plications, among others. These data were collected for the International Desalination Association’s Worldwide Desalting Plant Inventory, which also includes facilities that use desalination technologies (e.g., reverse osmosis, nanofiltration) to remove salinity in the treatment of wastewater for reuse/reclamation, although reuse is not a focus of this report. The worldwide desalination capacity has approximately doubled since 1995 and continues to grow steadily. Nearly half (47 percent) of the current online global desalination capacity is located in the Middle East (Figure 2-2). North America, Europe, and Asia each have about 15 percent of the global online desalination capacity (GWI, 2006b).
The choice of desalination technology is a site-specific combination of many factors, including energy availability and form, source water quality, and other local conditions. Globally, thermal and membrane processes are the two major processes in use. In the United States, reverse osmosis and other membrane systems account for nearly 96 percent of U.S. online desalination capacity (see Figure 2-3) and 100 percent of the municipal desalination capacity (Mickley, 2006). Desalination tech-