On October 1, the grid operator for most of California will begin simulating the balancing of subhourly electricity supply and demand for PacifiCorp 's electric service areas in the western U.S. through an energy imbalance market . By adding its generation resources to the resource pool of the California Independent System Operator to meet subhourly electricity imbalances, PacifiCorp anticipates enhanced reliability and cost savings, particularly in the face of higher levels of renewable energy generation in the West.