Agustin Valera-Medina is a Reader/Associate Professor at Cardiff School of Engineering, U.K. He has a bachelor’s degree in Mechanical Engineering from UNAM, Mexico, and an MSc and a PhD in the field of Energy from Cardiff University, U.K. He has participated as PI/Co-I in 27 industrial projects with multinationals including PEMEX, Rolls-Royce, Siemens, Ricardo, Airbus, and BP, attracting approximately £8.5M in research. He has published 162 papers (h-index 22), 30 of these specifically concerning ammonia power. He has supervised 25 PhD students, 7 on ammonia-related topics. Dr. Valera-Medina led Cardiff’s contribution to the Innovate-UK “Decoupled Green Energy” Project (2015–2018) led by Siemens and in partnership with STFC and the University of Oxford, which aimed to demonstrate the use of green ammonia produced from wind energy. He is currently PI of the project SAFE-AGT (EP/T009314/1, £1.9M) to demonstrate the use of ammonia as an efficient gas turbine fuel. He leads the combustion work package of the H2020 project FLEXnCONFU (884157), a €12.7M project conceived to demonstrate ammonia power in large turbine engines. He is also PI and co-I of projects related to ammonia for transportation, propulsion, and heat/cooling. He has been part of various scientific boards, chairing sessions in international conferences and moderating large industrial panels on the topic of “Ammonia for Direct Use.” He supported the preparation of the Royal Society Policy Briefings “Green Ammonia” on the use of ammonia as energy vector. He is main author of the book 'Techno-economic challenges of ammonia as energy vector' (Elsevier).

Abstract

Ammonia-Blends for Gas Turbines

A hydrogen economy has been the focus of researchers and developers over the decades. However, the complexity of moving and storing hydrogen has always been a major obstacle to deploy the concept. Therefore, other materials can be employed to improve handling whilst reducing cost over long distances and long periods. Ammonia, a highly hydrogenated molecule, can be used to store and distribute hydrogen easily, as the molecule has been employed for more than 150 years for fertilizer purposes. Being a carbon-free chemical, ammonia (NH3) has the potential to support a hydrogen transition thus decarbonising transport, power and industries. However, the complexity of using ammonia for power generation lays on the appropriate use of the chemical to reach high power outputs combined with currently low efficiencies that bring up overall costs. This complex scenario is also linked to the production of combustion profiles that tend to be highly polluting (with high NOx emissions and slipped unburned ammonia). There is no technology capable of using ammonia whilst producing both low emissions and high efficiencies in large power generation devices, thus efficiently enabling the recovery of hydrogen and reconversion of stranded, green energy that can be fed back to the grid. Tackling these problems can resolve one of the most important barriers in the use of such a molecule and storage of renewable energies. Therefore, this seminar presents state-of-the-art global research that has taken place to understand the combustion features of ammonia blends whilst addressing their application at medium and large power scales. The complexity of nitrogen bounding and its reactivity are discussed with emphasis to tackle NOx emissions. Finally, risks, health and safety, and public perception implications are also presented to provide guidelines for the implementation of facilities to evaluate ammonia for combustion purposes.