Low Carbon Desalination: Status and Research, Development, and Demonstration Needs, Report of a workshop conducted at the Massachusetts Institute of Technology in association with the Global Clean Water Desalination Alliance

Abstract

Water demand is increasing worldwide as a result of growing populations and rising standards of living. Further, increasing climate variability is disrupting historical patterns of precipitation and water storage. While conservation and reuse efforts have helped to moderate demand for new freshwater resources in some locations, desalination technology is increasingly being used to meet demand worldwide. Currently installed capacity is almost 90 million m3/day (90 billion liters per day) of desalinated water, a value that has been growing rapidly, with growth projected at 12% over the next five years. Energy consumption is the major cost of desalination, accounting for more than 1/3 of the cost of water in modern plants, and energy use also represents the major environmental impact of desalination. Thus, desalination using low-cost energy sources that have low greenhouse gas emission is highly desirable. Participants in the workshop contributed prewritten material on research and development needs that they regarded as critical to the reduction of the global warming potential (GWP) of desalination. These inputs form the bulk of this report. The workshop itself was devoted to a vigorous and wide-ranging discussion of the opportunities and priorities for powering desalination systems with low-carbon energy in the context of current and emerging trends in desalination and energy production. The report summarizes the experts’ assessment of available technologies and their recommendations for research, development, and demonstration (RD&D) of low carbon desalination. A major conclusion of this workshop is that currently available energy and desalination technologies can be effectively combined to reduce desalination’s GWP in the near term. Keywords: Desalination, renewable energy, solar energy, wind power, climate change mitigation, nuclear energy, battery, electric grid, membranes, fouling, CO2, cost analysis, case studies