Ammonia: what would a green approach look like?

  • Advances in fertiliser production will play key role in meeting climate change objectives

  • Most importantly will be role production of those products plays in contributing to global carbon dioxide emissions

  • Phillip Cosgrave grassland agronomist at Yara answers questions about how the manufacturing process itself can change to an environmentally friendly approach

As climate change and sustainability becomes more and more a key driver for the agriculture industry, advances in fertiliser production will play a key role in helping us meet these objectives. Specifically, the role production of those products contributes to global carbon dioxide emissions and what can be done to change that. Achieving net-zero targets for carbon emissions by 2050 will require a substantial reduction in carbon dioxide production - and this will include the production of ammonia, a key ingredient in nitrogen fertiliser.


Is there a way in which the manufacturing process itself can change to an environmentally-friendly approach and help achieve this goal? Philip Cosgrave, Grassland Agronomist at Yara, believes so.


Philip Cosgrave, Yara UK says:

"Ammonia production and the net-zero target are not incompatible" says Philip. "Green ammonia production is an approach to the process of making ammonia that is 100% renewable and carbon-free."


We asked Philip some questions about what this alternative mode of production might look like and what it would mean for the industry.


Q: How would green ammonia production work?

There are several options. One way is by using hydrogen from water electrolysis and nitrogen separated from the air. These are then fed into the Haber process (also known as Haber-Bosch), powered by sustainable electricity. In the Haber process, hydrogen and nitrogen are reacted together at high temperatures and pressures to produce ammonia (NH3).


Q: What is the best way to reduce carbon emissions when making ammonia?

Using low-carbon hydrogen is the surest approach. Green hydrogen is produced using water electrolysis to generate hydrogen and oxygen. The only limiting factor for the production capacity of green hydrogen is the availability of sufficient green energy.


Q: Are there any consequences to this alternative approach?

Yes. A decarbonised ammonia production does make it impossible to produce urea. Urea is made by combining ammonia and the carbon dioxide (CO2) released earlier in the current process, when hydrogen is split from the carbon source (usually natural gas) to provide the hydrogen in ammonia (NH3) production. It’s unlikely urea could be part of a decarbonised food chain.


Q: What are fertiliser manufacturers doing to aid this green approach?

Yara's goal is to decarbonise fertiliser production. Naturally, this will require significant ongoing investment in R&D and production capacity. Interestingly, when Yara first began producing nitrogen fertiliser back in 1905 when it was founded in Norway, the process was carbon free! The energy source used then was hydro-electricity. The net-zero target is, in many ways, part of our DNA.