Onshore wind power has immense potential to accelerate South Africa’s energy transition to a sustainable power mix, effectively addressing the rising demand for electricity and mitigating the adverse impacts of fossil fuels. However, the effects on human health, crops, biodiversity, and materials caused by the technology remain largely unexplored in the existing literature. This study addresses this gap by examining both the greenhouse gas (GHG) and non-GHG emissions, as well as the external costs associated with onshore wind power in South Africa. Specifically, we focus on the 138 MW Jeffreys Bay Wind Farm, analysing its entire life cycle from material extraction/manufacturing (M), transportation (T), operation and maintenance (O&M), to decommissioning and disposal (D). This approach, known as life cycle assessment (LCA), provides a comprehensive understanding of the environmental impact. Results show that GHG impact accounts for 26.062 gCO2 eq/kWh and human health is the most significant non-GHG impact at 0.638 g/kWh.