Water and Energy - Threats and Opportunities creates an awareness of the important couplings between water and energy. It shows how energy is used in all the various water cycle operations and demonstrates how water is used - and misused - in all kinds of energy production and generation. Population increase, climate change and an increasing competition between food and fuel production create enormous pressures on both water and energy availability. Since there is no replacement for water, water security looks more crucial than energy security. This is true not only in developing countries but also in the most advanced countries. The western parts of the USA suffer from water scarcity that provides a real security threat. 
The book does not aim to show "how to design" or to solve some of the very intricate conflicts between water and energy. Instead it systematically lists ideas, possibilities and a number of results. There are a few more technical chapters that act as entry points to more detailed technical literature. Part One of the book describes the water-energy nexus, the conflicts and competitions and the couplings between water security, energy security, and food security. Part Two captures how climate change, population increase and the growing food demand will have major impact on water availability in many countries in the world. Part Three describes water for energy and how energy production and conversion depend on water availability. As a consequence, all planning has to take both water and energy into consideration. The environmental (including water) consequences of oil and coal exploration and refining are huge, in North America as well as in the rest of the world. Furthermore, oil leak accidents have hit America, Africa, Europe as well as Asia. The consequences of hydropower are discussed and the competition between hydropower generation, flood control and water storage is illustrated. The importance of water for cooling thermal power plants is described, as this was so tragically demonstrated at the Fukushima nuclear plants in 2011. Climate change will further emphasize the strong coupling between water availability and the operation of power plants. Part Four analyses energy for water - how water production and treatment depend on energy. The book shows that a lot can be done to improve equipment, develop processes and apply advanced monitoring and control to save energy for water operations. Significant amounts of energy can be saved by better pumping, the reduction of leakages, controlled aeration in biological wastewater treatment, more efficient biogas production, and by improved desalination processes. The water-energy issue is not only about technology. It is our attitudes and our lifestyle that can significantly influence the consumption of both water and energy. We all have to be reminded that water is energy and energy is water.
The book is aimed at various kinds of readers: The politician and decision maker - providing a holistic view; The engineer who wishes to find out about the key issues and to understand the strong driving forces from the increasing population, climate change and the food supply in the world; The student who wishes to get an overview of future challenges and new possibilities; The planner - water and energy have to be planned together; The designer of a water and wastewater system - how does energy come in? The operator of a water or a wastewater treatment plant - what are the possibilities to make the system more efficient; The wastewater treatment manager - what are the possibilities to save and recover energy in a wastewater treatment plant; The researcher – looking for connections between different specialities....