*Editorial* **Special Issue "Thermochemical Conversion Processes for Solid Fuels and Renewable Energies"**

**Falah Alobaid \* and Jochen Ströhle**

> Institute for Energy Systems and Technology, Technical University of Darmstadt, Otto-Berndt-Straße 2, 64287 Darmstadt, Germany; jochen.stroehle@est.tu-darmstadt.de

**\*** Correspondence: falah.alobaid@est.tu-darmstadt.de; Tel.: +49-(0)-6151-16-23004

**Abstract:** The world society ratifies international measures to reach a flexible and low-carbon energy economy, attenuating climate change and its devastating environmental consequences. The main contribution of this Special Issue is related to thermochemical conversion technologies of solid fuels (e.g., biomass, refuse-derived fuel, and sewage sludge), in particular via combustion and gasification. Here, the recent activities on operational flexibility of co-combustion of biomass and lignite, carbon capture methods, solar-driven air-conditioning systems, integrated solar combined cycle power plants, and advanced gasification systems, such as the sorption-enhanced gasification and the chemical looping gasification, are shown.

**Keywords:** thermochemical conversion technologies; combustion; carbon capture and storage/utilization; gasification; solar-driven air-conditioning; integrated solar combined cycle; energy and exergy analyses; thermodynamic modeling; dynamic process simulation

**Citation:** Alobaid, F.; Ströhle, J. Special Issue "Thermochemical Conversion Processes for Solid Fuels and Renewable Energies". *Appl. Sci.* **2021**, *11*, 1907. https://doi.org/ 10.3390/app11041907

Academic Editor: Frede Blaabjerg

Received: 10 February 2021 Accepted: 17 February 2021 Published: 22 February 2021

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