Some states require that a portion of electricity be generated by renewable resources. The utilities in those states are sometimes given the opportunity to either build new renewable facilities or purchase the renewable attributes from other utilities. This creates a market for the renewable attributes of wind facilities. Recognizing this, NPPD has actively marketed the green attributes from the Ainsworth facility. This effort has resulted in the sale of most of the wind attributes from this facility. This additional revenue provides economic benefit to NPPD and its customers.