Ecological solar absorber coating: A proposal for the use of residual biomass and recycled materials for energy conversion

• Published in: Solar energy Vol. 202; pp. 238 - 248
• Main Authors: López-Sosa, Luis Bernardo, González-Avilés, Mauricio, Hernández-Ramírez, Luis Mariano, Medina-Flores, Ariosto, López-Luke, Tzarara, Bravo-Sánchez, Mariela, Zárate-Medina, Juan
• Format: Journal Article
• Language: English
• Published: New York Elsevier Ltd 15-05-2020; Pergamon Press Inc
• Subjects: Absorption; Biomass; Biomass energy production; Carbon; Coatings; Cookers; Cooking; Ecological coating; Economic impact; Energy; Energy absorption; Energy conversion; Environmental impact; Evaluation; Forest biomass; Grapefruit; Impact analysis; Infrared spectroscopy; Operating temperature; Optical properties; Parameter identification; Photothermal conversion; Polystyrene; Polystyrene resins; Raman spectroscopy; Recycled materials; Solar absorber; Solar cookers; Solar energy; Solar energy absorbers; Solid wastes; Soot; Substrates; Technology; Thermal conductivity; Thermodynamic properties; Thermosolar technology; Waste materials; Ecological coating; Thermosolar technology; Solar absorber
• ISSN: 0038-092X; 1471-1257
• DOI: 10.1016/j.solener.2020.03.102

•A low cost, low environmental impact and easy to make solar absorber coating was developed.•The coating is highly absorbent in the solar spectrum.•The structural characterization of the functional material of the solar absorbent coating was performed.•The optical and thermal properties of the solar absorber coating were estimated.•The coating was evaluated in a solar cooker, generating better results than conventional paints.
This paper discusses the development of a coating made of solid waste and residual biomass and its application as ecological solar absorber coating. This absorbent solar coating is made with a binder that consists of essential grapefruit rind oil and expanded polystyrene, both obtained from waste materials, as well as forest biomass soot (FBS) processed by mechanical grinding and used as a functional photothermal material. This mixture produces a paint that can be applied to metallic substrates to form a solar energy-absorbing surface. The characterization and evaluation is shown in three steps: (a) Characterization of the materials using XRD, SEM, TEM, XPS, Raman spectroscopy and IR; (b) coating evaluation using AFM, optical characterization to measure solar absorption, TG to determine the operating temperature and laser flash analysis to determine thermal conductivity; and (c) a testing with thermosolar technology to determine the thermal parameters of solar cookers. It has been identified that the pseudo-amorphous carbon in FBS has solar energy absorption capacity due to the sp2-sp3 bonds present in this kind of carbon, associated with the material’s graphitic domain. Also, results show that the coating can be used with thermosolar technologies operating above 250 °C with a solar absorption index above 96%, and it has thermally-efficient properties. In addition, the coating, it shows better results with solar cookers than other coatings used with this technology, increasing cooking power, so it can potentially be employed with various thermosolar technologies due to the replicability of its materials, its low environmental impact and low economic cost.