Electricity infrastructure resilience and security

The North American power network may be considered the largest and most complex machine in the world-its transmission lines connect all the electric generation and distribution on the continent. In that respect, it exemplifies many of the complexities of electric power infrastructure and how technological innovation combined with efficient markets and policies can address them. This network represents an enormous investment, including over 15,000 generators in 10,000 power plants, and hundreds of thousands of miles of transmission lines and distribution networks, whose estimated worth is over U.S. $800 billion. In 2000, transmission and distribution cables alone were valued at U.S. $358 billion [9-16]. The National Academy of Engineering classified North American electric power grid as the greatest engineering achievement of the twentieth century. Today, the North American electric power grid is a network of approximately 10,000 power plants, 450,000 miles of high-voltage (>100 kV) transmission lines, over 6 million miles of lower voltage distribution lines in the United States, and more than 15,000 substations. The transmission system is an interstate grid whose primary purpose is to connect generating plants with electrical load centers like cities and with high demand commercial and industrial facilities. In turn, the local distribution system provides for service to residential, commercial, and small business customers.