A method carries out an outside temperature-dependent control of at least one thermal power indicative parameter of a supply temperature of a first heating or cooling system in a first building (H). The control is carried out on the basis of the at least one thermal power indicative parameter. The at least one thermal power indicative parameter is indicative of the heat consumption or of the cooling power of at least one second heating or cooling system of a second building (H′, H″, H′″), located at a distance from the first building, and is received via a data network (1), in particular, via the Internet. An arrangement is provided for controlling a first heating or cooling system of a first building, wherein the arrangement is adapted to carry out the method mentioned above. A server is further provided that is adapted to receive at least one thermal power indicative parameter.