Renewable energy source (RES) based electrical power plants are widely considered green and clean due to their contribution to decarbonizing the energy sectors. It is apparent that RESs do not produce carbon dioxide, however their significant negative impacts on the environment are still found and cannot be ignored. In this paper, the environmental impacts of RES based power plants are analyzed through a comprehensive review considering solar thermal, solar photovoltaic, wind, biomass, geothermal, hydroelectric, tidal, ocean current, oceanic wave, ocean thermal, and osmotic effects. Solar thermal power is well known as concentrated solar power. A strength, weakness, opportunity, and threat (SWOT) analysis is carried out and discussed for all RES based power plants. Comparative SWOT analyses for solar photovoltaic and concentrated solar power plants are presented. The comparative environmental impact analyses for all existing RES based power plants are tabulated for various attributes. These attributes include but are not limited to human health, noise, pollution, greenhouse gas emission, ozone layer depletion, toxification, flooding, impact on inhabitants, eutrophication, dried up rivers, and deforestation. Based on the analysis, it is found that careful selection of RES for electrical power plants is necessary because improper utilization of RES could be very harmful for the environment.