This special issue contains original research articles on solar energy use for green applications. In particular, the use of solar thermal energy for low environmental impact processes or the use of the light (with or without heterogeneous photocatalysts) for environmental remediation or synthesis was considered. The topic is highly challenging and the subject would be important, timely, and of great interest. Among the submitted manuscripts, 5 were selected as suitable for publication through the strict experts’ peer reviews.

The papers to be published in this special issue are “Design and Performance Evaluation of a Solar Assisted Heat Pump Dryer Integrated with Biomass Furnace for Red Chilli” for the direct solar light/thermal applications; “Sorbents Coupled to Solar Light TiO2-Based Photocatalysts for Olive Mill Wastewater Treatment,” “Photodegradation of 2,4-Dichlorophenol in Aqueous Systems under Simulated and Natural Sunlight,” and “Flexible Bench-Scale Recirculating Flow CPC Photoreactor for Solar Photocatalytic Degradation of Methylene Blue Using Removable TiO2 Immobilized on PET Sheets” for the photodegradation topic; and “Noble Metal Decoration and Presulfation on TiO2: Increased Photocatalytic Activity and Efficient Esterification of n-Butanol with Citric Acid” for synthetic photochemistry.

We believe that this special issue can be interesting and inspiring for the readers of the journal since this advanced interdisciplinary technology involves a wide range of subjects.

Daniele Dondi
Sandra Babić
Irene Michael
Giovanni Palmisano
Andrea Speltini