polar hat section of self deploying windfarm. Make sure you have enough BABs/wind turbines and foundations in inventory when placing to benefit from the automatic deployment. Once it's done building, BABs can be removed for reuse.
Youtube: https://youtu.be/o5B71HC5YFk
Reddit: https://www.reddit.com/r/Dyson_Sphere_Program/comments/1kznvup/selfdeploying_windfarm_blueprints_for_the/