Environmental life cycle-based analysis of fixed and single-axis tracking systems for photovoltaic power plants: A case study in Brazil

Replacing fossil fuels with solar photovoltaics (PV) has proven to be a viable option for transitioning the global economy to a low-carbon future. However, although the power generation from solar PV systems is often considered carbon-free by society, they have several potential adverse effects on the environment during different stages of their value chain. Furthermore, various factors significantly affect electricity generation through solar PV modules, such as their orientation angle relative to the sun. In this context, this paper aims to assess the environmental impacts of fixed and single-axis tracking systems (SATS) from a solar PV power plant composed of multi-crystalline silicon (multi-Si) PV modules in Northeast Brazil. For this purpose, our analysis explores their environmental performance against global warming, land use, and water consumption from a life cycle perspective. It includes the production of solar PV modules, transport activities, and the construction, operation, maintenance, and end-of-life of the solar PV power plant, using the Ecoinvent database and the ReCiPe 2016 method. According to our results, the most environmentally sound option is the solar PV system using SATS since it is, on average, 17% less impactful in all three impact categories considered than the other solar PV system installed on fixed structures. Hence, prioritizing SATS on the current solar PV generation expansion in Brazil can reduce GHG emissions, land use, and water consumption by up to 17%, 15%, and 7%, respectively. Furthermore, minor changes not exceeding 1.5% were observed by analyzing the nationalization of the solar PV modules, reducing GHG emissions and land use, and increasing water consumption.