In the Smart Grid environment, one novel concept is the microgrid, which can be either a very small entity or a larger one. For example, the microgrid can consists of resources of an individual small customer or of several customers each with their own energy resources inside a low-voltage network. The microgrid can also consist of a large area with various energy resources and a connection to the distribution grid. Especially, when the number of these large-scale microgrids increases, a central question is what kind of network tariff structure should be applied to them. The network tariffs can affect whether the microgrids will have a connection to the distribution grid. In this paper, a novel tariff structure for a large-scale microgrid is proposed. The results show that the benefits of the microgrid can be shared more fairly between it and the distribution system by applying a novel network tariff.