Life Cycle and Environmental Impact Assessment of Sustainable Energy Systems in Building Construction: Comparative Analysis of Fossil Fuels and Solar Energy in Mashhad

Abstract

Rapid urbanization and the growing demand for sustainable development have emphasized the need to transition from fossil fuels to renewable energy sources in the construction sector. This study presents a comprehensive Life Cycle Assessment (LCA) and Environmental Impact Assessment (EIA) to compare the carbon footprints of fossil fuel-based and solar energy systems in residential buildings in Mashhad, Iran. Results from Revit simulations and MATLAB modeling based on Leopold matrix highlight the significant advantages of solar energy, with life cycle CO₂ emissions peaking at only 2.5 kg in the most emission-intensive months, compared to 120 kg for fossil fuels during electricity generation in July. Furthermore, the annual cumulative emissions of fossil fuels reached nearly 1800 kg CO₂, whereas solar energy remained under 100 kg CO₂. These findings show the critical role of solar energy in achieving sustainability. The research offers actionable insights for reducing greenhouse gas emissions and advancing green engineering practices by addressing the seasonal and lifecycle phases of energy systems.