Renewable electricity generation technologies provide a more sustainable solution than the non-renewables. However, as a complete system, renewable energy generation systems have some overall environmental impacts on humankind, resources and ecosystems. This paper will address the environmental effects caused by different types of renewable plants through life-cycle assessment. A comparative study is done among solar PV, biomass, and pumped storage hydropower plants in the United States. Life-cycle impact analysis has been carried out by the Eco-indicator 99, TRACI (Tool for the Reduction and Assessment of Chemical and other Environmental Impacts), CED (Cumulative Energy Demand), Ecopoints 97, RMF (Raw Material Flows) and IPCC (Intergovernmental Panel on Climate Change) methods, using the SimaPro software. The impacts are considered in 10 mid-point impact categories and three end-point indicators. The results show that pumped storage hydropower plants have the highest impact on human health (7.74E-05/kWh) and the ecosystem (3.35E-06/kWh), whereas biomass plants have the maximum effect on resources (4.79E-07/kWh). Overall, the solar PV plants are found to be much more environment-friendly than other renewable electricity generation systems. These findings will guide investors in installing sustainable and clean power plants. (C) 2019 Elsevier Ltd. All rights reserved.