Conventional production of ammonia (NH3) is a large scale industrial process, which uses hydrogen derived from natural gas. Currently 5% of global natural gas consumption is used to make ammonia (2% of world energy) causing it to contribute significantly to greenhouse gas emissions. Urea is a nitrogen-rich fertiliser made from ammonia and carbon dioxide. With the growing global population and demand for foodstuffs increasing, together with less acreage being dedicated to crop cultivation, 50% of global food production currently relies on the use of ammonia-based fertilisers to increase crop yields.
Ammonia and urea fertiliser can be produced sustainably by using hydrogen derived by electrolysis of water using a renewable electricity supply and a PEM electrolyser. This de-couples ammonia production from fossil fuels. In the case of urea, it also decarbonises the process further, as it provides a means of utilising waste carbon dioxide.
Renewable hydrogen offers decentralised local fertiliser production opportunities, which improve security of supply and crop yield for a growing world population as well as price stability (removing the link to fossil fuel price volatility).