Why ammonia is the more efficient hydrogen carrier

Our demand for hydrogen is growing from year to year. In 2050, the demand for hydrogen will be seven times higher than the market demand for hydrogen in 2020. To ensure that we can meet the demand in Germany, we depend on importing green hydrogen. Since the transport of hydrogen, also called liquid H₂, is very complex, lossy, and expensive, one chemical compound is a particularly important energy carrier for the energy transition: ammonia (NH₃).

Ammonia - an ideal hydrogen storage medium and energy carrier

The use of ammonia as an energy carrier and means of transporting hydrogen has many advantages. Firstly, it is more energy-efficient to transport than hydrogen. Secondly, ammonia can be used to transport larger amounts of energy over long distances in less space. Thirdly, we already have a globally established infrastructure for transporting ammonia that is safe and efficient.

To produce green ammonia, hydrogen is produced by electrolysis from 100% renewable sources and combined with nitrogen extracted from ambient air using an air separator. This is a carbon-free process that produces a climate-neutral energy carrier. The green ammonia produced can now be transported to its destination by ship. Ships and port terminals for this are already in place worldwide.

Once the ammonia arrives at its destination, it is split back into hydrogen and nitrogen using the ammonia cracking process. The hydrogen can then be used in numerous industries as a climate-neutral energy carrier. The thyssenkrupp Uhde team uses the uhde® reformer technology as the basis for large-scale ammonia cracking.

The ammonia cracking process: heating, splitting, cooling, purification

To decompose ammonia to hydrogen and nitrogen_, an ammonia cracker is used. First, the ammonia is heated until it evaporates into a gaseous state. It is then fed into the reactor, where ammonia splitting takes place catalytically. Usually, the process runs at temperatures of 600-900 °C and a pressure of 20-40 bar. The product is then cooled and the residual by-products are separated out to obtain a pure hydrogen stream. This can then be used directly or fed into a pipeline. Industrial applications can be found, for example, in the steel industry, in the chemical industry or as fuel for fuel cells.

The key role of ammonia in the energy transition

thyssenkrupp Uhde supplies technologies for the construction of plants for the production, loading, unloading and storage of green ammonia as well as the technology for hydrogen recovery. By scaling up and commercially developing ammonia cracking plants, the team will enable the establishment of global value chains for green hydrogen in order to use ammonia optimally as an energy carrier.