energies Review A Comprehensive Review on the Recent Development of Ammonia as a Renewable Energy Carrier Muhammad Heikal Hasan 1,* , Teuku Meurah Indra Mahlia 1,* , M. Mofijur 1, I.M. Rizwanul Fattah 1 , Fitri Handayani 2, Hwai Chyuan Ong 1 and A. S. Silitonga 3 1 Centre for Green Technology, Faculty of Engineering and IT, University of Technology Sydney, Sydney, NSW 2007, Australia; MdMofi
[email protected] (M.M.);
[email protected] (I.M.R.F.);
[email protected] (H.C.O.) 2 Department of Mechanical Engineering, Syiah Kuala University, Banda Aceh 23111, Indonesia; fi
[email protected] 3 Department of Mechanical Engineering, Politeknik Negeri Medan, Medan 20155, Indonesia;
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[email protected] (T.M.I.M.); Tel.: +61-4123-08541 (M.H.H.); +61-2951-490571 (T.M.I.M.) Abstract: Global energy sources are being transformed from hydrocarbon-based energy sources to renewable and carbon-free energy sources such as wind, solar and hydrogen. The biggest challenge with hydrogen as a renewable energy carrier is the storage and delivery system’s complexity. There- fore, other media such as ammonia for indirect storage are now being considered. Research has shown that at reasonable pressures, ammonia is easily contained as a liquid. In this form, energy density is approximately half of that of gasoline and ten times more than batteries. Ammonia can provide effective storage of renewable energy through its existing storage and distribution network. Citation: Hasan, M.H.; Mahlia, In this article, we aimed to analyse the previous studies and the current research on the prepara- T.M.I.; Mofijur, M.; Rizwanul Fattah, tion of ammonia as a next-generation renewable energy carrier.