The tradeoffs between energy and water have been gaining international attention in recent years as demand for both resources mount and governments continue to struggle to ensure reliable supply to meet sectoral needs. As almost all energy generation processes require significant amounts of water, and water requires energy for treatment and transport, these two resources are inextricably linked. This relationship is the energy-water nexus.
As population and economies grow many regions of the world experience water and energy security challenges that must be addressed now. During the next 20 years, cities in developing countries will have to meet the demand of 70 million more people each year. Recent FAO estimates show that by 2050, feeding a planet of 9 billion people will require a 60 percent increase in agricultural production and a 6 percent increase in already-strained water withdrawals (FAO, 2012). Further, over 1.3 billion people worldwide still lack access to electricity; most of them reside in sub-Saharan Africa and East-Asia (IEA, 2012). About 2.8 billion people live in areas of high water stress and 1.2 billion live in areas of physical scarcity. It is estimated that by 2030, nearly half of the world’s population will be living in areas of high water stress affecting energy and food security (WWAP, 2012). According to recent estimates from the World Energy Council, emerging economies like China, India, and Brazil will double their energy consumption in the next 40 years. By 2050, Africa’s electricity generation will be seven times as high as it is today. Similarly, in Asia, primary energy production will almost double, and electricity generation will more than triple by 2050. And in Latin America, increased production will come from non-conventional oil, thermal, and gas sources and the amount of electricity generated is expected to increase fivefold, tripling the amount of water needed (World Energy Council, 2010). The increased demand for energy will put additional pressure on already constrained water resources.