Power distribution control of combined heat and power generation apparatus over a network

A temperature control apparatus for a building, the apparatus comprising: an electricity generator, operable to contribute to an electrical power supply for consumer appliances at the building; a heat transfer circuit adapted to circulate heat transfer fluid to cool the electricity generator; a heating system comprising a heat source for providing heat energy to a space heater for heating at least one zone of the building and to a hot water tank arranged to store a supply of hot water for the building, and a heat exchanger adapted to supplement the heat energy from the heat source with heat energy obtained from the heat transfer circuit; a user interface adapted to enable a user to select at least one of (a) a desired temperature for the at least one zone of the building, and a first time period during which the desired temperature is to be maintained; and (b) a second time period for the supply of hot water from the hot water tank; and the apparatus further comprising: a controller configured to determine when to operate the electricity generator based on at least one of: (i) the thermal capacity of the hot water tank; and (ii) the first time period, the desired temperature and the current temperature of the at least one zone of the building.