An installation includes an in-building hot water supply system, a hot water heat pump, an energy storage arrangement containing a mass of phase change material and a heat exchanger coupled between the hot water system and the heat pump, and a processor to provide a signal to the heat pump based on the opening of an outlet of the hot water supply system. The mass of phase change material has enough latent heat capacity to heat to a predetermined temperature a predetermined quantity of water in the interval from the opening of an outlet of the hot water supply system until at least the heat pump begins to heat water in the hot water supply system. Also provided is a method of controlling a heat pump in such an installation.

Provided is a method of controlling a supply of heated water from a source including a heating appliance (301) to a plurality of water outlets (302, 303) remote from the heating appliance, the method comprising: detecting a demand for water from a first water outlet (302), identifying the demand as likely to be associated with the first water outlet (302) and setting to a first target water temperature value, associated with the first outlet, a target water temperature for the temperature at which water is supplied; detecting a demand for water from a second water outlet (303), identifying the demand as likely to be associated with the second water outlet, and resetting to a second target water temperature value, associated with the second outlet, the target water temperature at which water is supplied; wherein the demand is associated with an outlet based on a detected flow characteristic. Also provided is a hot-water supply installation having a plurality of controllable outlets, the installation including: a source of hot-water with an outlet having a controllable outflow temperature; a flow measurement device to provide data on water flow between the source and the plurality of controllable outlets; a temperature sensor to detect the outflow temperature; a memory storing parameters linking flow data to outlet identity, and associating each of the plurality of controllable outlets with a respective target temperature; a processor operatively connected to the memory, the flow measurement device, and the first temperature sensor; the processor being configured: in the event that one of the plurality of controllable outlets is opened, to determine based on a detected flow characteristic which of the plurality of controllable outlets has been opened, and then based on that determination to control the outflow temperature of the source, in accordance with stored parameters for the determined one of the controllable outlets; and in the event that another of the plurality of controllable outlets is opened, to determine which another of the plurality of controllable outlets has been opened, and then based on that determination to control the outflow temperature of the source, in accordance with stored parameters for the determined another of the controllable outlets.

Provided is a heating installation including an energy store including a latent heat energy storage medium, and a heat pump having a defrost cycle, the heating installation including a hot water supply system arranged to supply instantaneous heated water and space heating to a building, and a processor to control the installation. The processor being configured to: control the supply of heat from the heat pump to the latent heat energy storage medium to store heat for heating water and to a heating circuit for providing space heating; and estimate a likelihood of a defrost cycle by the heat pump. In anticipation of an impending defrost cycle, the processor further being configured to control operation of the installation to store additional energy by at least one of: heating the latent heat energy storage medium to a higher level than a level set for anticipated water heating demand alone and/or heating the building and/or circulating heating fluid of the installation to a higher level than a level set for desired building heating; to compensate for an absence of heat from the heat pump during the impending defrost cycle.

Energy storage systems include a heat source and a thermal energy storage system to store thermal energy produced by the heat source. The thermal energy storage system includes a first tank containing a first salt having a first melting temperature and a second tank containing a second salt having a second melting temperature. At least one input conduit is configured for transferring thermal energy from the heat source to the first tank and second tank. A first output conduit is in thermal communication with the first tank. A second output conduit is in thermal communication with the second tank. Additional energy storage systems include a heat booster positioned and configured to add thermal energy to a heated heat transfer fluid prior to reaching a tank containing at least one thermal storage material. Methods include transferring thermal energy from a thermal energy source to a plurality of thermal energy storage tanks.

A heating system for heating a fluid received at an inlet, the system including a first heating device disposed in a first heated line branched from the inlet, wherein a first flow of the fluid through the first heated line is configured to be modulated by a first valve; a second heating device disposed in a second heated line branched from the inlet, wherein a second flow of the fluid through the second heated line is configured to be modulated by a second valve; and a bypass line and a third valve disposed in the bypass line, wherein a flow through the bypass line is configured to be modulated by the third valve, wherein the first and second heating devices and the first, second and third valve are configured to cooperate to heat the fluid at an outlet received from the first and second heated line and the bypass line.

Disclosed is a method of mapping an in-building water supply installation having multiple controllable water outlets, the installation including a supply of water; in a water flow path between the supply of water and the controllable water outlets, a flow measurement device and a flow regulator; a processor being operatively connected to the flow measurement device and the at least one flow regulator. The method comprises opening a first of the water outlets and processing signals from the flow measurement device with the processor at least until a first flow characteristic is determined; closing the first of the water outlets; repeating the opening, processing and closing operations for each of the other water outlets to determine for each controllable water outlet a respective flow characteristic. Subsequently the processor is configured to; identify the opening of a particular one of the plurality of controllable water outlets based on the similarity of a detected flow characteristic to a respective flow characteristic; and control said at least one flow regulator, based on the identification, to control a supply of water to the identified controllable water outlet.

Provided is a method of disinfecting a hot water supply system having a plurality of controllable hot-water outlets and a water heating arrangement including an energy store comprising a phase change material that has a phase transition temperature of less than 60 Celsius, the method comprising: informing an operator of a future disinfection event; increasing a hot water supply temperature from a pre-event temperature of less than 60 Celsius to a disinfection temperature; providing a signal to the operator to cause the operator to open a first of the hot water outlets; providing a signal to the operator to close the first outlet after a disinfection period; providing a signal to the operator to open another hot water outlet; providing a signal to the operator to close the another hot water outlet after a disinfection period; and repeating the signalling to the operator to open and then, after a disinfection period, to close each of the plurality of controllable hot-water outlets; reducing the hot water supply temperature to the pre-event temperature of less than 60 Celsius from the disinfection temperature; and indicating to the operator the completion of the disinfection event. A corresponding hot water supply system is also provided, the system preferably including a heat pump.

Disclosed is a method of mapping an in-building water supply installation having multiple controllable water outlets, the installation including a supply of water; in a water flow path between the supply of water and the controllable water outlets, a flow measurement device and a flow regulator; a processor being operatively connected to the flow measurement device and the at least one flow regulator. The method comprises opening a first of the water outlets and processing signals from the flow measurement device with the processor at least until a first flow characteristic is determined; closing the first of the water outlets; repeating the opening, processing and closing operations for each of the other water outlets to determine for each controllable water outlet a respective flow characteristic. Subsequently the processor is configured to; identify the opening of a particular one of the plurality of controllable water outlets based on the similarity of a detected flow characteristic to a respective flow characteristic; and control said at least one flow regulator, based on the identification, to control a supply of water to the identified controllable water outlet.

There is herein described energy storage systems. More particularly, there is herein described thermal energy storage systems and use of energy storable material such as phase change material in the provision of heating and/or cooling systems in, for example, domestic dwellings.

There is herein defined phase change material (PCM) battery designs which are heated. More particularly, there is described integrally and/or internally located heating devices (e.g. electrical heating devices) in a range of heat batteries containing PCM. In particular, there is described a PCM heat battery comprising: a PCM enclosure capable of holding PCM; PCM located in the enclosure; an electronic control system for the PCM heat battery; a heating device located in the PCM heat battery; wherein the heating device is capable of heating and/or charging the PCM.