Ammonia has the potential to contribute significantly to the decarbonisation of energy systems, by offering a practical, carbon-free hydrogen storage and transportation vector as well as a green fuel in its own right. To better understand the prospects and challenges surrounding the use of ammonia in energy systems, Siemens is leading a collaborative project to build and test an ammonia-based energy storage system at the Rutherford Appleton Laboratory in the UK. Together with its project partners (the UK Science and Technology Facilities Council, the University of Oxford and the University of Cardiff), and supported by Innovate UK, Siemens will demonstrate the full energy cycle of renewable power converted into ammonia and then back into electricity for grid export.
Here, a wind turbine is used as the renewable energy source, a PSA air-separation unit provides the nitrogen, and hydrogen is obtained from a PEM electrolyser. The ammonia is synthesised using the traditional Haber-Bosch process, in a purpose-built reactor loop, before being stored locally in a tank. The energy-release step is accomplished by fuelling a spark-ignition ICE generator set with the “green” ammonia. The nominal power of the system is 30kWe. A key project objective is showing that mature technology can be deployed in the construction of such systems, with the implication that it could be rapidly scaled up into a commercial plant. A second, but equally important objective is to provide a platform for further development work, including energy systems design, both the ammonia synthesis and energy-release processes, and future ammonia off-take markets. Finally, and perhaps most important of all, this demonstrator is timely in the context of increasing interest in carbon-free solutions to all our energy needs, and the rapidly reducing costs of both large-scale renewable power facilities and electrolysers.
This presentation will summarise the status and learning to date from the demonstrator project, which is due to be commissioned later this year. Future prospects for the use of ammonia in decarbonised energy systems, including economic considerations, will also be discussed.