The Devers substation north of Palm Springs distributes power through the Coachella Valley. The power grid covers the Western United States like a massive spider web, its interwoven strands spun from 115,000 miles of transmission lines that stretch from British Columbia to Mexico. It s an infuriatingly complicated system that experts frequently liken to water when trying to explain the workings of something that no one can see. Power will look for the path of least impedance, or least resistance, said Armando Perez, director of grid planning for the California Independent System Operator, which manages power flow on the grid in most of California.
Water managers use dams, canals, pipes and pumps to move water where they want it.
Power managers use copper wire, transmission lines and substations to take electricity, usually generated at 14,000 volts to 16,000 volts and ramped up to 500,000 volts so it can be moved on heavy-duty power lines, Perez said. Higher voltage power moves better because when more power is packed into a transmission line the power moves faster. It s like water under pressure moving faster. Using higher voltage also lessens the chance of power leaking from a line. Heavy-duty lines that can handle 500,000 volts form the thick, main branches of the grid that link major urban areas and may cross state boundaries, said Lorie O Donley, a spokeswoman for the California system.