Share in other electric utilities, such as Alliant Energy (NYSE: LNT ) and P ortland General Electric (NYSE: POR ), have posted gains approaching 20 percent or more over the last year. While Portland has been downgraded by some analysts, institutional investors have continued to accumulate shares. Water Works Although they maintain a lower profile than their electric cousins, water utilities occupy a similarly important position in modern life. True, water covers 71 percent of the planet's surface, but bringing clean water to U.S. homes – and removing waste water from them – is a uniquely complicated process. American Water Works Co. (NYSE: AWK ) is the undisputed king of water utilities, serving 15 million people in 47 states. Its market capitalization hovers around $13 billion, or roughly two-and-a-half times more than its nearest competitor, Aqua America (NYSE: WTR ).