*Editorial* **Energy for Sustainable Future**

**T. M. Indra Mahlia \* and I. M. Rizwanul Fattah \***

Centre for Green Technology, Faculty of Engineering and I.T., University of Technology Sydney, Ultimo, NSW 2007, Australia

**\*** Correspondence: TMIndra.Mahlia@uts.edu.au (T.M.I.M.); IslamMdRizwanul.Fattah@uts.edu.au (I.M.R.F.)

Energy and the environment are interrelated, and they are critical factors that influence the development of societies. The pollution of the environment, without considering various consequences, has become one of the most important global issues today. This environmental pollution is mainly the result of increases in economic activities, population, transportation, electricity generation, agriculture, forestry, and land use. The exigency of energy for these activities, the rapidly rising price of petroleum oil, the harmful effect of greenhouse gases, and the quest for energy security have steered our attention towards sustainable sources of energy. It is fundamental to find innovative solutions that are sustainable from the perspective of energy management and environmental protection. These solutions will provide a promising future in terms of energy sources meeting energy demand, together with maintaining the environment.

This book includes three review articles, which review the state-of-the-art of different sustainable energy resources. These articles include ammonia as a renewable energy carrier [1], integration of solar photovoltaic [2], and bio-oil from waste tires for automotive engine applications [3]. In addition, eight research studies reveal new knowledge about energy for a sustainable future. The topics covered span many diverse areas associated with sustainable energy, including various biofuels [4,5], photovoltaic [6], and other aspects of sustainability [7–11]. These complementary contributions provide a substantial body of knowledge in the field of renewable and sustainable energy.

We would like to thank the academic and managing editors, as well as the reviewers, for their efforts and input. We enjoyed editing the papers for this collection.

**Author Contributions:** Writing—original draft preparation, I.M.R.F.; writing—review and editing, T.M.I.M.; supervision, T.M.I.M. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Conflicts of Interest:** The author declares no conflict of interest.

**Citation:** Mahlia, T.M.I.; Fattah, I.M.R. Energy for Sustainable Future. *Energies* **2021**, *14*, 7962. https:// doi.org/10.3390/en14237962

Received: 22 November 2021 Accepted: 23 November 2021 Published: 29 November 2021

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