What does northwestern energy do? The Northwestern Energy, located in Mitchell, SD, is an utility company that provides public services for Mitchell residents. In Davison County, Utility Companies provide electricity, natural gas, water, and sewer services.Where is northwestern energy in mitchell sd? Address, Phone Number, Fax Number, and Hours for Northwestern Energy, an Utilities, at North Main Street, Mitchell SD. View map of Northwestern Energy, and get driving directions from your location . Find 6 Utility Companies within 31.2 miles of Northwestern Energy.How do i make payments on my northwestern energy account? Choose the option that is best for you! Make a one-time payment instantly online for free with your checking or savings account or with a credit or debit card for a $1.99 processing fee. No registration required. Use your bank's online payment to make payments on your NorthWestern Energy account.