Despite remarkable advancements in technology in the last century, the problem of potable drinking water for large segments of the world’s population persists. In fact, instead of alleviating the shortage of clean water, environmental and economic conditions in recent decades have contributed to its worsening. Today, as many as 1.2 billion people face shortages of drinking water. Global warming, which in many places manifests in protracted, devastating droughts, coupled with rapidly growing populations and developing economies, makes creating and maintaining clean water supplies a critical need. But the growth in need has been accompanied by a decrease in future sources of traditional—read nonrenewable—energy. The cost of producing such energy has increased dramatically (the price of oil, for example, has gone up approximately 1500 percent since the early 1970s) and shows a long-term trend of skyrocketing even further as reserves lessen and new sources prove more difficult to access.
Water, of course, covers about 70 percent of the earth’s surface, but almost all of that is seawater, so the issue becomes converting the vast quantities of saltwater into freshwater. But the conversion of saltwater into fresh is energy intensive. Consider that the production of desalinated water costs 2.1 times more than retrieving fresh groundwater and 70 percent more than surface water, as well as the fact that energy expenditures account for 60 to 70 percent of the day-to-day operating costs of a seawater conversion plant (according to an article published by The New York Times), and it becomes imperative to understand that the clean water issue is inseparable from that of developing feasible renewable energy sources.
Progress in the science of desalinization therefore must be accompanied by better water conservation techniques, and most importantly by developments in renewable energy technology.
In other words, make energy less expensive and feasible production of clean water will follow. Solar, wind, biomass, geothermal, wave and other forms of renewables, especially when used in combination, can provide virtually uninterruptable sources of power—power that can be harnessed to fuel the production of clean water from saltwater.
Further, the development of microgrid technology means several of these renewable technologies can be deployed at virtually any location, without connection to the main power grid. For example, some remote communities in Haiti now use portable solar power charging stations to provide energy for lighting, cooking and other needs, and connect their residents to the rest of the world for the first time in their lives. On a larger scale, such technology could eventually make community-based, remote desalinization operations possible around the world, improving health, sanitation, agriculture and more. This is a future in which governments, businesses and individuals can all participate.
Although the cost of renewable energy is today still higher than traditional sources, progress in the field’s technology indicates that discrepancy is rapidly diminishing, and that within the foreseeable future renewables will be cheaper to produce.
Advancements in the areas of clean water production and renewable energy must go forward hand-in-hand to provide the quantities of freshwater needed throughout the world in the future. The cost to develop these technologies will prove less than that of finding and extracting nonrenewables, and far less than the cost in quality of life for billions of people around the world if clean water remains out of their reach.
NOTE: This blog has been entered in the Masdar “Engage: The Water-Energy Nexus” contest. See the contest entries here: www.masdar.ae/engage. And please vote for our entry at http://masdar.ae/en/adsw/detail/how-to-vote.