Are there any solar installation companies in North Iowa or Southern Minnesota?

One of the best sources for identifying contractors with special accreditation for the sales and installation of solar energy products is the North American Board of Certified Energy Practitioners (NABCEP) . They offer certification and certificate program to renewable energy professionals throughout North America. You can locate certified practitioners in your area from their website.  Additionally, the Iowa Renewable Energy Association, IRENEW, publishes the Sourcebook as one of their resources which contains a searchable database of renewable energy professionals in Iowa. You can find the Sourcebook on their website