For decades, economists and chemists alike have been dreaming of a hydrogen economy, where hydrogen fuels our global power. But is this revolution really ‘just around the corner’ as some proclaim? New research published in Energy and Environmental Science from chemical engineers at UNSW Sydney and the University of Sydney suggests it may be closer than ever.
The study describes the development of a new way to produce ammonia from the air. In addition to being at the crux of synthetic fertilizer production, ammonia also offers a way to safely store and transport hydrogen energy. But ever since manufacturing of ammonia began back in the early 20th century with the Haber-Bosch process, ammonia production has required high temperatures and pressures – all resulting in its production being extremely energy-intensive.
"The current way we make ammonia via the Haber-Bosch method produces more CO2 than any other chemical-making reaction," explains Dr. Emma Lovell, a co-author on the paper from UNSW's School of Chemical Engineering. "In fact, making ammonia consumes about 2 percent of the world's energy and makes 1 percent of its CO2 - which is a huge amount if you think of all the industrial processes that occur around the globe."
Even more energy is expended in the transport of ammonia around the world from the few large, centralized infrastructures that can currently produce it cost-effectively. To right this, Dr. Lovell’s team wanted to figure out how to produce ammonia inexpensively, and on a smaller scale, relying on renewable energy.
"The way that we did it does not rely on fossil fuel resources, nor emit CO2," Dr. Lovell says. "And once it becomes available commercially, the technology could be used to produce ammonia directly on-site and on-demand - farmers could even do this on location using our technology to make fertilizer - which means we negate the need for storage and transport. And we saw tragically in Beirut recently how potentially dangerous storing ammonium nitrate can be. So if we can make it locally to use locally, and make it as we need it, then there's a huge benefit to society as well as the health of the planet."
The new “green” method of producing ammonia has been shown possible in a laboratory-based proof of concept. The team will soon take steps to make their method commercially available in order to introduce the technology to the world.