The world population is growing fast and continuously using more of the dwindling non-renewable energy resources of petroleum, coal, and natural gas. These resources are not only being rapidly exhausted, but their compounded use is severely damaging our environment and seriously jeopardizing the future sustainability of planet earth. If humans are to survive, renewable and clean sources of energy should be used on a massive scale replacing the ruinous fossil fuels. Current energy-driven world development has been chaotically progressing at the expense of environmental sustainability. TerraGreen12 aims at providing a milieu for experts and researchers to share their knowledge and expertise in the fields of clean and renewable energy and come up with working solutions toward a cleaner and greener planet earth.