Energetica India Magazine - September 2022

energetica INDIA- September_2022 67 HYDROGEN newables. However, it must not detract from the availability of electricity for other essential and more effective uses – it must be additional. The transition to green hydrogen and the acceleration of renewable energy generation must work together. Hydrogen could also play a useful com- plimentary role to current energy stor- age solutions. Batteries are a cost-effec- tive way to store energy on a daily or potentially weekly basis but because curtailment is usually seasonal, it will never be cost effective to store 6-month worth of energy in the batteries, at least the ones we know exist of today. If re- newable energy is going to replace fos- sil fuels, we will need seasonal or even annual storage as well as international trade of renewable energy. Green mole- cules are perfect for this. Green ammonia as a key enabler of the hydrogen revolution While most of the hydrogen produced will be fed into existing pipelines and traded regionally, some regions such as Latin America, the Middle East and Northern Africa have the potential to produce more clean hydrogen than needed. Other regions such as Japan, Korea or Hawaii will have insufficient renewable sources and will need to im- port hydrogen. But transporting hydrogen over long distance is not efficient and does make much economic sense. the transpor- tation of hydrogen in large quantities from one continent to another would require a whole new liquefaction and distribution infrastructure of ports, ter- minals and storage. This is where am- monia provides a competitive solution. A recent report published by IRENA estimates that over half of the global trade in hydrogen will be in the form of ammonia. This is because hydrogen is liquified at -252°C. It is extremely reactive, requiring specific corrosion re - sistant materials which makes storage and transportation excessively expen- sive. Ammonia on the other hand can be condensed to liquid at -33°C, making it much easier to store and transport. The infrastructure already exists, with ter- minals at 120 ports around the world. Moreover, the process technology to condense hydrogen and transform it into ammonia, has a very high efficien - cy rate. Installing ammonia crackers alongside centers of green hydrogen production and consumption will sup- port the development of a hydrogen fuel economy. These crackers are still not commonly available, but their theoret- ical efficiency is high. Efforts should be made to develop them quickly at scale. Energy storage is another benefit, the relevance of which has been highlighted in the energy crisis caused by the war in Ukraine. Ammonia can be stored for as long as necessary, providing an import- ant reserve of energy security. Cheap large storage tanks remove the need to have production and consumption closely aligned. Continued Research & development open up additional uses for ammonia. On top to its role as a hydrogen carri- er, ammonia can also be used as a fuel, especially for shipping. Although it is less flammable, the energy density of ammonia is 1.5 times higher than liq - uid hydrogen. Collaborative efforts are underway to develop safe, reliable and environmentally friendly marine engine technology. A European consortium aims to have a zero-emissions vessel running on ammonia fuel by 2025. Power generation offers another appli- cation, where ammonia could be used as a fuel to replace coal, heavy fuel oil or diesel. Admittedly, this is not the most efficient way to use ammonia and hy - drogen. The only valid reason we would do this is to accelerate the adoption of green hydrogen and take advantage of existing infrastructure. Japan is looking to develop a co-firing coal and ammonia fired power plant. Direct ammonia tur - bines using hydrogen as an accelerant to improve firing are currently under development. Ammonia turbines could provide a more cost-effective net-zero alternative to carbon capture or battery storage, especially for nations which currently operate diesel turbines. Re- search in this field, to resolve the issue of NOx emissions, needs to be rapidly ramped up. And finally, green ammonia can be used as a building block to produce other chemicals including fossil free fertilizers. Various projects are underway which consider alternative ways of combining carbon and hydrogen to build plastics. These could involve carbon capture and utilization to produce hydrocarbons rather than releasing CO2 into the at - mosphere. Green Ammonia can be a cornerstone of a net zero future Green Ammonia’s role in the energy transition is going to be huge. In sum- mary, renewable energy, hydrogen and ammonia will all work together as we transition away from fossil fuels to meet our net zero targets. But capacity needs to be massively scaled-up to reduce costs and be more competitive. Once this is achieved, ammonia becomes the global renewable energy commodity, with the flexibility to be used as an energy car - rier, as a fuel and as a building block for other chemicals. Just like crude oil today.