
Electricity is critical to every aspect of modern life. The United States’ national security, economy, and public health and safety rely on the North American electric grid every second of the day. These, and many other functions powered by the grid have likely experienced local outages caused by weather, accidents, or sometimes from tree branches falling on power lines. Larger power outages, however, are infrequent occurrences, due in part to an array of organizations that work tirelessly to ensure the grid remains reliable, resilient, and secure. Nonetheless, it is neither practical nor possible to prevent all disruptive events. Grid owners and operators balance risk, investment, and cost to customers when making investments in their systems.