Wastewater Heat Pump System

This application claims priority to U.S. Provisional Application No. 63/650,013, filed May 21, 2024, the entire disclosure of which is hereby incorporated herein by reference.

The present disclosure relates generally to the field of shower systems and, more particularly, to a shower system that uses heat from wastewater to heat incoming fresh water.

Existing shower systems and other water distribution systems may dispense water for use by a user. Preferably, the dispensed water is at a comfortable temperature for the user. It may be desirable to provide a mechanism for controlling the temperature of the dispensed water in a cost-effective and/or energy-efficient manner.

While the disclosure is susceptible to various modifications and alternative forms, a specific embodiment thereof is shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the drawings and detailed description presented herein are not intended to limit the disclosure to the particular embodiment disclosed, but to the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims

The present disclosure relates to a water distribution system, e.g., a shower system, that utilizes a heat pump to transfer heat between used water, or “wastewater,” and incoming water, or “fresh water,” that is dispensed by the shower system. The heat pump may include a first heat exchanger, or “fresh water heat exchanger,” receiving fresh water from a fresh water supply and a second heat exchanger, or “wastewater heat exchanger,” receiving wastewater from the water distribution system. A heat transfer fluid, also referred to as a working fluid, circulating through the heat pump between the heat exchangers may transfer heat between the wastewater and the fresh water. For example, the heat transfer fluid may absorb heat, also referred to as thermal energy or heat energy, from the wastewater via the wastewater heat exchanger and reject heat into the fresh water via the fresh water heat exchanger. The heat pump is thereby operable to utilize the wastewater for effectively and efficiently controlling the temperature of the fresh water. The heat pump may provide over 100% efficiency, such as between 300% to 600% efficiency. The fresh water exiting the fresh water heat exchanger may be routed toward an outlet, e.g., a shower head or shower spray, that dispenses the fresh water. The dispensed fresh water may then be used and subsequently collected via a receptacle as wastewater that is then routed toward the wastewater heat exchanger. The wastewater exiting the wastewater heat exchanger may be routed toward a drain or another component for processing the wastewater. This cycle may continue for a portion of or the entirety of a water distribution process, e.g., for a portion of or an entire duration of a showering operation.

The water distribution system may optionally be equipped with additional components utilized in conjunction with the heat pump for controlling the temperature of the fresh water. The additional components may be positioned upstream and/or downstream from the heat pump, e.g., upstream and/or downstream from the fresh water heat exchanger. A mixing valve may be positioned downstream from the heat pump and upstream from the outlet. The mixing valve may receive the fresh water exiting the fresh water heat exchanger and an additional incoming water stream, e.g., a second fresh water stream, from the fresh water supply connected to the heat pump or another fresh water supply. The mixing valve may operate to combine the fresh water exiting the fresh water heat exchanger with the additional incoming water stream to achieve a desirable or target temperature of the fresh water that is dispensed via the outlet. Additionally or alternatively, the water distribution system may include a fresh water storage tank, or hot water tank, positioned between the heat pump and the outlet. Additionally or alternatively, the water distribution system may include a thermal storage device comprising a heat storage material, e.g., a phase change material, positioned between the heat pump and the outlet. The hot water tank and/or the thermal storage device may be utilized alone or in conjunction with the mixing valve. For example, the hot water tank and/or the thermal storage device may be positioned between the fresh water heat exchanger and the mixing valve. The heat pump may be controllable, e.g., via a controller and a user interface, to adjust the temperature of the fresh water exiting the fresh water heat exchanger according to a user input indicative of a desired water temperature and/or a desired temperature setpoint.

Additional features and advantages are provided by the present disclosure, which can be realized by the following detailed description. The figures illustrate exemplary systems involving shower systems by way of example. The present disclosure is not limited to the details or methodology set forth in the description or illustrated in the figures. The terminology used herein is for the purpose of description only and should not be regarded as limiting.

Example embodiments of shower systems that include a heat pump for efficiently recovering heat from wastewater and controlling a temperature of fresh water using the recovered heat will now be described with reference to the drawings. The present disclosure is not limited to shower systems. Aspects of the present disclosure that are depicted in the illustrated embodiments or otherwise described herein may be used in conjunction with other water distribution systems. Water distribution systems encompassed by the present disclosure include, without limitation, water distribution systems that dispense water for consumption and/or washing and water distribution systems used for private, public, domestic, residential, commercial, and/or industrial use. For example, water distribution systems such as, for example and without limitation, showers, baths, washtubs, hot tubs, sinks, fountains, water dispensers, and the like may incorporate aspects of the present disclosure and are encompassed herein. Example water distribution systems may include an outlet dispensing the fresh water that is conditioned via the heat pump. The outlet may include any suitable device that is configured to dispense liquid or water. The outlet may include an ablutionary fitting, such as, for example and without limitation, a showerhead, shower spray, hand shower, faucet, wand, spigot, tap, spout, or the like. The outlet can include a single outlet or more than one outlet. Where the outlet includes multiple, e.g., two or more outlets, the outlets can be similar types of outlets or dissimilar types of outlets. Elements and features described with reference to one illustrated embodiment are not limited to that embodiment only; the features and elements of any one or more of the illustrated embodiments can be utilized in any other embodiment in any combination.

The example embodiments described herein include water distribution systems with various water streams which may flow through various process stages. The present disclosure is not limited to water and may be used with any suitable type of liquid. Accordingly, reference to a water stream or stream of water may encompass other liquid streams or streams of liquid unless expressly stated otherwise or the context clearly indicates otherwise. The phrases “liquid stream,” “stream of liquid,” “water stream,” “stream of water,” and the like refer to a flow of liquid, e.g., water, in a flow direction; a stream or flow of liquid, e.g., water, is not limited to any particular type of flow and may be in a single conduit, distributed in multiple conduits, freely dispersed in a space (e.g., as a spray or droplets), accumulated in one or more vessels, or in another form that allows the stream to flow in the flow direction.

shows a schematic of a water distribution systemincluding a heat pumpoperable to efficiently and effectively control a temperature of a first water stream or a first “fresh water” stream. The heat pumpmay be operable to recover heat, also referred to as thermal energy or heat energy, from a second water stream or “wastewater” stream. The wastewater streamis produced from use of the first water streamin a space. The heat pumpmay transfer the recovered heat to the fresh waterto thereby produce a conditioned fresh water stream, e.g., warm fresh water, that is routed toward an outlet. In this way, the heat pumpmay advantageously provide an energy efficient and effective means for controlling, e.g., raising, the temperature of the conditioned fresh water streambefore it is dispensed and used in the space. The heat pumpmay circulate a working fluid or heat transfer fluid therein and the working fluid is used as a heat transfer medium between the wastewater streamand the first fresh water stream.

The outletmay dispense a fresh water streaminto the space. The dispensed fresh water streammay include the conditioned fresh water streamfrom the heat pump. The dispensed fresh water streamcan be used by a user in the space, e.g., for showering, bathing, washing, etc. The wastewater streammay be produced as a result. The wastewater streamis understood to include water that is dispensed into the spaceand collected within and/or downstream from the space; the wastewater streammay be produced irrespective of the dispensed fresh water streambeing used by a user. The wastewater streammay flow toward and through the heat pump, where heat may be transferred to the first fresh water streamand the cycle continues. This cycle may continue for a portion, or the entirety, of a water distribution process performed by the system, e.g., a showering operation.

The conditioned fresh water streammay flow directly toward and be dispensed by the outlet. As such, the characteristics of the dispensed fresh water stream, e.g., temperature, may be substantially similar to the characteristics of the conditioned fresh water streamexiting the heat pump.

The water distribution systemmay be a shower system, which may be located indoors or outdoors. The outletmay be or may include a shower outlet, e.g., a shower head, spray head, nozzle, hand shower, etc., that dispenses water into a shower space. Additionally or alternatively, the water distribution systemmay be another type of system that dispenses fresh water to the spacevia the outlet, and may include any suitable type of outlet device, unit, module, or component configured to dispense water. For example, the water distribution systemmay include, for example and without limitation, a shower system, a bath, a washtub, a hot tub, a sink, a fountain, a water dispenser, and/or the like. The outletmay include an ablutionary fitting, such as, for example and without limitation, a showerhead, shower spray, hand shower, faucet, wand, spigot, tap, spout, or the like. The outletcan include a single outlet or more than one outlet. Where the outletincludes multiple, e.g., two or more outlets, the outlets can be similar types of outlets or dissimilar types of outlets. For example, the outletmay include a single ablutionary fitting or multiple of the same and/or different types of ablutionary fittings. The spacemay include a shower space or may include any other type of space adapted to receive water from the outletsuch as a bathroom space, a kitchen space, an outdoor space, a sink space, a water dispenser space, a fountain space, a tub space, etc.

The water distribution systemmay include a receptaclepositioned relative to the outletfor collecting the wastewater stream. For example, the receptaclemay be positioned below the outlet. The receptaclemay include any suitable configuration to collect the wastewater stream. For example, where the water distribution systemis a shower system, the receptaclemay include a shower tray, shower base, washbasin, bathtub, etc. The receptaclemay additionally or alternatively include a floor, such as a bathroom floor, kitchen floor, outdoor floor, etc., a vessel, a bowl, a basin, a tub, a pan, a drip tray, a fountain basin, and/or a surface that may become wet from and/or collect the dispensed fresh water streamand the wastewater stream.

The receptaclemay include one or more access points, e.g., drain holes or openings, defined or integrated in the receptacle. The access pointsmay be positioned at any suitable location of the receptacle, such as a center or periphery of the receptacle. The one or more access pointsmay be configured such that the wastewater streamcollected from the dispensed water streamin the spacemay flow through the access pointsduring use of the systemand into one or more wastewater conduits. The one or more wastewater conduitsmay connect the one or more access pointswith the heat pumpand direct the wastewater streamtoward the heat pump. The receptaclemay include a cover, not illustrated, that can selectively cover the one or more access points.

The receptaclemay be configured, e.g., shaped, to direct or funnel the wastewater streamtoward and into the access points. For example, the receptaclemay be angled, slanted, tilted, bowl-shaped, curved, or the like, such that a natural flow of water may flow directionally across the receptacletoward and into the one or more access points.

One or more screens, not illustrated, may be coupled with or positioned relative to the receptacle to catch or otherwise prevent debris from collecting within the receptacle and entering the access points. In this way, debris may be limited or prevented from entering into water lines, pumps, valves, etc. via the access points. The one or more screens may be coupled adjacent, to or within the one or more access pointsto catch or otherwise prevent debris from flowing through the water distribution system.

The one or more wastewater conduitsdirect the wastewater streamtoward the heat pump. The heat pumpmay transfer heat with the wastewater streamtherein. For example, the heat pumpmay absorb residual heat from the wastewater stream, e.g., into a working fluid circulating in the heat pump. The temperature of the wastewater streammay be lowered via the heat pump. The wastewater streammay exit the heat pumpas a drain stream, which may be at a lower temperature than the wastewater stream. The drain streammay exit the heat pumpinto one or more drain conduits. The one or more drain conduitsmay direct the drain streamtoward a drain. Additionally or alternatively, the drain streammay be recycled or recirculated within the water distribution systemand may be referred to as a recirculation stream or a recycled stream.

Concurrently, or nearly concurrently, the first fresh water streammay be supplied via a fresh water supplyand directed toward the heat pumpvia one or more fresh water conduits. The heat pumpmay transfer heat with the first fresh water streamtherein. For example, the heat pumpmay reject the heat absorbed from the wastewatervia the working fluid into the first fresh water stream. The temperature of the first fresh water streammay be raised via the heat pump, thereby producing the conditioned fresh water streamhaving a higher temperature than the first stream. The conditioned fresh water streammay exit the heat pumpinto one or more outlet conduits. The one or more outlet conduitsmay direct the conditioned fresh water streamtoward the outlet.

The heat pumpmay operate to absorb residual heat from the wastewater streamvia the working fluid circulating in the heat pumpand reject that heat into the first fresh water stream. Through work performed on the working fluid via the heat pump, e.g., a vapor compression cycle, the heat pumpmay condition, e.g., heat, the first fresh water streamat an efficiency over 100%, such as between 300% to 600%. In this way, the heat pumpmay provide improve heat transfer efficiency between the wastewater streamand the first fresh water streamrelative to relying on passive or spontaneous heat transfer between the streams,. Utilizing residual or remaining heat energy from warmer wastewater may aid in the overall efficiency of the heat pump. This may enable water distribution systems like the system, such as electrical shower systems, to use less energy and reduce water consumption. Utilizing an effective warm wastewater boost for the heat pumpmay facilitate using about a third of the energy as compared to systems that use passive heat transfer.

Depending on the desired conditions of the system, the heat transfer direction between the first fresh water streamand the wastewater streamcould be reversed. For example, the heat pumpmay reverse a flow direction of the working fluid therein such that heat is absorbed from the first fresh water streamand heat is rejected into the wastewater stream. The heat pumpmay operate to absorb heat from the first fresh water streamto lower the temperature of the conditioned fresh water stream. Operating the heat pumpto lower the temperature of the conditioned fresh water streammay be implemented in applications where a cold or chilled water stream is dispensed via the outlet, such as in ice showers, ice baths, or applications where cold or chilled water is dispensed for consumption.

The systemmay include one or more fluid motive devices, e.g., pumps, that are operable to move one or more of the first fresh water stream, the wastewater stream, the conditioned fresh water stream, and/or the drain streamthrough the system. For example, the systemmay include a fluid motive device operable to move the first fresh water streamtoward and through the heat pumpand/or the conditioned fresh water streamfrom the heat pumptoward the outlet. Additionally or alternatively, the systemmay include a fluid motive device operable to move the wastewater streamtoward and through the heat pumpand/or the drain streamfrom the heat pumptoward the drainor a recirculation/recycle path.

The systemmay include one or more controllersconnected with the heat pumpand a user interface or UIthat enables a user to adjust the temperature of the conditioned fresh water stream. The controller(s)can be centralized and/or decentralized. One or more of the controller(s)may be dedicated to the heat pumpand connected with the user interface. Electrical connection between the heat pump, the controller(s), and the user interfacemay be established via a wired connection and/or a wireless connection such as via Wi-Fi, Li-Fi, Bluetooth, cellular, or another wireless interface.

The one or more controllersmay be operable to control one or more operating parameters of the heat pumpbased on, or in response to, a user input received via the user interface. The user input may be indicative of a desired temperature of the dispensed fresh water streamin the space. Additionally or alternatively, the controller(s)may be operable to control one or more operating parameters of the heat pumpbased on or according to a temperature setpoint of the dispensed fresh water streamand/or the conditioned fresh water stream, which may be set or dynamically adjusted according to a user input, according to stored user preferences, according to a pre-programmed routine, etc. The operating parameter(s) of the heat pumpcontrolled via the controller(s)may control or adjust a temperature of the conditioned fresh water stream, for example, by controlling or adjusting the heat transfer capability of heat pump. The operating parameter(s) of the heat pumpmay include, for example and without limitation, a flow rate and/or pressure of the working fluid circulating in the heat pump, a temperature of the working fluid circulating in the heat pump, a flow rate of the first fresh water streamthrough the heat pump, and/or a flow rate of the wastewater streamthrough the heat pump.

The controller(s)may utilize feedback from sensors positioned within the systemand/or the heat pump. The systemand/or the heat pumpmay include pressure sensors, temperature sensors, flow meters, and/or the like positioned for monitoring various operating parameters of the systemand/or the heat pumpand providing feedback to the controller(s). The sensors may be positioned at any suitable location along a working fluid loop of the heat pumpand/or at any suitable location of any one or more of the conduits of the system, e.g., the conduit(s),,, and/orof the system. The controller(s)may communicate with the sensor(s) using wired and/or wireless connections as described above.

The user interface or UImay be mounted on a support structure adjacent to the space. For example, the user interfacemay be mounted on a side wall of a shower space. The user interfacemay include user input devices for receiving user inputs associated with the conditioned fresh water streamand/or the dispensed fresh water stream. The user interfacemay include manual input devices such as control buttons, knobs, dials, switches, triggers, or any other type of manual input device. Additionally or alternatively, the user interfacemay include a touchscreen display, such as an LED or LCD display, configured to receive user inputs.

The user interfacemay allow the user to control flow rate, pressure, temperature, and/or another characteristic of the conditioned fresh water streamand/or the dispensed fresh water stream. The user interfacemay additionally or alternatively allow the user to initiate, transition between, terminate, or cycle through different operating modes of the systemincluding those described herein. For example, the user interfacemay allow the user to initiate the heat pumpfor conditioning the first fresh water streamand/or control one or more operating parameters of the heat pumpto achieve a desired temperature of the conditioned fresh water streamand/or the dispensed fresh water stream. The user input devices of the user interfacemay be dedicated to a particular control feature. For example, one or more of the user input devices may be dedicated to controlling water temperature, water flow rate, water pressure, type of water spray, the operating mode of the shower system, etc. The controls enabled by the user interfacedescribed herein are provided by way of example and are not an exhaustive list of functions. The user interfacemay be operable to control any desired functions of the systemincluding those described elsewhere herein.

Referring to, the heat pumpmay include a compressor, a first heat exchanger or a fresh water heat exchanger, and a second heat exchanger or a wastewater heat exchanger. The compressor, the fresh water heat exchanger, and the wastewater heat exchangermay each be positioned along a closed loop or circuitin which a working fluid or heat transfer fluid circulates. The working fluid may include a refrigerant, glycol, brine, or another suitable fluid that enables the heat pump to function as described herein. The compressormay be positioned between the fresh water heat exchangerand the wastewater heat exchanger. An expansion devicemay be positioned on the circuitbetween the heat exchangers,and opposite the compressor.

The fresh water heat exchangermay be positioned to receive the first fresh water streamvia the fresh water conduit(s). The fresh water heat exchangermay facilitate transferring heat between the first fresh water streamand the working fluid therein, producing the conditioned fresh water streamthat exits the fresh water heat exchangertoward and into the outlet conduit(s). For example, the fresh water heat exchangermay facilitate rejecting heat from the working fluid into the first fresh water stream, raising the temperature of the conditioned fresh water stream. A fluid motive device, e.g., a pump, may be provided that drives the first fresh water streamtoward and through the fresh water heat exchangerand/or the conditioned fresh water streamfrom the heat exchanger.

The wastewater heat exchangermay be positioned to receive the wastewater streamvia the wastewater conduit(s). The wastewater heat exchangermay facilitate transferring heat between the wastewater streamand the working fluid therein, producing the drain streamthat exits the wastewater heat exchangertoward and into the drain conduit(s). For example, the wastewater heat exchangermay facilitate absorbing heat from the wastewater streaminto the working fluid, lowering the temperature of the drain stream. A fluid motive device, e.g., a pump, may be provided that drives the wastewater streamtoward and through the wastewater heat exchangerand/or the drain streamfrom the heat exchanger.

The heat exchangers,can include any heat exchanger configuration that enables the heat exchangers,to transfer heat as described herein. For example, each of the heat exchangers,can include a coil configuration, a shell-and-tube configuration, and/or a plate-and-frame configuration. While the heat exchangers,are respectively referred to as the “fresh water” and “wastewater” heat exchanger, this is for convenience and conciseness for this example in which the heat exchangers,may operate. The heat exchangers,can each be used to transfer heat between any water stream within the systemand can also be referred to as a “first” heat exchanger and a “second” heat exchanger. The heat exchangers,may also each independently include one heat exchanger or multiple heat exchangers. The heat exchangers,may be utilized as separate units, components, or modules; additionally or alternatively, the heat exchangers,may be integrated with another component of the system. For example, the heat pump, or a component thereof such as the wastewater heat exchanger, may be integrated with the receptacleof.

The compressormay include, for example, a centrifugal compressor, a scroll compressor, a rotary compressor, a piston compressor, an axial compressor, or another suitable compressor. The compressormay pressurize the working fluid, which may raise the temperature of the working fluid and facilitate circulating the working fluid through the circuit.

The expansion devicemay include, for example, an expansion valve, expansion orifice, capillary tube, or the like. The expansion devicemay lower the pressure of the working fluid which can cause the working fluid to at least partially vaporize. In some embodiments, the expansion devicemay be omitted.

In the illustrated example, pressurized working fluid is routed from the compressortoward the fresh water heat exchanger, in which the working fluid rejects heat into the first fresh water streamthereby producing the conditioned fresh water streamhaving a raised temperature. The working fluid then optionally flows through the expansion device, which may lower the pressure of working fluid before it flows toward and through the wastewater heat exchanger. The working fluid absorbs heat from the wastewater streamin the wastewater heat exchanger, thereby lowering the temperature of the drain stream. The heat transfer fluid can then be routed back toward the compressorand the process may repeat.

The heat pumpmay include a reversing valve that can be positioned to reverse the flow direction of the working fluid through the circuit. For example, a reversing valve can be positioned to route the working fluid from the compressortoward the wastewater heat exchanger, in which the working fluid rejects heat into the wastewater stream, thereby raising the temperature of the drain stream. The working fluid may then flow toward the fresh water heat exchanger, and optionally through the expansion device, and the working fluid may absorb heat from the first fresh water streamin the fresh water heat exchanger, thereby lowering the temperature of the conditioned fresh water stream.

depicts another example of a water distribution systemthat may include similar elements and components to the systemof. Like elements and components between the systemand the systemmay be indicated using like reference numerals. For example, the water distribution systemmay include the heat pumpoperable to transfer heat between the first fresh water streamand the wastewater stream, thereby producing the conditioned fresh water streamand the drain stream. Additionally, the water distribution systemmay include a mixing valvethat may operate to further condition the fresh water before it is dispensed via the outletas the fresh water stream. In particular, the mixing valvemay receive a second fresh water streamthat may be utilized to further condition the conditioned fresh water stream, or another fresh water stream, e.g., by raising or lowering the temperature, upstream from the outlet. In this way, the mixing valvemay be operable to achieve a desired temperature of the dispensed fresh water stream.

The mixing valvemay be positioned between the heat pumpand the outlet. The mixing valvemay receive the conditioned fresh water streamand the second fresh water stream. The mixing valvemay combine the conditioned fresh water streamand the second fresh water streamto produce a mixed water streamthat flows through the outlet conduit(s)towards the outlet. The second fresh water streammay be utilized to further condition the conditioned fresh water stream, e.g., by raising or lowering the temperature, upstream from the outlet. The characteristics of the dispensed fresh water stream, e.g., temperature, may be substantially similar to the characteristics of the mixed water streamexiting the mixing valve.

The mixing valvemay include one mixing valve or multiple mixing valves. Although the mixing valveis shown positioned between the heat pumpand the outlet, a mixing valvemay additionally or alternatively be positioned at another location of the systemfor receiving another water stream for combining with the second fresh water stream. For example, a mixing valvemay be positioned for receiving the first fresh water streamand combining the first fresh water streamwith the second fresh water streamupstream from the heat pumpand the outlet. Additionally or alternatively, a mixing valvemay be positioned for receiving the wastewater streamand combining the wastewater streamwith the second fresh water streamupstream from the heat pumpand the outlet.

The conditioned fresh water streammay flow toward the mixing valvevia one or more intermediate conduitsconnected between the heat pumpand the mixing valve. Concurrently, or nearly concurrently, the second fresh water streammay be supplied via a second fresh water supplyand directed toward the mixing valvevia one or more second fresh water conduits. The second fresh water supplymay be or include the fresh water supplyor may be or include a different water supply. The conditioned fresh water streamand the second fresh water streammay be combined or mixed in the mixing valve, whereby the characteristics of the second fresh water streammay influence and further condition the conditioned fresh water stream. In this way, the mixed water streamand the dispensed water streammay be provided with a desirable temperature for the user of the system. For example, a temperature of the second fresh water streamentering the mixing valvemay be lower than a temperature of the conditioned fresh water streamentering the mixing valve. Alternatively, a temperature of the second fresh water streamentering the mixing valvemay be higher than a temperature of the conditioned fresh water streamentering the mixing valve.

The mixing valvemay be controllable to adjust flow of the conditioned fresh water streamand/or the second fresh water stream. For example, the mixing valvemay be controllable to increase and/or decrease flow of the conditioned fresh water streamreceived by the mixing valve. Additionally or alternatively, the mixing valvemay be controllable to increase and/or decrease flow of the second fresh water streamreceived by the mixing valve. Control valve(s) may also be provided upstream from the mixing valve, e.g., on the conduit(s)and/or, for adjusting flow of the water streams,. Adjusting the flow of the conditioned fresh water streamand/or the second fresh water streamentering the mixing valvemay provide greater flexibility and control over the temperature of the mixed water streamexiting the mixing valve. The flow of the water streamsand/ormay be controlled manually and/or via the controller(s). The flow of the conditioned fresh water streamand/or the second fresh water streammay be controlled via the controller(s)based on, or in response to, a user input indicative of a desired temperature of the dispensed fresh water streamin the space. The user input may be received via the user interface. Additionally or alternatively, the controller(s)may be operable to control flow of the water streamsand/orbased on or according to a temperature setpoint of the dispensed fresh water streamand/or the mixed water stream, which may be set or dynamically adjusted according to a user input, according to stored user preferences, according to a pre-programmed routine, etc. The flow of the water streamsand/ormay be controlled in conjunction with or in the alternative to the control operations of the heat pumpdescribed above.

depicts another example of a water distribution systemthat may include similar components to the systemofand/or the systemof. Like elements and components between the systemand/orand the systemmay be indicated using like reference numerals. For example, the water distribution systemmay include the heat pumpoperable to transfer heat between the first fresh water streamand the wastewater stream, thereby producing the conditioned fresh water streamand the drain stream. The water distribution systemmay also include the mixing valvethat may operate to further condition the fresh water before it is dispensed via the outletas the fresh water stream. Additionally, the water distribution systemmay include a storage tank, e.g., a hot water tank, that receives the conditioned fresh water streamvia the intermediate conduit(s). The storage tankmay store a volume of the conditioned fresh water upstream from the outlet. The storage tankmay be integrated with the mixing valveor may be a separate component. The storage tankmay be positioned between the heat pumpand the mixing valve. The conditioned fresh water may be stored in the storage tankfor future use, e.g., for future supply to the mixing valveto produce the mixed water streamwith the second fresh water streamat a desired temperature. The storage tankmay include one storage tank or multiple storage tanks.

The conditioned fresh water stored in the storage tankmay be supplied to the mixing valveas a stored water streamvia one or more second intermediate conduits. The storage tankand/or the second intermediate conduit(s)may be equipped with one or more outlet control valves controlling the supply of the stored water streamto the mixing valve. For example, the outlet control valve(s) may be controllable to initiate, terminate, and/or adjust flow of the stored water streamfrom the storage tankto the mixing valve. The outlet control valve(s) may be controlled manually and/or via the controller(s). The outlet control valve(s) may be controlled to initiate, terminate, and/or adjust flow of the stored water streamvia the controller(s)based on, or in response to, a user input indicative of a desired temperature of the dispensed fresh water streamin the space. The user input may be received via the user interface. Additionally or alternatively, the controller(s)may be operable to control the outlet control valve(s) based on or according to a temperature setpoint of the dispensed fresh water streamand/or the mixed water stream, which may be set or dynamically adjusted according to a user input, according to stored user preferences, according to a pre-programmed routine, etc. The mixing valvemay be controlled as described above in conjunction with or in the alternative to the outlet control valve(s) of the storage tankfor controlling flow of the stored water stream.

The storage tankmay also be connected with a conditioned water supply, e.g., a hot water supply, that may replenish or supplement the volume of conditioned fresh water stored in the storage tank. A supplemental conditioned water streammay be supplied from the conditioned water supplyvia one or more supplemental conditioned water conduits. The storage tankand/or the supplemental conditioned water conduit(s)may be equipped with one or more inlet control valves controlling the supply of the supplemental conditioned water streamto the storage tank. For example, the inlet control valve(s) may be controllable to initiate, terminate, and/or adjust flow of the supplemental conditioned water streamto the storage tank. The inlet control valve(s) may be controlled manually and/or via the controller(s). The inlet control valve(s) may be controlled to initiate, terminate, and/or adjust flow of the supplemental conditioned water streamvia the controller(s)based on, or in response to, a user input or feedback indicative of a low level of stored conditioned fresh water in the storage tank. The feedback indicative of a level of the stored conditioned fresh water may be received via one or more level sensor(s) included in the storage tank.

depicts another example of a water distribution systemthat may include similar components to the systemof, the systemof, and/or the systemof. Like elements and components between the system,and/orand the systemmay be indicated using like reference numerals. For example, the water distribution systemmay include the heat pumpoperable to transfer heat between the first fresh water streamand the wastewater stream, thereby producing the conditioned fresh water streamand the drain stream. The water distribution systemmay also include the mixing valvethat may operate to further condition the fresh water before it is dispensed via the outletas the fresh water stream. Additionally, the water distribution systemmay include a thermal storage device, e.g., a thermal battery. The thermal storage devicemay be integrated with the mixing valveor may be a separate component. The thermal storage devicemay be positioned between the heat pumpand the outlet. The thermal storage devicemay receive the conditioned fresh water streamvia the intermediate conduit(s). Additionally or alternatively, the thermal storage devicemay be directly connected to or integrated with the heat pumpand may transfer heat directly with the heat pump. The thermal storage devicemay include one thermal storage device or multiple thermal storage devices.

The thermal storage devicemay absorb heat from the conditioned water stream. Additionally or alternatively, the thermal storage devicemay absorb heat directly from the heat pump. For example, the thermal storage devicemay contain a heat storage material that absorbs the heat from the conditioned water streamand/or the heat pump. The heat storage material may include a phase change material. Non-limiting examples of phase change material may include hydrated salts, fatty acids, and paraffin wax. The phase change material may transition into a first phase, e.g., a gaseous phase, when absorbing the heat energy from the conditioned water streamand/or the heat pump. The phase change material may subsequently transition into a second phase, e.g., a liquid or solid phase, when rejecting the absorbed heat energy. In this way, the thermal storage devicemay harvest heat energy from the conditioned water streamand/or the heat pumpand store the harvested heat energy for later use to assist in heating a fresh cold water stream. The harvested heat energy may be stored via the thermal storage deviceand remain usable, for at least a period of time, for later activations of the system. Thus, for example the systemmay avoid losing all of the heat energy that may be available following the conclusion of a shower or other water distribution operation.

The thermal storage devicemay reject the stored heat energy to produce a heated fresh water stream. The heated fresh water streammay be directed to the mixing valveand/or the outletvia one or more third intermediate conduits. The thermal storage devicemay produce the heated fresh water streamby rejecting the stored heat energy into a third fresh water stream. The third fresh water streammay be supplied from a third fresh water supplyvia one or more third fresh water conduits. The third fresh water supplymay be or include the fresh water supplyand/or the second fresh water supplyor may be or include a different water supply.

In the embodiments described above with reference to, components and elements may be illustrated and described as individual components and elements. It is understood that multiple of such components and elements may be integrated to cooperatively perform the functions of the individual components and elements unless expressly stated otherwise or the context clearly indicates otherwise. For example, all or part of the heat pumpmay be integrated or incorporated in the receptacle. Additionally or alternatively, the mixing valvemay be integrated with the storage tankand/or the thermal storage device. Additionally or alternatively, the storage tankand the thermal storage devicemay be integrated with each other.

Referring to, a methodof operating a water distribution system, e.g., the system,,, and/or, is depicted. The methodmay include dispensinga first water stream into a space, e.g., the space, via an outlet, e.g., the outlet. Use of the first water stream in the space may produce a second water stream, e.g., the wastewater stream. The methodmay also include collectingthe second water stream, e.g., using the receptacle. The second water stream may be collectedwithin and/or downstream from the space. The methodmay also include transferringheat between the second water stream and the first water stream via a heat pump, e.g., the heat pump. For example, the methodmay include absorbing heat from the second water stream and rejecting heat into the first water stream via the heat pump, thereby raising the temperature of the first water stream. Additionally or alternatively, the methodmay include absorbing heat from the first water stream, thereby lowering the temperature of the first water stream, and rejecting heat into the second water stream. The heat pump may be located upstream from the outlet to control a temperature of the first water stream being dispensed into the space. The first water stream may encompass or include the first fresh water stream, the conditioned water stream, the dispensed water stream, and, optionally, one or more intermediate water streams between the heat pump and the outlet as described herein.

In some examples, the methodmay include combining the first water stream with a third water stream via a mixing valve, e.g., the mixing valve. The mixing valve may be positioned between the heat pump and the outlet. A temperature of the third water stream entering the mixing valve may be lower than a temperature of the first water stream entering the mixing valve. The third water stream may be or may include the fresh water streamsupplied via the supply.

In some examples, the methodmay include storing a volume of the first water stream in a storage tank, e.g., the storage tank. The storage tank may be positioned between the heat pump and the outlet. In some examples, the methodmay include absorbing heat from the first water stream and/or the heat pump via a thermal storage device, e.g., the thermal storage device. The thermal storage device may be positioned between the heat pump and the outlet. The thermal storage device may reject heat into a third water stream, e.g., the fresh water stream. In some examples, the methodmay include controlling, e.g., via the controller(s), at least one operating parameter of the heat pump according to a desired temperature of the first water stream being dispensed into the space.