Yellowstone Valley Electric Cooperative is offering wind generated power to its residential and commercial customers.   Wind power is being offered to YVEC by the Bonneville Power Administration.  Because of the increased cost of wind generated power, YVEC will charge an extra two cents per kilowatt hour to cover this additional cost.   YVEC customers will be able to purchase all or just a portion of their monthly electric needs in the form of wind power.  YVEC will be offering blocks of wind power for purchase. Each block will consist of 100 kilowatt-hours. A minimum of two blocks, or 200 kilowatt-hours, must be purchased per month to participate in the wind power program.