PLUMBING SYSTEM

Description

CROSS REFERENCE

This application claims priority to UK Application No. 2410116.4, filed Jul. 11, 2024, the entirety of which is hereby incorporated by reference.

FIELD OF THE INVENTION

This disclosure relates to plumbing systems, particularly, but not exclusively to ablutionary systems.

BACKGROUND OF THE INVENTION

Water used in an ablutionary system may not be suitable for immediate reuse, due to its becoming contaminated. A substantial amount of energy may be required to increase the temperature of mains supply water to typical showering temperatures. When this water is used in an ablutionary system such as a shower system, it flows into a drain, often while still being at a temperature significantly higher than the temperature of the mains supply water. This waste water may therefore contain a substantially higher heat energy than, for example, the supply water. It may be desirable within a plumbing system or an ablutionary system to recover at least some heat energy from this waste water.

Prices charged for peak and off-peak energy usage may be significantly different. Therefore, it may be of economic benefit for a household to shift as much energy usage as possible to its off-peak hours.

Furthermore, some types of renewable electricity have differing times of peak supply capability and peak demand.

It may be desirable to provide a plumbing system or an ablutionary system, which may reduce total energy usage by reducing wasted energy and/or may reduce the cost of energy purchase from an energy supplier, ideally without requiring any significant adjustment to a user's ablutionary habits.

BRIEF DESCRIPTION OF THE DRAWINGS

Example implementations will now be described with reference to the accompanying drawings, in which:

FIG. 1 shows a schematic view of an example of a plumbing system.

FIG. 2 shows a schematic view of another example of a plumbing system.

FIG. 3 shows a schematic view of another example of a plumbing system.

FIG. 4 shows a schematic view of another example of a plumbing system.

FIG. 5 shows a schematic representation of a method of using a plumbing system.

DETAILED DESCRIPTION OF THE DRAWINGS

A first aspect provides a plumbing or ablutionary system comprising: a mixing device configured to receive at least one temperature-adjusted water supply stream and operable to provide at least one principal stream having a controlled temperature; at least one fluid delivery device downstream of the mixing device, one or more of the fluid delivery devices being arranged to receive one or more of the principal streams and to emit water therefrom; at least one receptacle arranged to collect water emitted, in use, by one or more of the fluid delivery devices and comprising a waste; a heat exchange apparatus configured to receive a water supply stream and a waste water stream from the waste such that the water supply stream and the waste water stream are in a heat exchanging relationship as they pass through the heat exchange apparatus, thereby producing, in use, the temperature-adjusted water supply stream; wherein the mixing device comprises a thermal battery.

When the waste water stream has a higher temperature than the water supply stream heat is exchanged from the waste water stream to the water supply stream, thereby increasing the temperature of the water supply stream prior to its being received as one or more of the temperature-adjusted water supply streams by the mixing device. In such a case, a given temperature-adjusted water supply stream(s) may be termed a warmed water supply stream or a pre-heated water supply stream.

By providing a warmed water supply stream or a pre-heated water supply stream to the mixing device, the meant configured to receive at least one temperature-adjusted water supply stream and operable to provide at least one principal stream having a controlled temperature may not need to expend as much energy in providing the at least one principal stream having a controlled temperature. The controlled temperature may be a user-selected temperature. In an ablutionary system such as a shower system, sink system, or other fluid dispensing system, the controlled temperature may typically be approximately 40° C.

The term waste water stream may be used to refer to the water that is collected by the at least one receptacle and then flows through the waste towards the heat exchange apparatus.

In implementations, the system may be configured such that a majority of, substantially all or all of the waste water stream is received by and passes through the heat exchange apparatus.

The heat exchange apparatus may be configured such that the waste water stream and the water supply stream do not come into contact with each other.

At least one of the at least one fluid delivery devices may comprise a sprayer for a shower.

The heat exchange apparatus may be any suitable heat exchange apparatus, for example, it may be shell and tube heat exchanger, or it may be a parallel flow heat exchanger, or it may be a counterflow heat exchanger, or it may be a double pipe heat exchanger, or it may be a horizontal waste water heat recovery system.

The heat exchange apparatus may comprise: a first heat exchange conduit for conveying a waste water stream, the first heat exchange conduit extending from a waste water inlet for receiving the waste water stream from the waste to a waste water outlet; and a second heat exchange conduit for conveying the water supply stream, the second heat exchange conduit extending from a water supply inlet for receiving the water supply stream to a water supply outlet; wherein the first heat exchange conduit and the second heat exchange conduit are arranged such that, in use, the water supply stream flowing through the second heat exchange conduit from the water supply inlet to the water supply outlet and the waste water stream flowing through the first heat exchange conduit from the waste water inlet to the waste water outlet are in a heat exchanging relationship; wherein when the waste water stream has a higher temperature than the water supply stream heat is exchanged from the waste water stream to the water supply stream, thereby increasing the temperature of the water supply stream prior to its being received by the mixing device.

The heat exchange apparatus may be disposed at least partially beneath one or more of the receptacles. For example, if one of the receptacles is a shower tray, the heat exchange apparatus may be disposed at least partially beneath the shower tray. Such an arrangement may make the plumbing system more compact. Such an arrangement may reduce waste water heat energy that is lost by being emitted to the surroundings by virtue of the relatively short distance the waste water stream has to travel before entering the heat exchange apparatus.

The thermal battery may be operable to heat water flowing therethrough.

The thermal battery may comprise a phase change material thermal battery and/or an encapsulated thermal battery. The thermal battery may comprise a heating element configured to provide energy to the thermal battery.

The phase change material thermal battery may comprise one or more phase change materials. The person skilled in the art may be aware of various examples of suitable phase change materials. Examples of suitable phase change materials may include waxes, paraffins and oils such as plant-derived oils. The phase change materials(s) may be organic or inorganic. The phase change material(s) may include a salt water mixture with one or more additives.

The phase change material(s) may be selected to have a high latent heat capacity at a narrow temperature range which can achieve a high energy density compared with water.

The thermal battery may comprise multiple paths for water to flow through it, which may be selectable to control the time that water takes to flow through the thermal battery.

The thermal battery may be operably connected to a heat pump.

The thermal battery may comprise a heating element. The heating element may be an electrical heating element. The heating element may be a low power heating element.

The heating element may be operably connected to one or more sources of electricity, including, for example, a mains electricity supply and/or a local source of electricity.

A controller may be operably connected to the thermal battery, e.g. the controller may be operably connected to the heating element. The controller may be operable to control operation of the thermal battery, e.g. the heating element, whenever required, in use. In example implementations, the controller may be configured to be programmable or controllable to allow operation of the thermal battery, e.g. the heating element, whenever required, at off-peak times and/or other times when electricity may be relatively cheap.

In an example embodiment, in use, the thermal battery may be charged during times of off-peak energy usage. The cost per unit of energy can be significantly cheaper during times of off-peak energy usage. A user, showering at peak energy usage times, can therefore pay a reduced cost for the same showering usage.

In use, the thermal battery may be charged at peak supply times and used at peak demand time. This may mitigate the problem of mismatched peak supply and demand times. For example, the thermal battery may be charged at midday using solar electricity and then used for an evening/night-time shower.

The temperature to which water is heated by flowing through the thermal battery may be controlled by varying the flow rate of water through the thermal battery. The lower the flow rate is, the higher the energy transfer from the thermal battery to the water will be. The temperature may be controlled by varying the length of flow channels in the battery with a constant flow rate of water through the channels.

The mixing device may comprise a mixer. The mixer may be downstream of the thermal battery. The mixer may be configured to mix at least two water supply streams and provide at least one principal stream at a controlled temperature and, optionally, flow rate, wherein one of the water supply streams received by the mixer comes from the thermal battery. The mixer may be a digital mixer valve. The mixer may be operable to control individually the flow rate of the at least two water supply streams entering it. The mixer may comprise a thermostatic valve. The mixer may comprise a mixing chamber. A digital mixer valve may allow more precise control over the flow and temperature characteristics of the at least one principal stream.

In implementations comprising a mixer, any given water supply stream received by the mixer other than the water supply stream that comes from the thermal battery may or may not have passed through the heat exchange apparatus.

The ablutionary system may be a shower system. The term shower system may be understood to refer to any ablutionary system, in which at least one of the fluid delivery devices is a sprayer for a shower, e.g. a handheld shower or an overhead shower.

In implementations, one or more of the receptacles may include a shower tray, at least a portion of a floor of an ablutionary setting or part thereof, a bath tub, a basin, a sink or the like.

A given receptacle may comprise more than one waste.

A second aspect provides a method of using a plumbing or ablutionary system, e.g. a plumbing or ablutionary system according to the present disclosure such as a plumbing or ablutionary system according to the first aspect, the method comprising: a first step, wherein the or a thermal battery is charged to a predetermined energy level; a second step, wherein the or a mixing device operates to provide at least one principal stream at a controlled temperature that is emitted by at least one fluid delivery device; a third step wherein the water emitted by one or more of the fluid delivery devices is collected by the or a receptacle and the water collected by the receptacle enters a waste; a fourth step, wherein a waste water stream is conveyed from the waste to the or a heat exchange apparatus; and a fifth step, wherein the waste water stream entering the heat exchange apparatus exchanges heat with the or a supply water stream, thereby providing a temperature-adjusted water supply stream; and a sixth step, conveying at least a portion of the temperature-adjusted water supply stream to the mixing device.

In implementations, the second, third, fourth, fifth and sixth step may be repeated, in use, as long as is desired or until the thermal battery is depleted of energy.

The method may recover heat energy from the waste water stream and gives access to on-demand hot water, wherein the energy used in the thermal battery to heat the water can be stored at a different time to the time that it is used. This may allow a user to, for example, take advantage of off-peak energy prices if the thermal battery is charged during off-peak energy usage times.

The thermal battery may also be charged using off-grid electricity. The thermal battery may be charged using renewable electricity such as solar power or wind power or geothermal power. The thermal battery may be charged using a heat pump.

Furthermore, while the apparatus has been described as being used to heat water and recover heat energy from waste water, the skilled person will appreciate that the apparatus and method described could also be used to chill water. A heat exchanger could reduce the heat energy of water in the water supply stream and increase the heat energy of water in the waste water stream, thereby pre-cooling the supply stream. Used in this manner, the invention may be of benefit when the water supply stream is at a temperature higher than desired for use out of the fluid delivery device, particularly when the fluid delivery device is a showerhead. In countries with regular hot weather that employ the use of water tanks on the roofs of houses for example, usage of the invention in the manner here described may be useful in reducing the temperature of heated water in the water tanks to appropriate showering temperatures.

The skilled person will appreciate that except where mutually exclusive, a feature or parameter described in relation to any one of the above aspects may be applied to any other aspect. Furthermore, except where mutually exclusive, any feature or parameter described herein may be applied to any aspect and/or combined with any other feature or parameter described herein.

FIG. 1 shows a schematic view of an example of a plumbing system 100.

A showerhead 101 is attached to a wall 110, the showerhead 101 being operable to emit water towards a shower tray 102. The shower tray 102 is configured to collect water emitted from the showerhead 101. The shower tray 102 comprises a waste which is connected to a first drain pipe 103.

The first drain pipe 103 leads to a heat exchanger 105. The water which flows into the heat exchanger 105 via the first drain pipe 103 exits the heat exchanger 105 via a second drain pipe 106.

A water supply pipe 104 is connected to the heat exchanger 105. The water which flows into the heat exchanger 105 via the water supply pipe 104 exits the heat exchanger 105 via a pre-heated water supply pipe 107.

The pre-heated water supply pipe 107 is connected to the heat exchanger 105 at a first end and to a thermal battery 108 at a second end.

A principal stream pipe 109 is connected to the thermal battery 108 at a first end and to the showerhead 101 at a second end. The second end of the principal stream pipe 109 may be connected directly or indirectly to the showerhead 101.

The showerhead 101 is shown in FIG. 1 to be connected to the wall 110 of the ablutionary setting, but it is appreciated by the skilled person that it could equally be connected to any surface in the ablutionary setting, for example, the ceiling or the floor if so desired. There may be a plurality of showerheads. The showerhead 101 may be operable by a user to control its flow. Any device for emitting water may be employed in place of the showerhead.

In use, the shower tray 102 collects water emitted by the showerhead 101, but it is appreciated that it need not be a shower tray. For example, a bathtub or the floor of a wet room or part thereof comprising a waste connected to the first drain pipe 103 could replace the shower tray 102. Any receptacle capable of collecting water emitted by the showerhead 101 and comprising a waste connected to the first drain pipe 103 could work in place of the shower tray 102. The shower tray 102 may comprise a plurality of wastes connected such that their combined flow enters the first drain pipe 103.

The water supply pipe 104 may convey water from any suitable water source to the heat exchanger 105. For example, it may convey water from a mains water supply, or from a water tank, or from a boiler. The water conveyed by the water supply pipe 104 to the heat exchanger 105 may be of any temperature below a typical temperature of water entering the heat exchanger via the first drain pipe 103. For example, the temperature of water entering the heat exchanger 105 via the first drain pipe 103 may be a little less than the temperature of the water emitted from the showerhead 101. For a typical user, the temperature of the water emitted from the showerhead may be selected to be approximately 40° C.

The heat exchanger 105 may have any suitable configuration for exchanging heat, in use, between waste water entering the heat exchanger 105 via the first drain pipe 103 and supply water entering the heat exchanger 105 via the water supply pipe 104, without having the waste water and supply water come into fluid contact. For example, the heat exchanger 105 may be a shell and tube heat exchanger, or it may be a parallel flow heat exchanger, or it may be a counter flow heat exchanger or it may be a double pipe heat exchanger.

The second drain pipe 106 may lead to a water disposal system, for example, by being connected to a sewage system. In implementations, the second drain pipe 106 may lead to a further heat exchanger.

The thermal battery 108 may be any suitable thermal battery configured to heat water. For example, the thermal battery 108 may be a phase change material thermal battery. The thermal battery may be an encapsulated thermal battery. The thermal battery 108 may be operable to heat water flowing through it. The thermal battery 108 may contain multiple paths for water to take through it to control the time that water takes to flow through it. The thermal battery 108 may comprise a heating element. The heating element may be a low power heating element.

In implementations, by operating the heating element at off-peak times, the cost of hot water delivery for the user may be reduced. The heating element may be controllable or programmable to operate whenever required, at off-peak times and/or other times when electricity is relatively cheap. For instance, if the heating element is operably connected to a local source of electricity, e.g. a local renewable electricity source such as one or more solar panels and/or a wind turbine, it may be particularly cost effective to operate the heating element when the local source of electricity is operating, e.g. during daylight hours if the local source of electricity comprises one or more solar panels or when it is windy if the local source of electricity comprises a wind turbine.

In use, water is conveyed by the water supply pipe 104 into the heat exchanger 105. The heat exchanger 105 may comprise a first conduit that conveys the water from the water supply pipe 104 to the pre-heated water supply pipe 107.

The pre-heated water supply pipe 107 conveys water to the thermal battery 108. Water is heated in the thermal battery 108 by exchanging heat with the thermal battery 108.

The water is then conveyed through the thermal battery 108 to the principal stream pipe 109. The principal stream pipe 109 then conveys water to the showerhead 101 which is operable to emit a fluid stream. The temperature of water entering the principal stream pipe 109 from the thermal battery 108 may be controlled by varying the rate of flow of water through the thermal battery 108.

Water emitted from the showerhead 101 is collected by the shower tray 102, whereupon it flows into the waste connected to the first drain pipe 103. The first drain pipe 103 conveys this water to the heat exchanger 105. The heat exchanger may comprise a second conduit that conveys water from the first drain pipe 103 to the second drain pipe 106.

In the heat exchanger 105, the first conduit and the second conduit are arranged such that, in use, the water flowing through the second conduit and the water flowing through the first conduit are in a heat exchanging relationship. The water in the second conduit, i.e. the water that has been conveyed into the heat exchanger by the first drain pipe 103, is typically at a higher temperature than the water in the first conduit, i.e. the water that has been conveyed into the heat exchanger 105 by the water supply pipe 104. The heat exchange between the water in the first and second conduits is such that the temperature of water in the first conduit is increased and the temperature of water in the second conduit is decreased. This has the effect of utilising the heat energy of waste-water to heat water from the water supply pipe 104.

FIG. 2 shows a schematic view of another example of a plumbing system 200.

A showerhead 201 is attached to a wall 210, the showerhead 201 being operable to emit water towards a shower tray 202. The shower tray 202 is configured to collect water emitted from the showerhead 201. The shower tray 202 comprises a waste which is connected to a first drain pipe 203.

The first drain pipe 203 leads to a heat exchanger 205. The water which flows into the heat exchanger 205 via the first drain pipe 203 exits the heat exchanger 205 via a second drain pipe 206.

A water supply pipe 204 is connected to the heat exchanger 205. The water which flows into the heat exchanger 205 via the water supply pipe 204 exits the heat exchanger 205 via a pre-heated water supply pipe 207.

A cold water supply pipe 209 is connected at a first end to the water supply pipe 204 and at a second end to a mixer 211. The first end of the cold water supply pipe 209 is connected to the water supply pipe 204 at a location upstream of the heat exchanger 205. At least one valve may be present at the connection between the cold water supply pipe 209 and the water supply pipe 204, the valve(s) being operable to control flow into the heat exchanger 205 via the water supply pipe 204 and into the cold water supply pipe 209 from the water supply pipe 204.

The pre-heated water supply pipe 207 is connected at a first end to the heat exchanger 205 and at a second end to a thermal battery 208.

A hot water supply pipe 213 is connected at a first end to the thermal battery 208 and at a second end to the mixer 211.

A principal stream pipe 212 is connected at a first end to the mixer 211 and at a second end to the showerhead 201. The principal stream pipe 212 may be connected directly or indirectly to the showerhead 201.

The showerhead 201 is shown in FIG. 2 to be connected to the wall 210, but it could equally be connected to any surface in the ablutionary setting, for example, the ceiling or the floor if so desired. Implementations may include a plurality of showerheads. The showerhead 201 may be operable by a user to control its flow. Any device for emitting water may be employed in place of the showerhead.

In use, the shower tray 202 collects water emitted by the showerhead 201, but it is appreciated that it need not be a shower tray, for example a bathtub or a portion of the floor of a wet room or part thereof comprising a waste connected to the first drain pipe 203 could replace the shower tray 202. Any receptacle capable of collecting water emitted by the showerhead 201 and comprising a waste connected to the first drain pipe 203 could work in place of the shower tray 202. The shower tray 202 may comprise a plurality of wastes connected such that their combined flow enters the first drain pipe 203.

The water supply pipe 204 may convey water from any suitable water source to the heat exchanger 205. For example, it may convey water from a mains water supply, or from a water tank, or from a boiler. The water conveyed by the water supply pipe 204 to the heat exchanger 205 may be of any temperature below a typical temperature of water entering the heat exchanger via the first drain pipe 203. For example, the temperature of water entering the heat exchanger 205 via the first drain pipe 203 may be a little less than the temperature of the water emitted from the showerhead 201. For a typical user, the temperature of the water emitted from the showerhead may be selected to be approximately 40° C.

The heat exchanger 205 may have any suitable configuration for exchanging heat, in use, between waste water entering the heat exchanger 205 via the first drain pipe 203 and supply water entering the heat exchanger 205 via the water supply pipe 204, without having the waste water and supply water come into fluid contact. For example, the heat exchanger 205 may be a shell and tube heat exchanger, or it may be a parallel flow heat exchanger, or it may be a counter flow heat exchanger or it may be a double pipe heat exchanger.

The second drain pipe 206 may lead to a water disposal system, for example, by being connected to a sewage system. In implementations, the second drain pipe 206 may lead to a further heat exchanger.

The thermal battery 208 may be any suitable thermal battery configured to heat water. For example, the thermal battery 208 may be a phase change material thermal battery. The thermal battery may be an encapsulated thermal battery. The thermal battery 208 may be operable to heat water flowing through it. The thermal battery 208 may contain multiple paths for water to take through it to control the time that water takes to flow through it. The thermal battery 208 may comprise a heating element. The heating element may be a low power heating element.

In implementations, by operating the heating element at off-peak times, the cost of hot water delivery for the user may be reduced. The heating element may be controllable or programmable to operate whenever required, at off-peak times and/or other times when electricity is relatively cheap. For instance, if the heating element is operably connected to a local source of electricity, e.g. a local renewable electricity source such as one or more solar panels and/or a wind turbine, it may be particularly cost effective to operate the heating element when the local source of electricity is operating, e.g. during daylight hours if the local source of electricity comprises one or more solar panels or when it is windy if the local source of electricity comprises a wind turbine.

The mixer 211 may comprise a mixer valve such as a digital mixer valve. The mixer valve may be a thermostatic valve. The mixer 211 operates to mix flows received from the cold water supply pipe 209 and the hot water supply pipe 213 to produce a principal stream of water having a desired temperature that then flows along the principal stream pipe 212 towards the showerhead 201.

In use, water is conveyed by the water supply pipe 204 into the heat exchanger 205. The heat exchanger 205 may comprise a first conduit that conveys the water from water supply pipe 204 to the pre-heated water supply pipe 207.

Water may also be conveyed, in use, by the cold water supply pipe 209 to the mixer 211.

The pre-heated water supply pipe 207 conveys water to the thermal battery 208. Water is heated in the thermal battery 208 by exchanging heat with the thermal battery 208.

Water heated by the thermal battery 208 is then conveyed by the hot water supply pipe 213 from the thermal battery 208 to the mixer 211. Water from the cold water supply pipe 209 and water from the hot water supply pipe 213 is mixed in the mixer 211 to achieve a desired temperature. This temperature may be varied, in use, by adjustment of the mixer 211.

Water at the desired temperature is then conveyed from the mixer 211 by the principal stream pipe 212 towards the showerhead 201.

Water emitted from the showerhead 201 is collected by the shower tray 202, whereupon it flows into the waste connected to the first drain pipe 203. The first drain pipe 203 conveys this water to the heat exchanger 205. The heat exchanger 205 may comprise a second conduit that conveys water from the first drain pipe 203 to the second drain pipe 206.

In the heat exchanger 205, the first conduit and the second conduit are arranged such that, in use, the water flowing through the second conduit and the water flowing through the first conduit are in a heat exchanging relationship. The water in the second conduit, i.e. the water that has been conveyed into the heat exchanger 205 by the first drain pipe 203, is typically at a higher temperature than the water in the first conduit, i.e. the water that has been conveyed into the heat exchanger 205 by the water supply pipe 204. The heat exchange between the water in the first and second conduits is such that the temperature of water in the first conduit is increased and the temperature of water in the second conduit is decreased. This has the effect of utilising the heat energy of waste-water to heat water from the water supply pipe 204.

FIG. 3 shows a schematic view of another example of a plumbing system 300.

A showerhead 301 is attached to a wall 310, the showerhead 301 being operable to emit water towards a shower tray 302. The shower tray 302 is configured to collect water emitted from the showerhead 301. The shower tray 302 comprises a waste which is connected to a first drain pipe 303.

The first drain pipe 303 leads to a heat exchanger 305. The water which flows into the heat exchanger 305 via the first drain pipe 303 exits the heat exchanger 305 via a second drain pipe 306.

A water supply pipe 304 is connected to the heat exchanger 305. The water which flows into the heat exchanger 305 via the water supply pipe 304 exits the heat exchanger 305 via a first pre-heated water supply pipe 309.

The first pre-heated water supply pipe 309 is connected to the heat exchanger 305 at a first end and to a mixer 311 at a second end.

A second pre-heated water supply pipe 307 is connected to the first pre-heated water supply pipe 309 at a first end and to a thermal battery 308 at a second end. The junction where the second pre-heated water supply pipe 307 meets the first pre-heated water supply pipe 309 may comprise a valve. The valve may be operable to control the flow of water at the junction.

A hot water supply pipe 313 is connected at a first end to the thermal battery 308 and at a second end to the mixer 311.

A principal stream pipe 312 is connected at a first end to the mixer 311 and at a second end to the showerhead 301. The second end of the principal stream pipe 312 may be connected directly or indirectly to the showerhead 301.

The showerhead 301 is shown in FIG. 3 to be connected to the wall 310 of the ablutionary setting, but it is appreciated by the skilled person that it could equally be connected to any surface in the ablutionary setting, for example, the ceiling or the floor if so desired. There may be a plurality of showerheads. The showerhead 301 may be operable by a user to control its flow. Any device for emitting water may be employed in place of the showerhead.

In use, the shower tray 302 collects water emitted by the showerhead 301, but it is appreciated that it need not be a shower tray. For example, a bathtub or a portion of the floor of a wet room or part thereof comprising a waste connected to the first drain pipe 303 could replace the shower tray 302. Any receptacle capable of collecting water emitted by the showerhead 301 and comprising a waste connected to the first drain pipe 303 could work in place of the shower tray 302. The shower tray 302 may comprise a plurality of wastes connected such that their combined flow enters the first drain pipe 303.

The water supply pipe 304 may convey water from any suitable water source to the heat exchanger 305. For example, it may convey water from a mains water supply, or from a water tank, or from a boiler. The water conveyed by the water supply pipe 304 to the heat exchanger 305 may be of any temperature below a typical temperature of water entering the heat exchanger 305 via the first drain pipe 303. For example, the temperature of water entering the heat exchanger 305 via the first drain pipe 303 may be a little less than the temperature of the water emitted from the showerhead 301. For a typical user, the temperature of the water emitted from the showerhead may be selected to be approximately 40° C.

The heat exchanger 305 may have any suitable configuration for exchanging heat, in use, between waste water entering the heat exchanger 305 via the first drain pipe 303 and supply water entering the heat exchanger via the water supply pipe 304, without having the waste water and supply water come into fluid contact. For example, the heat exchanger 305 may be a shell and tube heat exchanger, or it may be a parallel flow heat exchanger, or it may be a counter flow heat exchanger or it may be a double pipe heat exchanger.

The second drain pipe 306 may lead to a water disposal system, for example, by being connected to a sewage system. In implementations, the second drain pipe 306 may lead to a further heat exchanger.

The thermal battery 308 may be any suitable thermal battery configured to heat water. For example, the thermal battery 308 may be a phase change material thermal battery. The thermal battery may be an encapsulated thermal battery. The thermal battery 308 may be operable to heat water flowing through it. The thermal battery 308 may contain multiple paths for water to take through it to control the time that water takes to flow through it. The thermal battery 308 may comprise a heating element. The heating element may be a low power heating element.

In implementations, by operating the heating element at off-peak times, the cost of hot water delivery for the user may be reduced. The heating element may be controllable or programmable to operate whenever required, at off-peak times and/or other times when electricity is relatively cheap. For instance, if the heating element is operably connected to a local source of electricity, e.g. a local renewable electricity source such as one or more solar panels and/or a wind turbine, it may be particularly cost effective to operate the heating element when the local source of electricity is operating, e.g. during daylight hours if the local source of electricity comprises one or more solar panels or when it is windy if the local source of electricity comprises a wind turbine.

The mixer 311 may comprise a mixer valve such as a digital mixer valve. The mixer valve may be a thermostatic valve. The mixer 311 operates to mix flows received from the first pre-heated water supply pipe 309 and the hot water supply pipe 313 to produce a principal stream of water having a desired temperature that then flows along the principal stream pipe 312 towards the showerhead 301.

In use, water is conveyed by the water supply pipe 304 into the heat exchanger 305. The heat exchanger 305 may comprise a first conduit that conveys the water from the water supply pipe 304 to the first pre-heated water supply pipe 309.

The water flowing in the first pre-heated water supply pipe 309 is split at the junction where the first pre-heated water supply pipe 309 meets the second pre-heated water supply pipe 307.

The water flowing through the second pre-heated water supply pipe 307 is conveyed to the thermal battery 307 whereupon it is heated. The water flowing through the first pre-heated water supply pipe 309 is conveyed to the mixer 311.

Water heated by the thermal battery 308 is then conveyed by the hot water supply pipe 313 from the thermal battery 308 to the mixer 311. Water from the first pre-heated water supply pipe 309 and water from the hot water supply pipe 313 is mixed in the mixer 311 to achieve a desired temperature. This temperature may be configurable in use by adjustment of the mixer 311.

Water at the desired temperature is then conveyed from the mixer 311 by principal stream pipe 312 towards the showerhead 301.

Water emitted from the showerhead 301 is collected by the shower tray 302, whereupon it flows into the waste connected to the first drain pipe 303. The first drain pipe 303 conveys this water to the heat exchanger 305. The heat exchanger 305 may comprise a second conduit that conveys water from the first drain pipe 303 to the second drain pipe 306.

In the heat exchanger 305, the first conduit and the second conduit are arranged such that, in use, the water flowing through the second conduit and the water flowing through the first conduit are in a heat exchanging relationship. The water in the second conduit, i.e. the water that has been conveyed into the heat exchanger 305 by the first drain pipe 303, is typically at a higher temperature than the water in the first conduit, i.e. the water that has been conveyed into the heat exchanger 305 by the water supply pipe 304. The heat exchange between the water in the first and second conduits is such that the temperature of water in the first conduit is increased and the temperature of water in the second conduit is decreased. This has the effect of utilising the heat energy of waste-water to heat water from the water supply pipe 304.

FIG. 4 shows a schematic view of another example of a plumbing system 400.

A showerhead 401 is attached to a wall 410, the showerhead 401 being operable to emit water towards a shower tray 402. The shower tray 402 is configured to collect water emitted from the showerhead 401. The shower tray 402 comprises a waste to which is connected a first drain pipe 403.

The first drain pipe 403 is connected at a first end to the waste of the shower tray 402 and at a second end to a third drain pipe 415. The combined flow of the first drain pipe 403 and the third drain pipe 415 flows into a heat exchanger 405. The water which flows into the heat exchanger 405 via the combined flow of the first drain pipe 403 and the third drain pipe 415 exits the heat exchanger 405 via a second drain pipe 406.

A water supply pipe 404 is connected to the heat exchanger 405. The water which flows into the heat exchanger 405 via the water supply pipe 404 exits the heat exchanger 405 via a first pre-heated water supply pipe 409.

The first preheated water supply pipe 409 is connected to the heat exchanger 405 at a first end and to a mixer 411 at a second end.

A second pre-heated water supply pipe 407 is connected to the first pre-heated water supply pipe 409 at a first end and to a thermal battery 408 at a second end. The junction where the second pre-heated water supply pipe 407 meets the first pre-heated water supply pipe 409 may comprise a valve (not shown). The valve may be operable to control the flow of water at the junction. The second pre-heated water supply pipe 407 is connected to first pre-heated water supply pipe 409 between the at a point between first and second ends of the first pre-heated water supply pipe 409.

A hot water supply pipe 416 is connected at a first end to the thermal battery 408 and at a second end to the mixer 411.

A first principal stream pipe 412 is connected at a first end to the mixer 411 and at a second end to the showerhead 401.

A sink 414 comprises a faucet 416 connected to a second principal stream pipe 413, the faucet 416 being operable to emit water. The sink 414 also comprises a receptacle, for example a sink bowl, which is arranged to collect the water emitted by the faucet 416. The sink bowl further comprises a waste which is connected to the third drain pipe 415.

The second principal stream pipe 413 is connected at a first end to the first principal stream pipe 412 and at a second end to the faucet 416. The second principal stream pipe 413 is connected to the first principal stream pipe 412 at a point between the first and second ends of the first principal stream pipe 412. A valve (not shown) may be present at the junction where the second principal stream pipe 413 is connected to the first principal stream pipe 412. The valve may be operable to control the flow of water at the junction.

The third drain pipe 415 is connected at a first end to the waste of the sink bowl and at a second end to the heat exchanger 405.

The showerhead 401 is shown in FIG. 5 to be connected to the wall 410, but it will be appreciated by the skilled person that it could equally be connected to any surface in the ablutionary setting, for example, the ceiling or the floor if so desired. There may be a plurality of showerheads. The showerhead 401 may be operable by a user to control its flow. Any device suitable for emitting water may be employed in place of the showerhead.

The shower tray 402 acts a receptacle for water emitted by the showerhead 401, but it is appreciated that it need not be a shower tray, for example a bathtub or a portion of the floor of a wet room or part thereof comprising a waste connected to the first drain pipe 403 could replace the shower tray 402. Any receptacle capable of collecting water emitted by the showerhead 401 and comprising a waste connected to the first drain pipe 403 could work in place of the shower tray 402. The shower tray 402 may comprise a plurality of wastes connected such that their combined flow enters the first drain pipe 403.

The water supply pipe 404 may convey water from any suitable water source to the heat exchanger 405. For example, it may convey water from a mains water supply, or from a water tank, or from a boiler. The water conveyed by the water supply pipe 404 to the heat exchanger 405 may be of any temperature below a typical temperature of water entering the heat exchanger 405 via the combined flow of the first drain pipe 403 and the third drain pipe 415. For example, the temperature of water entering the heat exchanger 405 via the combined flow of the first drain pipe 403 and the third drain pipe 415 may be a little less than the temperature of the water emitted from the showerhead 401 and/or the faucet 416. For a typical user, the temperature of the water emitted from the showerhead 401 and/or the faucet 416 may be selected to be approximately 40° C.

The heat exchanger 405 may have any suitable configuration for exchanging heat between waste water entering the heat exchanger 405 via the combined flow of the first drain pipe 403 and the third drain pipe 415 and supply water entering the heat exchanger 405 via the water supply pipe 404, without having the waste water and supply water come into fluid contact. For example, the heat exchanger 405 may be a shell and tube heat exchanger, or it may be a parallel flow heat exchanger, or it may be a counter flow heat exchanger or it may be a double pipe heat exchanger.

The second drain pipe 406 may lead to a water disposal system, for example, by being connected to a sewage system. The second drain pipe 406 may lead to a further heat exchanger.

The thermal battery 408 may be any suitable thermal battery configured to heat water. For example, the thermal battery 408 may be a phase change material thermal battery. The thermal battery may be an encapsulated thermal battery. The thermal battery 408 may be operable to heat water flowing through it. The thermal battery 408 may contain multiple paths for water to take through it to control the time that water takes to flow through it. The thermal battery 408 may comprise a heating element. The heating element may be a low power heating element.

In implementations, by operating the heating element at off-peak times, the cost of hot water delivery for the user may be reduced. The heating element may be controllable or programmable to operate whenever required, at off-peak times and/or other times when electricity is relatively cheap. For instance, if the heating element is operably connected to a local source of electricity, e.g. a local renewable electricity source such as one or more solar panels and/or a wind turbine, it may be particularly cost effective to operate the heating element when the local source of electricity is operating, e.g. during daylight hours if the local source of electricity comprises one or more solar panels or when it is windy if the local source of electricity comprises a wind turbine.

The mixer 411 may comprise a mixer valve such as a digital mixer valve. The mixer valve may be a thermostatic valve. The mixer 411 operates to mix flows received from the first pre-heated water supply pipe 409 and the hot water supply pipe 416 to produce a principal stream of water having a desired temperature that then flows into the first principal stream pipe 412 towards the showerhead 401.

In use, water is conveyed by the water supply pipe 404 into the heat exchanger 405. The heat exchanger 405 may comprise a first conduit that conveys the water from the water supply pipe 404 to the first pre-heated water supply pipe 409.

The water flowing in the first pre-heated water supply pipe 409 is split at the junction between the first pre-heated water supply pipe 409 and the second pre-heated water supply pipe 407.

The water flowing through the second pre-heated water supply pipe 407 is conveyed to the thermal battery 408, whereupon it is heated. The water flowing through the first pre-heated water supply pipe 409 is conveyed to the mixer 411.

Water heated by the thermal battery 408 is then conveyed by the hot water supply pipe 416 from the thermal battery 408 to the mixer 411. Water from the first pre-heated water supply pipe 409 and water from the hot water supply pipe 416 is mixed in the mixer 411 to achieve a desired temperature. The desired temperature may be selectable, in use, by adjustment of the mixer 311.

Water at the desired temperature is then conveyed from the mixer 411 by the first principal stream pipe 412. At the junction where the second principal stream pipe 413 meets the first principal stream pipe 412, the flow of water may be split. A first portion of water may flow to the showerhead 401. A second portion of water may flow through the second principal stream pipe 413 to the faucet 416. The faucet 416 emits water conveyed to it by the second principal stream pipe 413 towards the sink bowl whereupon it is collected by the sink bowl and flows into the waste connected to the third drain pipe 415.

Water emitted from the showerhead 401 is collected by the shower tray 402, whereupon it flows into the waste connected to the first drain pipe 403. The water flowing in the first drain pipe 403 and the water flowing in the third drain pipe 415 is combined at the junction where the first drain pipe 403 connects to the third drain pipe 415. The combined water flow of water flowing in the first drain pipe 403 and the third drain pipe 415 then flows into the heat exchanger 405.

The heat exchanger 405 may comprise a second conduit that conveys the combined water flow of water flowing in the first drain pipe 403 and the third drain pipe 415 to the second drain pipe 406.

In the heat exchanger 405, the first conduit and the second conduit are arranged such that, in use, the water flowing through the second conduit and the water flowing through the first conduit are in a heat exchanging relationship. The water in the second conduit, i.e. the combined water flow of water flowing in the first drain pipe 403 and the third drain pipe 415, is at a higher temperature than the water in the first conduit, i.e. the water that has been conveyed into the heat exchanger 405 by the water supply pipe 404. The heat exchange between the water in the first and second conduits is such that the temperature of water in the first conduit is increased and the temperature of water in the second conduit is decreased. This has the effect of utilising the heat energy of waste-water to heat water from the water supply pipe 404.

FIG. 5 shows a schematic representation of a method 500 for using a plumbing or ablutionary system. The plumbing system may be any plumbing system according to the present disclosure, e.g. one of the example plumbing systems 100, 200, 300, 400 described herein.

In a first step 501, the or a thermal battery is charged to a predetermined energy level. The thermal battery may be charged during off-peak energy usage times. The thermal battery may be charged using off-grid electricity. The thermal battery may be charged using renewable forms of electricity such as solar power, wind power or geothermal power. The thermal battery may be charged using a heat pump.

In a second step 502, the or a mixing device configured to receive at least one water supply stream and operable to provide at least one principal stream at a controlled temperature provides at least one principal stream at a controlled temperature, said stream being emitted by the or a at least one fluid delivery device. One or more of the fluid delivery devices may be a showerhead or any suitable fluid delivery device.

In a third step 503, the water emitted by the fluid delivery device(s) is collected by at least one receptacle and the water collected by the at least one receptacle enters a drain.

In a fourth step 504, the water entering the drain comprising the at least one receptacle enters the or a heat exchange apparatus.

In a fifth step 505, the water entering the heat exchange apparatus from the drain exchanges heat with supply water that enters the heat exchange apparatus without the supply water and waste water from the drain coming into fluid contact, thereby recovering heat energy from the waste water and using it to heat the supply water.

In a sixth step 506, the supply water heated by the heat exchanger is conveyed to the mixing device.

The second step 502, the third step 503, the fourth step 504, the fifth step 505, and the sixth step 506 may be repeated, in use, as long as is desired, or until the thermal battery is depleted of energy. When the thermal battery is depleted of energy, the first step 501 needs to be repeated before the second step 502 and subsequent steps can be performed.

The illustrations of the examples described herein are intended to provide a general understanding of the structure of the various examples. The illustrations are not intended to serve as a complete description of all the elements and features of apparatus and systems that utilise the structures or methods described herein. Many other examples may be apparent to those of skill in the art upon reviewing the disclosure. Additionally, the illustrations are merely representational and may not be drawn to scale. Certain proportions within the illustrations may be exaggerated, while other proportions may be minimised. Accordingly, the disclosure and figures are to be regarded as illustrative rather than restrictive.

While this specification contains many specifics, these should not be construed as limitations on the scope of the invention or of what may be claimed, but rather as a description of features specific to particular implementations. Certain features that are described in this specification in the context of separate examples can also be implemented in combination in a single example. Conversely, various features that are described in the context of a single example can also be implemented in multiple examples separately or in any suitable sub-combination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excides from the combination, and the claimed combination may be directed to a sub-combination or variation of a sub-combination.

This disclosure is intended to cover any and all subsequent adaptations or variations of various examples. Combinations of the above examples, and other examples not specifically described herein, should be apparent to those of skill in the art upon reviewing the description.

It is intended that the foregoing detailed description be regarded as illustrative rather than limiting and it is understood that the following claims including all equivalents are intended to define the scope of the invention. The claims should not be read as limited to the described order or elements unless stated to that effect. Therefore, all examples that come within the scope and spirit of the following claims and equivalents thereto are claimed as the invention.

It will be understood that the invention is not limited to the embodiments described above. Various modifications and improvements can be made without departing from the concepts disclosed herein. Except where mutually exclusive, any of the features may be employed separately or in combination with any other features and the disclosure extends to all combinations and sub-combinations of any one or more features disclosed herein.