In this study, we present a comparative environmental impact assessment of renewables and conventional fossil fuels for electricity and hydrogen generation. The conventional fossil fuels investigated in this study are coal, oil, and natural gas. Renewables considered in this study are geothermal, hydropower, ocean, solar, and wind energies. Furthermore, nuclear and biomass energies are taken into consideration while assessing environmental impact and performances. Environmental impact criteria considered in this study are CO2, NOx, and SO2 emissions, land use, water consumption, water quality of discharge, solid waste and ground contamination, and biodiversity. For comparison purposes, all collected data are normalised and ranked between 0 and 3 while 0 giving highest negative environmental impact and 3 giving lowest negative environmental impact. Our results showed that overall, in terms of both electricity and hydrogen production, oceans give the highest rankings (2.71 for electricity and 2.73 for hydrogen). Coal has the lowest rankings in terms of environmental impact (0.26 for electricity and 0.30 for hydrogen).
- Global warming