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The photo on the left shows a wind turbine generator assembly from the Gundersen Health System Envision® wind project in Lewiston, MN. Once completed, the generators become the heart of the unit within the nacelle at the top of the turbine. This particular design utilizes four generators and you can see three of them in the photo of this incomplete assembly. The generators produce direct current (DC) power in the nacelle, which is transported to the bottom of the tower through copper busbars. The photo on the right shows a view looking upward from the inside of a tower. You can see the busbars that transport the DC electricity on the left side of the photo. Once the power reaches the bottom of the tower an inverter converts the DC electricity to alternating current (AC) power. The power then exits the structure through cables and an underground vault in the foundation. The power then proceeds to a power distribution panel (PDP) and a pad mount transformer (PMT,) which sit on concrete pads outside of the tower. The PMT “steps-up” the power to 34.5 kilovolts (KV) at the Lewiston site and is then sent through underground cables to the project substation several hundred yards away where it is transformed again to grid level voltage for consumption.