We can build new cities but we cannot replace the environment that is vital for mans sustenance. Green energy is necessary to sustain the environment, mans health, and our ability to survive. Meet the city of Suzhou, China and the choking pollution that its population must breathe every day. It often becomes dark before the sun meets the horizon because the pollution is so dense. There is no escape. Air filters and masks must be changed frequently, your hair and clothing are quickly contaminated, and long term health impact is inevitable.