The discussion paper analyses the integration of power-to-gas plants into the energy and regulatory framework in Germany. For this purpose, four power purchase options of the plants are compared and their influence on the power purchase path, the purchase costs, the green power characteristics, and the competitiveness of the plant is examined. It is shown that business models based on the power purchase options have fundamental peculiarities, as the plants are operated either in a regulated or in a market environment and thus require different investment incentives.