these different values in our algorithm and got a series of prices for hydrogen energy, we said, 'Okay, there have been a few instances where we got this $ 2 (AUD 2.80) each Kilograms approached. What was it about these cases that made it so low? & # 39; ”
The co-author Dr. Rahman Daiyan, of the ARC Global Hydrogen Economy Training Center and UNSW's School of Chemical Engineering, said that while investigating the cases where the cost per kilogram approached $ 2, certain parameters were noticed.
"Electrolysers' capital cost and efficiency still determine the viability of renewable hydrogen," he says.
“A key way to further reduce costs would be to use inexpensive transition metal-based catalysts in electrolysers. Not only are they cheaper, but they can even outperform catalysts currently in commercial use.
"Studies like this provide inspiration and goals for researchers working in catalyst development."
IT ALL ADDS UP
The system and cost simulation model itself was created by student Jonathon Yates, who was given the opportunity to work on the project through UNSW's Taste of Research scholarship program.
“We used real weather data and determined the optimal size of the PV system for each location,” he says.
“We then saw how this would change economics in various places around the world where solar powered electrolysis is being considered.
“We knew that each location where such a system would be installed would be different – require different sizes and different component costs. When these are combined with weather fluctuations, some locations have a lower cost potential than others, which can indicate an export opportunity. "
He points to the example of Japan, which does not have a large solar resource and may be limited in size.
"There may be a significant difference in cost compared to the vast outback regions of Australia, which have lots of sunlight," says Yates.
The researchers say it's not far-fetched to imagine large-scale hydrogen power plants becoming cheaper than fossil-fuel plants over the next few decades.
"As the PV costs fall, the profitability of solar hydrogen production changes," says Dr. Chang.
“In the past, the idea of a remote-controlled solar-powered electrolysis system was seen as far too expensive. But the gap is narrowing every year, and in some locations there will be a transition point sooner rather than later. "
Dr. Says Daiyan, "With technological improvements in electrolyzer efficiency, the expectation of lower costs to install these types of systems, and the willingness of governments and industry to invest in larger systems to take advantage of economies of scale, this environmentally friendly technology is moving closer to being competitive with alternative production Hydrogen from fossil fuels. "
According to Yates, it is only a matter of time before green hydrogen becomes more economical than hydrogen made from fossil fuels.
“If we recalculate the cost of hydrogen based on other researchers' projections of electrolyzer and PV costs, the cost of green hydrogen could drop to $ 2.20 per kg (A $ 3.08) by 2030, which is the same or cheaper than the cost of fossil fuels produced hydrogen.
"In this case, Australia, with its large solar resource, is well placed to take advantage of this."