A specialized, centrally dispatched, spot market for power that functions as a short-term market in establishing the short-term clearing price while providing a system of long-term transmission contracts. Pool regulation guarantees open access, comparable service and cost recovery, making ancillary generation services (load following, spinning reserve, backup power, reactive power) available to all market participants on comparable terms. A PoolCo also provides settlement mechanisms for differences in contracted volumes between buyers and sellers.