Energy and Environment: Challenges and Achievements in Rapid Urbanization

Abstract

Nowadays, more than half of the world's population lives in urban areas. It is forecasted that another 20% will move into cities within the next 40 years, most of which will occur in developing countries. It is predicted that the urbanization ratio will increase from the present 52.5% to 70% in 2020 in China. The rapid urbanization questions the sustainability. Cities require huge quantities of energy and materials which produce large quantities of waste products, raising the problems of energy shortage, water pollution, soil pollution, and air quality deterioration.