The water and energy technology research focuses on improving the efficiency of energy and water use in water delivery, supply and treatment. Globally, seven percent of energy is used to deliver water; energy is also an input in water treatment. Only 2.5 percent of earth's water supply is fresh. In the U.S., 39% of freshwater withdrawals are used to generate electricity. As world population grows, water supplies are growing increasingly short, and new ways of efficiently using water and energy together need to be developed.