Residential electrical distribution units

The North American electric power transmission system has been described as the largest, most complex machine ever built by humanity. It is a massive network of generating stations, transmission lines, substations, distribution lines, motors, and other electrical loads all interdependently linked for the conversion, transportation, and control of electrical energy. Approximately 60 percent of all energy utilized in the United States passes through the interconnected electric power system. The major goal of the system is to most efficiently and reliably deliver electric power from generating stations to residential, commercial, and industrial consumers. 

The American Gas Association forecasts that, by 2020, on-site power at industrial facilities or distributed generation in commercial or even residential locations will account for 20 percent of all new capacity, or 5 percent of all electricity generated in the United States. 

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