Amortização do passivo ambiental de sistemas solares fotovoltaicos: estudo de caso no edifício CEAR-UFPB

Abstract

The increase in electricity generation through renewable sources has been a global strategy to reduce greenhouse gas (GHG) emissions from the energy generation sector, thus contributing to mitigating climate change. This study aimed to evaluate the environmental impacts of photovoltaic systems, focusing on the calculation of environmental payback time and the reduction of GHG emissions. The Life Cycle Assessment (LCA) methodology was used, which allowed for quantifying the environmental impacts throughout the life cycle of photovoltaic systems. The study was structured into three articles: the first conducted a bibliometric review of the diffusion of LCA in photovoltaic systems, highlighting the need for greater participation from Latin American and African countries in research on the topic. The second article calculated the life cycle inventory of the original photovoltaic system for a university building and quantified the GHG emissions. In the third article, an update to the photovoltaic system was proposed, using more modern modules. The results showed that, by adopting more efficient models, energy production increased by 39.40% and 106.67% in Scenario 1 (system power) and Scenario 2 (total area utilization), respectively. Additionally, the choice of more efficient modules contributed to the reduction of GHG emissions, decreasing the environmental payback time. In Scenario 0, which used the original system, GHG emissions were 182,927 kg CO2-eq, with 266,531.48 kg CO2-eq of emissions avoided, and the environmental payback time was 13 years, 3 months, and 29 days, with a total production of 2,539,126 kWh. In Scenario 1, which considered the system's power, GHG emissions were 89,406 kg CO2-eq, with 407,572.54 kg CO2-eq of emissions avoided, and the payback time was reduced to 5 years and 14 days, with a production of 3,539,646.71 kWh. In Scenario 2, which utilized the total available area, GHG emissions were 141,006 kg CO2-eq, with 593,644.25 kg CO2-eq of emissions avoided, and the payback time was 5 years, 5 months, and 13 days, with a total production of 5,247,501.79 kWh. These results highlight the potential of photovoltaic systems to mitigate the environmental impacts of electricity generation, especially when using more efficient technologies, which not only increase energy production but also significantly reduce GHG emissions and environmental payback time.