ANALYZING THE ENVIRONMENTAL IMPACT OF RENEWABLE ENERGY SOURCES: A COMPARATIVE STUDY OF SOLAR, WIND, AND HYDROPOWER

Abstract

The global transition from fossil fuels to renewable energy is essential for mitigating climate change, but it necessitates a comprehensive understanding of the environmental trade-offs associated with different renewable technologies. This study provides a quantitative comparative analysis of the lifecycle environmental impacts of three dominant renewable energy sources: solar photovoltaic (PV), wind, and hydropower. Employing a problem-based research methodology, the analysis integrates lifecycle assessment (LCA) data, land-use metrics, material intensity, and ecosystem impact indicators from over 150 global projects commissioned between 2010 and 2023. Results indicate that while all three sources offer substantial carbon emission reductions (92-99%) compared to conventional coal, their environmental footprints differ markedly across impact categories. Hydropower exhibits the lowest median greenhouse gas (GHG) emissions at 12 g CO₂-eq/kWh but has the most significant ecosystem disruption and land-use change impacts. Utility-scale solar PV has a higher median carbon intensity (42 g CO₂-eq/kWh), primarily due to manufacturing, but demonstrates lower ecosystem impact per unit of energy generated. Wind power, particularly onshore, shows a favorable balance with a median GHG emission of 15 g CO₂-eq/kWh and moderate land use, though it poses notable challenges for avian and bat populations. The study identifies critical problem areas, including the mineral resource scarcity for solar PV, the biodiversity loss associated with large hydropower reservoirs, and the end-of-life management of composite materials for wind turbines. The findings underscore that there is no single "lowest-impact" source; optimal deployment depends on localized environmental constraints and the specific impact category prioritized. This research concludes that a diversified, spatially optimized renewable energy portfolio, informed by robust local and global environmental impact assessments, is crucial for a sustainable energy transition that genuinely minimizes ecological harm.