Decarbonisation Technology - February 2024 Issue

electricity and heat in fuel cells. The combustion of hydrogen is clean, with water as the only product of combustion. It is twice as efficient as combustion engines powered by e-fuels. However, we lack a hydrogen infrastructure, and at present hydrogen is difficult for long- range transport. As an alternative to ammonia, methanation of green hydrogen results in synthetic natural gas (SNG), which is composed of pure clean CH 4 gas without any residual unwanted substances. Also, hydrogen-to-liquid technologies convert green hydrogen to e-fuels. Both SNG and e-fuels can be used in existing transport applications, which may be advantageous in the near term.  Renewable ammonia : Ammonia is relatively easy to handle and store as it can be liquefied under low/modest pressure (10 to 15 bar) or refrigerated at -33°C temperature. Ammonia is an ideal chemical store for renewable energy. The existing distribution network, in which ammonia is stored in large, refrigerated tanks and transported around the world by pipes, road tankers and ships, can be readily used. Green or renewable ammonia is a zero-carbon fuel that can be used directly in the chemical industry and carbon neutral fertiliser products. It can be burnt in an engine or used in a fuel cell to produce electricity, with byproducts such as water and nitrogen. The maritime industry is likely to be an early adopter, replacing the use of fuel oil in marine engines. Ammonia is also an effective hydrogen carrier as it is not only easier to store and transport, but also can be easily cracked and purified to release hydrogen when required. In short, switching to renewable electricity to make renewable ammonia could save more than 360 million tons of CO 2 worldwide, as per Future Market Insights analyst (FMI, 2023). It can also be converted back into hydrogen or combusted to generate electricity when the wind is not blowing or solar power is not effective.  Methanol : There is an emerging market for green methanol today, and demand is expected to increase due to developing applications in the marine, biofuels, and chemicals markets. We see the marine and biofuels market developing

at a healthy pace mainly due to their promise as solutions to reduce CO 2 emissions. Shipping companies, like Maersk, have successfully proven that methanol is a viable fuel. The hard-to-abate industries such as steel, cement, and chemicals can also decarbonise by producing renewable methanol from CO 2 emissions captured at their facilities (Raman, 2023). It can be seen from the above that for all three renewable (green) products, hydrogen, ammonia, and methanol, their growth is not limited by the technology to produce them, but rather by their “ There is an emerging market for green methanol, and demand is expected to increase due to developing applications in the marine, biofuels, and chemicals markets ” cost compared to their fossil (grey) counterparts. Also, green ammonia and methanol are ideal chemical forms of renewable energy storage that can compensate for the intermittent nature of renewable electricity sources like wind and solar. Besides, ammonia is carbon-free, making it an easily dispatchable hydrogen carrier that enables cost-effective storage and distribution of a large amount of renewable energy. Conclusion The circular economy is driving changes to meet the new requirements. The feed used to produce the fuel determines how it fits into the circular economy and within the carbon lifecycle. The development of the different feeds and implementation into commercial practice is underway. The final resolution is yet to be seen.

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Scott Sayles ssayles@becht.com Robert Ohmes rohmes@becht.com

Pattabhi Raman Narayanan pnarayanan@becht.com

Jessica Hofmann jhofmann@becht.com