Exelon(EXC -0.12%) is a dominant force among the nation's utilities companies. In this video, Motley Fool energy analyst Taylor Muckerman gives us three reasons why he sees it as a buy. The company is widely diversified in the sources of the energy it provides, and because such a low percentage of that energy comes from coal and a high percentage comes from nuclear, Exelon is particularly insulated against federal EPA regulations on emissions standards. This means it can reliably provide a strong base load power supply from its world-class nuclear fleet with little to no threat to that industry. As well, Exelon is a dividend leader among its peers.