Clean ammonia: a systematic overview of a super-leverage point

Ammonia is the backbone of global food systems, but it is also the most polluting chemical industrial process on our planet in terms of CO₂ emissions. Decarbonising ammonia production is an important lever that could eliminate 2% of current global emissions. 

Clean ammonia has also been identified as a promising carbonless energy vector to facilitate storage and energy transport in the energy transition and fuel for shipping, aiding in decarbonising one of the most ‘hard-to-abate’ sectors. Green Ammonia is expected to play an essential role in global decarbonisation. 

But these sectors don’t exist in isolation - zero-emissions solutions like Nium’s mighty minion reactor can influence multiple sectors simultaneously. 

A cascade of tipping points 

A recent report by Systemiq, University of Exeter [1], identifies green ammonia as one of three “super-leverage points” that “could trigger a cascade of tipping points for zero-carbon solutions in sectors covering 70% of global greenhouse gas emissions”. 

According to the study, Green ammonia in fertiliser production could help scale early hydrogen use for three reasons: 

1. One of the lowest ‘green premiums’ for sectors reliant on green hydrogen to decarbonise 
2. Can be shipped at a relatively low cost: allowing production in regions with rich renewable resources and able to produce hydrogen at the lowest cost globally, then transported to fertiliser production sites 
3. Ammonia is already used in fertiliser production 

A green ammonia tipping point in fertiliser could reduce green hydrogen prices, helping unlock tipping points on green ammonia use for shipping and steel production. 

As identified in the Figure 1. below, other opportunities for synergic cross-sector clean ammonia deployment exist. 

Supporting offshore wind farm operations

Renewable energy is essential for the energy transition, and offshore wind farms present great potential as clean energy source. But their operation requires support from ships currently powered by fossil fuels. These operations can be decarbonised by using clean ammonia as a shipping fuel.

Transporting ammonia as an energy carrier with carbonless fuel

Eliminating fossil fuels will eliminate a lot of the necessity for this marine traffic - about 40% of shipping cargo is actually oil, coal and gas. But not all - green fuels (like hydrogen) might also need transporting. The energy transition requires carbon-free energy vectors to allow stable export of low-carbon energy from countries with non-intermittent, low-cost sources and deliver green energy to remote locations and regions. Currently, most energy transport is done by maritime shipping, also powered by fossil fuels. Clean ammonia is a carbonless fuel that could decarbonise energy transport.

Ammonia in shipping operations

Using ammonia as fuel in combustion can produce NOx emissions, requiring control equipment such as Selective Catalytic Reduction (SCR). This system also involves ammonia, which should be provided from clean sources. Refrigerant use in shipping is another source of greenhouse gasses that could be eliminated by switching to ammonia when possible.

Chemical uses in the energy, fertiliser and climate sectors

Energy applications of ammonia as a direct power source also require SCR control equipment with ammonia. Another chemical application is producing amines used for carbon capture technologies considered in blue hydrogen production or blue urea production (in which carbon dioxide captured from combustion processes is bonded to ammonia instead of fossil fuel derived-CO₂). Carbon capture technologies can also used in the broader climate mitigation context, such as in Direct Air Capture (DAC). Replacing industry refrigerants is considered the top climate mitigation action by Project Drawdown. Ammonia should be investigated as a candidate for it.

Reducing the need for shipping fertiliser

The most effective way to tackle shipping emissions is to reduce shipping demand. 224 Mt of fertilisers are traded internationally [2]. Clean ammonia produced on demand and on-site would lessen the need for these operations.

Sustainable practices in agriculture

One of the potential energy sources for clean hydrogen is bioenergy. But this comes with a risk of land competition with other uses such as food production. If used responsibly, fertilisers produced with clean ammonia can reduce the land needed for bioenergy production. Regarding sustainable fertiliser use, environmental co-benefits can be derived from projects that associate agriculture with hydrogen production, such as using biowaste as a source of hydrogen (after biogas reforming). Not only does this reduce methane emissions from waste, but producing biogas is associated with biofertiliser production, which can help reduce dependence on synthetic fertilisers.

Unlocking market tipping points

Contrary to ammonia for fuel or energy vector, fertiliser is already a mature industry with growing demand. As mentioned, clean ammonia production for fertilisers could help scale early hydrogen, reducing green hydrogen prices and, in turn, helping unlock tipping points on green ammonia use for shipping and steel production.

References:

1. Systemiq, University of Exeter. The Breakthrough Effect.

2. Sharing insights elevates their impact. In: S&P Global | Global Fertiliser Market Analysis