Renewable exergy return on investment (RExROI) in energy systems. The case of silicon photovoltaic panels

Torrubia, Jorge ; Valero, Alicia (Universidad de Zaragoza) ; Valero, Antonio (Universidad de Zaragoza)

Resumen: The ongoing energy transition towards renewable sources faces reliance on fossil fuels throughout their life cycle, primarily due to mining and material production for infrastructure. This study proposes the Renewable Exergy Return on Investment (RExROI) metric, which quantifies the renewable exergy obtained from each unit of non-renewable exergy invested in energy systems. It can be seen as a Renewation Index, applicable to any energy production system, indicating the degree of renewability of such technologies. Focused on silicon photovoltaic panels, the study explores five material intensities, nine scenarios based on the capacity factor and lifespan, and two alternatives for electricity used in the manufacture. Results show that material intensity increases RExROI from −0.6 MJ/MJ (non-renewable exergy is higher than electricity produced) to 5.7 MJ/MJ, increasing until 19 MJ/MJ with the best location and lifespan, and reaching 34 MJ/MJ if renewable electricity is used in manufacturing. Thus, carbon intensity can range from 734 to 7 gCO2eq/kWh. Furthermore, some strategies to enhance RExROI are discussed based on the (i) energy sources, (ii) materials, and (iii) production stages of photovoltaic panels. Thus, this study demonstrates the usefulness of RExROI in evaluating the energy-material-emission nexus of energy systems through exergy in the context of energy transition.

Idioma: Inglés

DOI: 10.1016/j.energy.2024.131961

Año: 2024

Publicado en: Energy 304 (2024), 131961 [9 pp.]
ISSN: 0360-5442

Financiación: info:eu-repo/grantAgreement/EC/HORIZON EUROPE/101091668/EU/Aragon's REgional Hub for circularity: Demonstration Of Local industrial-urban symbiosis initiatives/REDOL
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PID2020-116851RB-I00

Tipo y forma: Article (Published version)

Área (Departamento): Área Máquinas y Motores Térmi. (Dpto. Ingeniería Mecánica)