A method of controlling energy supply in an energy distribution network (102, 104) comprising a first energy generation facility located at a first site and a second energy generation facility located at a second site, the first and second energy generation facilities adapted to supply electrical energy to the energy distribution network via different connection points (542, 544) to the network, wherein the first energy generation facility, in addition to supplying electrical energy to the energy distribution network, is configured to supply electrical energy to a further energy consumer, wherein the first energy generation facility is connected directly to the further energy consumer such that the electrical energy supplied to the further energy consumer does not pass through the distribution network, the method comprising, at a control system: receiving a first output measurement indicating electrical power output from the first energy generation facility to the energy distribution network, wherein the output from the first energy generation facility to the energy distribution network varies in dependence on electrical energy consumed from the output of the first energy generation facility by the directly connected further energy consumer; receiving a second output measurement indicating electrical power output from the second energy generation facility to the distribution network; computing a combined electrical power output to the distribution network from the first and second energy generation facilities based on the first and second output measurements; comparing the combined electrical power output to a combined electrical power output limit defined for the first and second energy generation facilities; and controlling a particular one of the energy generation facilities to adjust electrical energy output to the distribution network in dependence on the comparison, wherein the controlling step comprises reducing the electrical energy output of the particular energy generation facility such that the combined electrical power output from the first and second energy generation facilities does not exceed the combined electrical power output limit; wherein the control system is located at a given one of the energy generation facilities and wherein the output measurement from the other one of the energy generation facilities is received at the control system via a communications link between the first and second sites. receiving a first output measurement indicating electrical power output from the first energy generation facility to the energy distribution network, wherein the output from the first energy generation facility to the energy distribution network varies in dependence on electrical energy consumed from the output of the first energy generation facility by the directly connected further energy consumer; receiving a second output measurement indicating electrical power output from the second energy generation facility to the distribution network; computing a combined electrical power output to the distribution network from the first and second energy generation facilities based on the first and second output measurements; comparing the combined electrical power output to a combined electrical power output limit defined for the first and second energy generation facilities; and controlling a particular one of the energy generation facilities to adjust electrical energy output to the distribution network in dependence on the comparison, wherein the controlling step comprises reducing the electrical energy output of the particular energy generation facility such that the combined electrical power output from the first and second energy generation facilities does not exceed the combined electrical power output limit; wherein the control system is located at a given one of the energy generation facilities and wherein the output measurement from the other one of the energy generation facilities is received at the control system via a communications link between the first and second sites.