A CHP optimal dispatching model is a mixed integer programming model and is used for a district heating system (DHS) comprising a heat source, a heating network and a heat load, and the heating network comprises a heat transmission network and a heat distribution network. A plurality of heating areas is divided, and one day is divided into a plurality of time periods; the heat transmission loss of the heat distribution network is omitted, and a heat transmission network model taking transmission time delay of the heating network into consideration is established according to the heat transmission network; a terminal heat consumer model capable of reflecting indoor temperature is established; and a combined optimal dispatching model comprising conventional generators, wind power units, CHP units, electric boilers and heat storage tanks is established.

Heat pump system (100) comprising at least one heat medium circuit (210,220,230,240,250,310,320,410,420,430,440,450,460) in turn comprising a compressor (211), an expansion valve (232,242), at least two different primary heat sources or sinks selected from outdoor air, a water body, the ground or exhaust air, at least one of two different secondary heat sources or sinks selected from indoors air, pool water and tap water, a respective temperature sensor (412,432) at each of said primary heat sources or sinks, a valve means (421,431,451) for selectively directing the primary-side heat medium to at least one of said primary heat exchanging means, and a control means (500). The invention is characterised in that, in a secondary-side heating operating mode, the temperature of said primary heat sources or sinksis measured, and in that the primary-side heat medium is directed only to the primary heat exchanging means associated with the heat sources or sinks with the highest temperature. The invention also relates to a method.

A combined hot water and air heating and conditioning system including a first heat exchanger, a heat pump, a chilling tower loop, a burner and a second heat exchanger to provide hot water, air heating and air cooling. The system provides hot water, air heating and cooling all in one single unit. The system utilizes a heat pump to remove heat from ambient air and transfer the rejected heat into a hot water system, thereby using waste heat to heat the hot water system. The system utilizes a heat exchanger not only for the purpose of transferring heat from a heating source to a fluid in the heat exchanger but also for the purpose of dissipating heat from the fluid in the heat exchanger to the surroundings of the heat exchanger, thereby allowing a heat pump to act both as an air heating and conditioning device.

A heat pump network is described. In one aspect a distributed heat pump network used in a district heating architecture is described.

A district energy system includes at least one energy provisioning unit, an energy management controller; a thermal distribution network coupled to the energy provisioning units and to a plurality of coupling interfaces connectable to the associated HVAC system of buildings within a district, and an electrical distribution network coupled to the energy provisioning units and to the coupling interfaces. The coupling interfaces may include both heat pumps and heat exchangers at each building, to provide heating, cooling and enable harvesting of normally wasted thermal energy from the buildings for re-distribution. The controller can manage the selection and number of energy provisioning units (and their operational set points) coupled to the district thermal distribution network and the electrical distribution network to meet the thermal and electrical demands of the district while satisfying other operational goals such as the minimization of greenhouse gas emissions.

A solar photovoltaic (PV) water heating system includes a tank including at least a first heating unit having at least first and second heating elements, at least one of which is switchable; a PV solar collector; an inverter adapted to convert the output from the PV collector to an alternating power supply; a modulator to modulate the alternating power supply from the inverter; a controller adapted to control the modulator and the switching of the or each switchable heating element; wherein the controller is adapted to control the modulator and the switchable heating elements to maximize the energy drawn from the PV collector.

A solar photovoltaic (PV) water heating system includes a tank including at least a first heating unit having at least first and second heating elements, at least one of which is switchable; a PV solar collector; an inverter adapted to convert the output from the PV collector to an alternating power supply; a modulator to modulate the alternating power supply from the inverter; a controller adapted to control the modulator and the switching of the or each switchable heating element; wherein the controller is adapted to control the modulator and the switchable heating elements to maximize the energy drawn from the PV collector.

A solar photovoltaic (PV) water heating system includes a tank (1.020) including at least a first heating unit (1.016) having at least first and second heating elements (1.016.1 . . . 1.016.x), at least one of which is switchable (1.014.1A . . . 1.014.1m); a PV solar collector (1.002); an inverter (1.004) adapted to convert the output from the PV collector to an alternating power supply; a modulator (1.060) to modulate the alternating power supply from the inverter; a controller (1.040) adapted to control the modulator and the switching of the or each switchable heating element; wherein the controller is adapted to control the modulator and the switchable heating elements to maximize the energy drawn from the PC collector.

A climate control system is operated by receiving climate information from climate control input devices at one or more plugin modules. The climate information is communicated from the plugin modules to a main control unit, which determines operating instructions for climate output devices and air inlets. When it is detected that the main control unit is not operational, the control system switches to a standby control unit if so equipped. The climate information is then communicated from the plugin modules to the standby control unit. The standby control unit determines operating instructions for the climate output devices and air inlets based on the climate information. When it is detected that the standby control unit is also not operational, the plugin modules switch to an autonomous mode such that operating instructions for the climate output devices and air inlets are determined by the plugin modules.

A multi-pipe-switching heat exchange apparatus has a heating module, an auxiliary module, a buffering module, and an operation module. The heating module has at least one heating boiler. The auxiliary module is deposited beside the heating module and has at least one spare boiler. The buffering module is connected to and communicates with the heating module and the auxiliary module, and has a buffering body connected to and communicating with the at least one heating boiler and the at least one spare boiler, a first pipeline set deposited between the buffering body and the heating module, and a second pipeline set deposited between the buffering body and the auxiliary module. The operation module is connected to and communicates with the buffering module and has an operation end and a third pipeline set connected to and communicating with the buffering body and the operation end.