Powering Up: A Look at Fossil Fuel Alternatives

Powering Up: A Look at Fossil Fuel Alternatives

The Hydrogen Economy is starting to wane as cleaner energy sources catch the public eye.

When people think about fossil fuel alternatives, ammonia is not one of the things that first comes to mind. The product is better known as a part of a household cleaner or as a fertilizer. But with the public clamoring for cleaner ways of providing energy, researchers and businesses are taking a long, hard look at “the other natural gas.”

Hydrogen has long been viewed as one of the key role players in greenhouse gas reduction. According to a study by carbon-free energy solutions provider Amogy, more than 1,000 large-scale hydrogen projects worldwide have been announced, amounting to a $320 billion investment. 

By 2050, hydrogen could contribute to a 20 percent reduction in global emissions. The potential of this powerful—and plentiful—element is impossible to ignore, according to Amogy Senior R&D Strategy Analyst Poornima Natarajan.

Amogy hydrogen 300

With a few scientific tweaks, green hydrogen, produced using renewable electricity, can be converted to green ammonia, a more-efficient and environmentally safer gas for heat generation. Credit: Courtesy Amogy

But despite being one of the world’s cleanest-burning energy solutions, “The Hydrogen Economy” is being held back by availability. Generating hydrogen in a pure form requires separating it from other elements such as oxygen or nitrogen. It’s an energy-intensive and sometimes emission-heavy effort, too. 

Storing pure hydrogen is expensive and requires a lot of energy to pressurize or refrigerate. It’s also highly flammable, colorless, odorless, and near-invisible when burning, making it difficult to detect in the event of a leak or fire, Natarajan notes.

Amogy research

Transitioning from fossil fuels to renewable and sustainable energies, according to Amogy CEO Seonghoon Woo (center), is "the issue of of our lifetime." Image credit: Amogy

Powered by Ammonia? 

In contrast, ammonia has 2.7 times the energy density of compressed hydrogen, can be easily stored as a liquid, and requires significantly less energy to store and transport safely. Ammonia is also the world’s second-most-produced chemical and it is also far less flammable than hydrogen. In the event of a leak, ammonia is much easier to detect thanks to its strong and distinctive odor.

“Ammonia is an easy way to transport hydrogen over long distances, and its widespread use in agriculture means there is already an established infrastructure for producing and moving it,” notes Matteo Bertagni, a postdoctoral researcher at Princeton’s High Meadows Environmental Institute. “You could therefore create hydrogen in a resource-rich area, transform it into ammonia, and then transport it anywhere it’s needed around the globe.” 

According to Young Suk Jo, Amogy’s chief technology officer and co-founder, the key to using ammonia—especially in high-demand areas such as transportation—is to pull it apart. A company-developed chemical reactor—a “cracker”—breaks ammonia down into nitrogen, which can be safely released into the atmosphere, and hydrogen. That hydrogen can then be used in a fuel cell to produce electricity.


The key to making ammonia a beneficial energy source is to break or “crack” it into nitrogen and hydrogen. Credit: iStock/vchal

“We believe that introducing a clean energy source for the hard-to-abate sectors is not only needed but is also urgent,” notes Amogy CEO Seonghoon Woo. “With our planet’s natural ecosystems, biodiversity, climate stability, and air quality at stake, we envision a cleaner, sustainable future with ammonia at the source.”

Amogy has focused its ammonia-to-energy effort primarily on maritime applications. But in April, the company entered a partnership with Norwegian electricity-driven heavy builder products maker Terox to begin generating electricity at construction sites. 

“This [marks] a significant step towards sustainable energy solutions in the construction industry,” says Kjell Vidar Hamre, managing director at Terox. “We are looking forward to showcasing the viability of ammonia-based power systems and contributing to the decarbonization of the construction industry.”

Environmental “Bad Guy” Makes Good

Ammonia is not the only gaseous element being put to new use. Milan, Italy-based Energy Dome has constructed a pilot energy storage plant in Ottana, Sardinia that uses carbon dioxide (CO2) to help supply the local energy grid. 

Energy Dome rendering - Alliant

Energy Dome’s innovative power plant turns carbon dioxide into an emissions-free energy source that can power thousands of homes. Credit: Courtesy Alliant Energy

Put simply, excess electricity from nearby solar and wind power farms is used to compress CO2 into liquid, which is then stored in carbon-steel tanks. When power is needed, the liquid is run through an evaporator and turned back into a pressurized gas. The gas is sent through an expansion turbine, where it rapidly expands to drive an energy-generating rotor. Some of the power generated during this process goes back to the outside grid.

The uncompressed CO2 is then stored in a flexible, inflatable “energy dome” at ambient temperature and pressure for later re-use. 

In effect, it’s a self-perpetuating giant battery that generates clean energy in part by using climate change-inducing CO2. There are no emissions into the atmosphere, the dome’s key components—steel, water and CO2—are easily available, and overall costs are low. Multiple energy dome plants worldwide would be possible, according to company CEO Claudio Spadacini.

“We have a simple yet powerful mission in mind: we want to help start decarbonizing the world today because our world can’t wait,” he notes. “How many companies can say they have the technology to change the world today?  We can, and we want to do it for our future and the future of our children.”

The company is now building a commercial-scale dome in Portage, Wisc., that can hold more than 40 times as much CO2-derived energy vs. the adjacent pilot model. The 200- megawatt-hour plant, which is capable of supplying power to about 20,000 homes for 10 hours, is expected to be fully operational by 2026.