Green hydrogen stands as a linchpin in the energy transition, yet its precarious transport poses a quandary. Could ammonia be the solution, or does it carry a hidden environmental toll?
Ammonia (NH3), derived from hydrogen and nitrogen, emerges as a potential savior. Its transport via ship or pipeline offers advantages. Subsequently, ammonia can be burned directly or converted back into hydrogen.
Ammonia’s Role in Energy Policy
Both the German government and the scientific community champion ammonia. Professor Michael Sterner of the Technical University of Regensburg deems “green ammonia” a promising energy source, enabling the harnessing of renewable energy from remote areas. This, he believes, could create value-based energy partnerships benefiting the Global South and ensuring Germany’s energy needs.
Ammonia’s importance echoes in LNG terminals on the North Sea and Baltic Sea, designed for potential conversion to hydrogen or ammonia. However, a pivotal study by US researchers, published in “PNAS,” spotlights environmental risks associated with ammonia.
Unveiling Health and Climate Hazards Linked to Ammonia
Ammonia, during production, conversion back into hydrogen and nitrogen, and incomplete combustion, releases substantial amounts of reactive nitrogen compounds, including NH3, nitrogen oxides (NOx), and nitrous oxide (N2O).
Nitrogen oxides pose health risks, contributing to fatal respiratory diseases. Notably, nitrous oxide, as per the Federal Environment Agency, wields around 300 times the climate impact of carbon dioxide.
Agriculture traditionally leads to nitrogen emissions. The energetic use of ammonia could, in the worst-case scenario, add half of the current agricultural emissions. Researchers estimate nitrogen escape during production to combustion to range from 0.5 to 5 percent.
Ammonia’s Climate Footprint
To mitigate ammonia emissions, extensive research is imperative. Heidi Heinrich from Forschungszentrum Jülich underscores the complexity, stating that regulating ammonia emissions requires capturing them. However, the study reveals challenges — measuring ammonia leakage is feasible only for a few hours, necessitating a costly, globally comprehensive surveillance system.
As green hydrogen seeks efficient transportation solutions, the ammonia dilemma unfolds, emphasizing the pressing need for research, regulation, and environmental accountability. Balancing the promise of ammonia against its potential hazards becomes pivotal in shaping a sustainable energy future.