Abstract: A method and a system are described for adapting a service provided by a base station (2) in a cellular communication network to mobile stations in its coverage area. The base station (2) is supplied with energy from a renewable energy generator (8) and/or from a back-up battery supply (10). The back-up battery supply (10) is at least partially charged by the renewable energy generator (8). The service is adapted in terms of coverage and/or capacity provided to the mobile stations as a function of the stored energy in the back-up battery supply (10) and/or as a function of a forecast regarding the amount of energy supplied by the renewable energy generator (8) over a time period.