This US Department of Energy video explains how solar panels generate electricity. In your research, you may have found out that there are different types of solar panels. The type of solar panels installed is one of several factors that can effect energy production. This will be something you will want to discuss with the installer.
In most cases, when you have made a decision to invest in a solar system, it will be connected to a utility provider, i.e., Ameren Missouri / Illinois or a Co-op utility provider. Heartland Alternative Energy (HAE) is a Trade Ally of Ameren Missouri and Ameren Illinois. They also work with the Co-op Utility providers throughout Missouri. HAE will help you every step of the way in understanding and completing the registration process.