This book emerges from the recognition that energy, environment and ecosystems are dynamically and inextricably connected. The energy environment system must be addressed in its totality, so that we can devise sustainable solutions that incorporate both economic growth and environmental conservation. No single clean energy source will sustain long-term energy security, and fossil fuels will remain prominent in the mix of energy sources for several decades to come. Energy solutions, therefore, must employ a broad and diverse range of approaches, including cleaner fossil fuel technologies, and an affordable transition to greener power generation employing waste, water and renewable resources. Moreover, adapting to this changing global energy picture will require a transformational shift in the ways we use and deliver energy services. The authors begin with a broad introductory chapter on sustainable energy and the environment, classifying energy resources, cataloging environmental degradations, and outlining the concepts and practices of sustainability. In Chapters Two and Three, they summarize the basic constituents of the environment, the biosphere and its natural cycles, and offer a model of Earths planetary temperatures and the greenhouse effect. Chapters Four and Five outline conventional energy and power systems, and related environmental degradations. The next several chapters cover clean coal technologies for power generation, and discuss sustainable energy and power technologies based on both thermal and photovoltaic solar energy, along with biomass and wind. The final chapters examine in depth the management of waste and water, pollution control and energy conservation. The book introduces a unique approach to sustainability and energy conservation which emphasizes the relationships between underlying scientific principles and practical applications employed in engineering solutions. All this is offered in a form that matches the requirements of college-level environmental science and engineering courses. N.D. Kaushika, formerly professor, Centre for Energy Studies, Indian Institute of Technology Delhi, subsequently director of reputed engineering institutions in Delhi and National Capital Region, is a specialist in renewable energy and environment. He is recipient of S.S. Bhatnagar Research Endowment Award (Hariom Ashram Prerit) for research in Energy Conservation in 1987. Presently consultant at Innovation Centre, Ansal University, Gurgaon. Has earlier been author of two books and has contributed articles in several reputed journals and authored chapters in books by international publishers including Academic Press, USA and Elsevier Science major reference work. K.S. Reddy, Professor of Mechanical Engineering at IIT Madras, Chennai is specialist in solar energy, energy efficiency and environment. Presently, he is also honorary professor at University of Exeter, U.K. and Adjunct Professor, CEERI-CSIR. He has authored more than 150 research papers in reputed international journals and conferences. Dr. Reddy has executed several research projects on solar energy sponsored by various national and international agencies. He is actively involved in development of Concentrating Solar Power technologies in India. He has filed couple of patents on solar CPV and CSP systems. He is associated with several industries on power generation, process heat, energy efficiency & conservation and characterization of engineering materials. He has also organized several national and international workshops on advanced renewable energy technologies at IIT Madras. Kshitij Kaushik, Associate Vice President in Sky Power in Canada is specialized in energy efficiency and solar photovoltaic. He is co-author in one book and has contributed research articles in reputed international journals.