The global energy system is undergoing a radical transition of decarbonisation right across the value chain. The world, in general, is pursuing low carbon solutions to power generation, mobility, industrial use and heat. One strategy that is very popular is utility-scale renewable electrification and that has great potential in some areas, but it faces several challenges.
Energy carrying molecules have for centuries served as the productive means of low-cost energy transfer. Today, increasing demand to replace carbon intensive energy is creating opportunity for molecules such as hydrogen, ammonia and methanol as replacements for the hydrocarbon alternatives.
Hydrogen is a great option as it has got the highest energy density by weight of any chemical fuel. The problem with hydrogen is that its volumetric energy density is low – it is difficult to get a lot of hydrogen in a small space.
Ammonia, a molecule that comprises one nitrogen atom and three hydrogen atoms, solves the conundrum of replacing hydrocarbon fuels with something that does not contain any carbon, while also overcoming the challenges of storing and distributing hydrogen in bulk. Moreover, there is a very established ammonia industry today.
Coupling renewable electricity production to ammonia creates the opportunities for a competitive market against electrochemical batteries, pumped hydro, and capacitors to balance consumption and renewable generation. What differentiates ammonia and other chemicals is ability to hold energy for a long period of time, which can be transported long distances at lower cost.
The world is categorically dependent on ammonia – today, half the world’s food production depends on it for increasing crop yield, resulting in a $70 billion market. However, outside of its traditional case – 80% of this ammonia is used in the fertilizer industry – renewable/decentralised production of the molecule opens up broader set of use cases.
Ammonia can be synthesised from raw materials that we have in abundance, namely water and air, using renewable energy. It has nine times the energy density of Li-ion batteries, and three times that of compressed hydrogen, creating potential as a carbon-free energy carrier. Whilst ammonia has a well-established supply chain, the “Green Ammonia” market is only just starting to gain traction globally.
There have been a lot of studies carried out on our future energy system and while these are useful and informative, there comes a time when you have to start building and testing systems in order to learn about the real-world issues in deploying them – and for ammonia as a green energy vector I believe that time is now.
KEY APPLICATIONS IN THE MARKET
MARITIME TRANSPORT FUEL. Driven by emissions reduction targets set by the International Maritime Organisation in January 2020, ammonia is being considered as an alternative to bunker fuel. Widespread commercial adoption is predicted by DNV GL to begin in 2037. Ammonia is estimated to represent ~25% of the maritime fuel mix by 2050. Mechanical engineering giant MAN is planning to develop an ammonia-fuelled two-stroke engine for the marine market.
INDUSTRIAL ENERGY SOURCE. The generation of heat for industrial processes accounts for 10% of global greenhouse gas emission. Similar to hydrogen, ammonia is being considered for its potential to directly power combustion without any carbon emissions.
RENEWABLE ENERGY EXPORT. The Green Ammonia Consortium in Japan estimates that demand for direct use of green ammonia will reach 1.7 million tonnes per annum by 2030.
