Abstract
A fireplace system includes a fireplace, a thermal energy storage system (TESS) implemented with the fireplace and including one or more heat storing materials in which thermal energy is stored, and a control system comprising one or more controllers operatively coupled with the fireplace and the TESS. The control system is operable to control operation of the fireplace and the TESS to release the stored thermal energy from the one or more heat storing materials into a surrounding environment based on one or more inputs.
Claims
1. A fireplace system comprising: a fireplace; a thermal energy storage system (TESS) implemented with the fireplace and including one or more heat storing materials in which thermal energy is stored; and a control system comprising one or more controllers operatively coupled with the fireplace and the TESS, wherein the control system is operable to control operation of the fireplace and the TESS to release the stored thermal energy from the one or more heat storing materials into a surrounding environment based on one or more inputs.
2. The system of claim 1, wherein one or more of the fireplace or the TESS are fluidly coupled with one or more vents for intake or outflow of air, and the TESS is configured to release the stored thermal energy through the one or more vents.
3. The system of claim 1, wherein the one or more inputs include user inputs, instructions from a programmable or smart thermostat operatively coupled with the fireplace, sensor data associated with the fireplace or the TESS, or data from an external input device.
4. The system of claim 3, wherein the external input device includes one or more of: an electric utility grid from which the fireplace and the TESS receive electrical power, or a weather monitoring system.
5. The system of claim 3, wherein the control system selects an operating mode from a plurality of operating modes based on the one or more inputs, and wherein the plurality of operating modes includes different heat outputs and durations.
6. The system of claim 1, wherein the one or more heat storing materials include one or more air cavities through which the air passes during the operation of the fireplace and the TESS.
7. The system of claim 6, further comprising one or more fans or one or more blowers configured to generate convection to facilitate intake or outflow of air or the passing of air through the one or more air cavities.
8. The system of claim 6, wherein the one or more heat storing materials include a plurality of heat storing materials arranged in an assembly having a repeating pattern, and the assembly defines the one or more air cavities.
9. The system of claim 6, wherein the one or more heat storing materials include a monolithic structure of heat storing material, and the one or more air cavities extend through the monolithic structure.
10. The system of claim 9, wherein the one or more air cavities extend parallel to each other through the monolithic structure.
11. The system of claim 6, wherein the one or more heat storing materials include a monolithic structure of heat storing material having a plurality of continuous pores that are interconnected to form a network of airflow pathways, and the one or more air cavities extend through the continuous pores of the monolithic structure.
12. The system of claim 9, wherein the one or more heat storing materials include a plurality of the monolithic structures in a stacked configuration to add or reduce a heating capacity of the TESS.
13. The system of claim 9, wherein the one or more heat storing materials include a plurality of the monolithic structures arranged in a repeating pattern or matrix.
14. The system of claim 6, wherein the one or more heat storing materials includes a first sensible or latent heat material portion having a first cavity and a second sensible or latent heat material portion having a second cavity, the second sensible or latent heat material portion is disposed within the first cavity, and the second cavity is one of the one or more air cavities.
15. The system of claim 14, wherein the first sensible or latent heat material portion and the second sensible or latent heat material portion are made of different materials.
16. The system of claim 6, wherein the TESS comprises one or more separators at least partially defining the one or more air cavities.
17. The system of claim 6, wherein the TESS comprises a pipe at least partially defining the one or more air cavities.
18. The system of claim 1, wherein the TESS comprises a housing storing therein the one or more heat storing materials.
19. The system of claim 18, wherein the housing comprises at least a first housing component and a second housing component configured to be disposed within the first housing component.
20. The system of claim 19, wherein the first housing component and the second housing component at least partially defines the one or more air cavities.
21. The system of claim 18, wherein the TESS comprises one or more heating elements disposed within the housing and configured to increase temperature of the one or more heat storing materials.
22. The system of claim 2, wherein the one or more vents of the fireplace are disposed on a front portion of the fireplace.
23. The system of claim 22, wherein the TESS is coupled with the fireplace at a rear portion of the fireplace.
24. The system of claim 22, wherein the fireplace comprises a display, and the one or more vents of the fireplace are disposed adjacent to the display.
25. The system of claim 22, wherein a side portion of the TESS includes an intake vent facilitating intake of air.
26. The system of claim 1, wherein the control system is operable to: select between a first mode in which a first heater associated with the TESS is activated and a second mode in which a second heater associated with the fireplace is activated; and manage power use to direct power to the first heater or the second heater.
27. The system of claim 26, wherein the control system is operable to: select one of at least three operation states comprising: a) a first operation state in which the first heater is powered; b) a second operation state in which the second heater is powered; and c) a third operation state in which both the first heater and the second heater are powered.
28. The system of claim 27, wherein the one of the at least three operation states is selected based on one or more of: an increased power source or an additional power source.
29. The system of claim 26, wherein the control system is operable to: manage the power use for the first heater based on predicted weather data.
30. The system of claim 26, wherein the control system is operable to: manage the power use by enabling or disabling heat delivery from the TESS based on an indication from a smart hub control device.
31. The system of claim 26, wherein the control system is operable to: manage the power use by enabling heat delivery from the TESS based on a detected loss of electricity from one or more power sources.
32. The system of claim 26, wherein the control system is operable to: manage the power use by activating the first heater and enabling charging of the TESS during an off-peak time; and manage the power use by activating the first heater and enabling charging of the TESS during a non-off-peak time in response to user approval.
33. The system of claim 26, wherein the control system is operable to: manage the power use during a first period of time by activating the first heater and enabling charging of the TESS; and manage the power use during a second period of time subsequent to the first period of time by activating the second heater and releasing the stored thermal energy from the one or more heat storing materials of the charged TESS into the surrounding environment, wherein a heat output from a combination of the second heater and the charged TESS is greater than a heat output from the second heater alone.
34. The system of claim 1, wherein the control system is operable to: perform a system fault check procedure in response to the system being powered on; perform a heat delivery evaluating procedure in response to the system fault check procedure confirming there is no system fault; perform a charge evaluating procedure in response to the heat delivery evaluating procedure confirming there is no heat delivery from the TESS; and perform charging of the TESS in response to the charge evaluating procedure confirming that the TESS is to be charged.
35. The system of claim 1, wherein the control system includes a first controller operable to control operation of the TESS and a second controller operable to control operation of the fireplace and one or more fans associated with the TESS to control outlet temperature.
36. A method of controlling a fireplace system, the method comprising: selecting between a first mode in which a first heater associated with a thermal energy storage system (TESS) is activated and a second mode in which a second heater associated with a fireplace is activated, the TESS comprising one or more heat storing materials in which thermal energy is stored and releasable into a surrounding environment; and managing power use to direct power to the first heater or the second heater.
37. The method of claim 36, further comprising: selecting one of at least three operation states comprising: a) a first operation state in which the first heater is powered; b) a second operation state in which the second heater is powered; and c) a third operation state in which both the first heater and the second heater are powered.
38. The method of claim 37, further comprising: managing the power use during a first period of time by activating the first heater and enabling charging of the TESS; and managing the power use during a second period of time subsequent to the first period of time by activating the second heater and releasing the stored thermal energy from the one or more heat storing materials of the charged TESS into the surrounding environment, wherein a heat output from a combination of the second heater and the charged TESS is greater than a heat output from the second heater alone.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0044] The accompanying drawings are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments, and together with the description serve to explain the principles of the disclosure.
[0045] FIG. 1A is a schematic diagram of a fireplace system according to embodiments disclosed herein. FIG. 1B is a flowchart of a process for operating the fireplace system of FIG. 1A according to embodiments disclosed herein.
[0046] FIG. 2 is a partially exploded view of a fireplace system according to embodiments disclosed herein.
[0047] FIGS. 3A through 3C are schematic drawings of a fireplace system according to embodiments disclosed herein.
[0048] FIGS. 4A through 4D are schematic drawings of a thermal storage medium according to embodiments disclosed herein.
[0049] FIG. 5 is a flowchart of a process for controlling the operation of a fireplace system according to embodiments disclosed herein.
[0050] FIGS. 6A through 6C are images showing various views of a fireplace system according to embodiments disclosed herein.
[0051] FIGS. 7A and 7B are images showing various views of a fireplace system according to embodiments disclosed herein.
[0052] FIGS. 8A and 8B are images showing various views of a housing for a thermal energy storage system (TESS) according to embodiments disclosed herein.
[0053] FIGS. 9A through 9D are block diagrams of various fireplace systems according to embodiments disclosed herein.
[0054] FIG. 10 is a block diagram of a fireplace system according to embodiments disclosed herein.
[0055] FIGS. 11A and 11B are block diagrams of various fireplace systems that are remotely operable according to embodiments disclosed herein.
[0056] FIGS. 12 through 23 are flowcharts of various processes for controlling the operation of a fireplace system according to embodiments disclosed herein.
DETAILED DESCRIPTION
[0057] The present disclosure is generally directed to a fireplace or fireplace system which includes a fireplace (e.g., an electric fireplace), a thermal energy storage system (TESS) that is operable independently from the fireplace, and a control system that controls the operation of the fireplace, the TESS, or both. The fireplace is fluidly coupled with one or more vents for intake or outflow of air. The TESS is implemented with the fireplace and includes one or more heat storing materials in which thermal energy is stored. The control system is operatively coupled with the fireplace and the TESS. The control system controls operation of the fireplace and the TESS to release the stored thermal energy from the one or more heat storing materials into a surrounding environment through the one or more vents of the fireplace based on one or more inputs.
[0058] In some examples, the one or more inputs include user inputs, instructions from a programmable or smart thermostat operatively coupled with the fireplace, or data from an electric utility grid from which the fireplace and the TESS receive electrical power. In some examples, the control system selects an operating mode from a plurality of operating modes based on the one or more inputs, and the plurality of operating modes include different heat outputs and durations. For reference, the control system may automatically select operating modes or may receive a user input or other input that results in selection of an operating mode by the controller.
[0059] In some examples, the one or more heat storing materials include one or more air cavities through which the air passes during the operation of the fireplace and the TESS. In some examples, the system also includes a fan to generate convection to facilitate the intake or outflow of air or the passing of air through the one or more air cavities.
[0060] In some examples, the one or more heat storing materials include a plurality of heat storing materials arranged in an assembly having a repeating pattern, and the assembly defines the one or more air cavities. In some examples, the one or more heat storing materials include a monolithic structure of heat storing material, and the one or more air cavities extend through the monolithic structure. In some examples, the one or more air cavities extend parallel to each other through the monolithic structure.
[0061] In some examples, the one or more heat storing materials include a monolithic structure of heat storing material having a plurality of continuous pores that are interconnected to form a network of airflow pathways, and the one or more air cavities extend through the continuous pores of the monolithic structure. In some examples, the one or more heat storing materials include a plurality of the monolithic structures in a stacked configuration to add or reduce a heating capacity of the TESS. In some examples, the one or more heat storing materials include a plurality of the monolithic structures arranged in a repeating pattern or matrix.
[0062] In some examples, the one or more heat storing materials includes a first sensible or latent heat material portion having a first cavity and a second sensible or latent heat material portion having a second cavity, the second sensible or latent heat material portion is disposed within the first cavity, and the second cavity is one of the one or more air cavities. In some examples, the first sensible or latent heat material portion and the second sensible or latent heat material portion are made of different materials.
[0063] In some examples, the one or more vents of the fireplace are disposed on a front portion of the fireplace. In some examples, the TESS is coupled with the fireplace at a rear portion of the fireplace. In some examples, the fireplace comprises a display, and the one or more vents of the fireplace are disposed adjacent to the display. In some examples, a side portion of the TESS includes an intake vent facilitating intake of air.
[0064] FIG. 1A shows a block diagram of a fireplace system 100 according to embodiments disclosed herein. The system 100 includes a fireplace 102, such as a gas fireplace or an electric fireplace, and a thermal energy storage system (TESS) 104 coupled therewith. The fireplace 102 and the TESS 104 are both electrically coupled with a power grid or one or more power sources 106 to receive electric power. The TESS 104 includes any suitable material or configuration that allows heat or thermal energy to be stored over time in a high density that remains within the TESS, remains insulated from external elements, and is not distributed to a room unless instructed to do so. The TESS 104 is fluidly or operatively coupled with the fireplace 102 to provide thermal energy such as heated air that is stored inside the TESS. In some examples, the TESS may be attached to or located adjacent to the fireplace. In some examples, the TESS is not directly attached to the fireplace but is instead installed adjacent or nearby such that the heat provided by the TESS is sent to the fireplace via a duct or pipe, or any other suitable type of fluid connection. In some examples, the system 100 may include one or more fans or blowers 110 as well as one or more heaters 112, each associated with the fireplace 102 or the TESS 104.
[0065] In some examples, the power source 106 may include one or more batteries or battery electric storage systems (BESS), such as rechargeable lithium-ion battery packs, providing voltage to operate one or more components of the fireplace 102 or of the TESS 104 that is coupled therewith. In some examples, the power source 106 may include renewable (or natural) energy sources, and the TESS 104 may take advantage of peak electricity generation when natural energy sources are abundant (e.g., sun, wind, water, and/or geothermal energy), and the heat may be stored for use later when such sources are scarce.
[0066] The fireplace 102 and the TESS 104 may both be operatively coupled with a control system 108, which may include one or more controllers 109 such as a computer and/or a smart device, which is capable of sending instruction signals to the fireplace 102 and the TESS 104 to control operation of the fireplace and the TESS (or components associated with the fireplace and the TESS, such as vents, fans, heaters, etc.) in response to certain inputs such as user input or detection of certain conditions. In some examples, the control system 108 includes a single controller 109 controlling operation of the fireplace 102 and the TESS 104. In some examples, the control system 108 includes two or more controllers, such as controllers 109A and 109B for separately controlling operation of the fireplace 102 and the TESS 104, respectively. In some examples, the controller 109A that controls the fireplace 102 (as well as operation of the fan/blower 110A and/or the heater 112A associated therewith) may also control operation of the fan/blower 110B and/or the heater 112B of the TESS 104 so as to control the outlet temperature, for example. Conditions that may affect the operation of the fireplace system 100 includes but are not limited to: detection of a power outage, detection of the fireplace being disconnected from a power source, or update/calculation of electric utility rates. In some examples, the TESS 104 may be incorporated as a part of a home's smart environmental controls (e.g., thermostat and/or sensors) to better balance comfort and cost of delivery heating/cooling to the home, also opening opportunities for the home to be connected to a smart grid (e.g., via the controller) to allow utility (power grid) to better balance electricity demand. In some examples, the control system 108 may be connected to the Internet or other types of communications network to send and receive data regarding the electric utility.
[0067] The TESS 104 represents a heat battery. In some examples, the heat stored in a TESS may also be released from the system in a manner to better simulate an authentic fire experience. Some fireplaces using smaller power sources are incapable of heating a large space or providing an intensity of heat reminiscent of either a biomass or gas fireplace. The fireplace 102 that incorporates a TESS 104 would allow the TESS to provide more heat than an electric fireplace with a common power supply, such as a 120V power supply, can provide on its own. The TESS 104 may be operated to dissipate heat at a rate similar to that of an electric fireplace using a larger electric power source (such as a 240V power supply) for a certain period of time. The TESS 104 is sized through the main electric power source that the TESS is coupled therewith, and the amount of storage material (or heat storing material) included with the TESS. In a typical electric fireplace, choosing the rating of the power supply circuit sets the maximum amount of heat that the fireplace can deliver to a space. For a TESS-incorporated fireplace system, choosing a higher power-rated source allows the users to charge the TESS at a faster rate. Including a larger mass of storage material (or heat storing material) increases the total amount of thermal energy stored therein. The users may also purchase a TESS capable of providing heat to a room larger than what a similarly-sized electric fireplace could provide. Heat output may be provided at a slower rate to maximize the usage of the stored heat, or provided quickly to maximize the comfort of the users in the space. Users may select the system with a standard power source for ease of installation, such as 120 VAC, or select the system with a higher-rated power source to maximize charging speed for the TESS, such as 240 VAC. Referring to FIG. 1B, a process 120 illustrates an example for how the TESS and the fireplace may be operated according to embodiments disclosed herein. In step 122, the control system 108 is capable of selecting between a first mode that activates the heater 112B to charge the TESS 104 and a second mode that activates the heater 112A associated with the fireplace 102, and the control system 108 selects the first mode. In step 124, the heater 112B is activated to charge the TESS 104 during a first period of time. In step 126 (e.g., after a sufficient time has passed to charge the TESS 104 to a predetermined threshold level such as a predetermined internal temperature), the control system 108 selects the second mode to activate the heater 112A associated with the fireplace 102. In doing so, the heater 112B may be deactivated, thereby halting the process of charging the TESS 104. In step 128, during a second period of time subsequent to (or after) the first period of time, the stored thermal energy from the charged TESS is released into the surrounding environment, and the heater 112A associated with the fireplace 102 is also activated. As such, in step 128, more thermal energy (heat output) can be provided to the surrounding environment from the combination of the heater 112A and the charged TESS 104 than would be possible from the heater 112A alone at the same amount of power input.
[0068] In some examples, the TESS 104 may be scaled to meet the heating requirements of the users. A larger TESS may provide more heat for a longer time during a power outage or to provide consistent heat to a large room. A smaller TESS may be more economical, providing heat for the electric fireplace experience but not offering an extended heat supply during power outages. The sizing of TESS 104 is typically delineated by energy requirements to generate heat and total amount of heat stored. For example, a small TESS could provide less than 1 kW/hr of heat generating power and store 2 kW of heat over time. For example, a larger TESS may provide 2-3 kW/hr of heat generating power and store more than 10-20 kW of heat. In some examples, it may be advantageous to provide the TESS 104 with thermal battery units that are stacked or stackable to add or reduce the heating capacity of the TESS, for example as shown in FIG. 4C.
[0069] In some examples, the heat for the fireplace is not a point source consisting of an electric heater such as a positive temperature coefficient (PTC) heater or a resistive heater and an integrated blower/fan, thus providing more options for designing the heat extraction from the TESS. In some examples, a single duct/vent or multiple ducts, vents, and/or outlets may be provided to direct the heat in different ways to exit the fireplace system, as shown in FIGS. 3A and 3B. The TESS may also be paired with or include independent fans to assist in the heat extraction, for example to better simulate the heat emitted from a gas or traditional wood-burning fire. Using the TESS material may also simulate a more realistic ember/fuel bed and recreate the heat radiating from a gas or wood fireplace, thus providing a heating experience that is different from those of typical electric fireplaces. In some examples, a heat pump may also be combined with the TESS to balance the heat demanded by the heat pump.
[0070] FIG. 2 is a disassembled view of a fireplace system 200 that includes the fireplace 102 and the TESS 104 of FIG. 1A according to some embodiments. The system of FIG. 2 outwardly resembles and functions like a fireplace such as an electric fireplace but includes the TESS 104 that is attached to a rear portion 202 in a housing 204 of the fireplace (that is, the portion of the fireplace 102 facing away from a display 206 or the users receiving heat output from the fireplace). An electric fireplace may have a display 206 showing an image or video of a fire (or any other suitable graphic) located on a front portion 208, which also includes an intake vent 210 and an outlet vent 212. The intake vent 210 takes in air from the surrounding environment, and the outlet vent 212 exerts heated air that is generated or stored inside the system 200.
[0071] The fireplace 102 includes a fireplace housing 204, and the TESS 104 includes a TESS housing 214 that is attachable to the fireplace housing 204. The fireplace housing 204 includes the display 206 and defines the locations of the intake vent 210 and the outlet vent 212. The TESS housing 214 includes insulating material (not depicted) for retaining heat, and a thermal storage medium 216 (or alternatively referred to as a heat storing material) with high heat capacity that allows thermal energy to be stored in high density, and the thermal storage medium 216 may be configured in any form such as in layers or in blocks, or be formed in a monolithic structure, for example as shown in FIG. 4A or 4B. In some examples, a plurality of heat storing materials or thermal storage media 216 may be arranged in a repeating motif or pattern to form an assembly of heat storing materials, where each storage material element may not necessarily have an air channel or air cavity 218 extending through the storage material element, but the assembly of the heat storing materials would include one or more of such air channels or air cavities. In some monolithic structures, heating elements 220 may be embedded with the thermal storage medium 216 or sandwiched between multiple monolithic blocks of thermal storage medium 216 such as ceramic bricks. The thermal storage medium 216 may include one or more air cavities 218 to facilitate airflow pathways between the intake vent 210 and the outflow vent 212. In some examples, the thermal storage medium 216 may include any one or more materials such as sand and/or ceramic material that was ground into particles (or powder). In some examples, suitable materials such as phase-change materials (PCMs), water, alloys, salt hydrates, and/or ionic liquids may be implemented in the thermal storage medium 216. In some examples, multiple heat storing materials of thermal storage medium 216 can be combined together to form a dual system, such as a system of ceramic/inorganic materials and PCMs. Furthermore, such systems may be designed in nested, interlocking, and/or machined/milled shapes to better facilitate heat exchange between the thermal storage medium 216 and air/fluids that are used to extract the heat to the room. The thermal storage medium 216 may also function to insulate the stored heat so as to minimize heat loss or dissipation during storage.
[0072] In some examples, the thermal storage medium 216 may include a ceramic material paired with electric resistance elements capable of holding a large amount of heat and maintained therein for a prolonged period of time, for example from 2 to 4 hours, from 4 to 6 hours, from 6 to 8 hours, from 8 to 10 hours, from 10 to 12 hours, from 12 hours to 1 day, from 1 to 2 days, from 2 to 3 days, from 3 to 4 days, from 4 to 5 days, or any other suitable length of time. The TESS housing 214 also includes at least one fan 222 and/or at least one blower (not shown) that is electrically operated, which may be used to draw air (air inflow 224) into the TESS housing 214 and into the thermal storage medium 216 from the external environment (such as an indoor space) via the intake vent 210, and/or to discharge heated air (air outflow 226) via the outflow vent 212 using the convection generated by the fan 222 or using natural convection. A fan may be designed to facilitate general air circulation with a certain space or to push air out of the system, and a blower may be designed to move air to a specific (predetermined) location or to create a focused stream of fluid flow at a higher pressure. In some examples, heated air may be either delivered directly into the room or mixed with the air from the room in a way that increases the temperature of the air from the room before releasing the heated air back into the room, which may be assisted by incorporating the fan 222 or blower.
[0073] In some examples, heat from the TESS 104 may be released so as to provide a consistent temperature to the room in which the fireplace system 100 is installed, or the heat may be released at a higher rate so as to simulate a more intense or authentic fire experience for the users. This may be achieved while maintaining the power source at a low voltage level, such as 120V or lower, without increasing the power requirements (e.g., requiring the power source to increase in voltage level, such as from 120V to 240V) in order to generate the additional heat. In some examples, when paired with a control system or controller(s) as shown in FIG. 1A, the TESS 104 may be charged and discharged to take advantage of more affordable electric utility rates that are offered in some locales (e.g., off-peak rates or tariffs).
[0074] FIGS. 3A through 3C each shows a fireplace system 200 with a fireplace 102 (such as a gas or electric fireplace) and a TESS 104 coupled therewith. In FIG. 3A, a front portion 208 of the fireplace includes an intake vent 210 for receiving air inflow 224, and a side portion 302 of the TESS 104 also includes an intake vent 300 for receiving air inflow 224 that is separate from the intake vent 210 in the fireplace 102. The outflow vent 212 located in the front portion 208 of the fireplace 102 provides the heated air in an air outflow 226 into the surrounding environment. In FIG. 3B, the front portion 208 of the fireplace 102 includes a vent that facilitates both the air intake 224 and the air outflow 226 using the intake/outflow vent 304, and the air inflow 224 is further facilitated via the intake vent 300 located in the side portion 302 of the TESS 104. In FIG. 3C, the front portion 208 of the fireplace 102 includes a display 206, and disposed on the sides of the display 206 (such as on the left and right sides or the top and bottom sides) are the intake vent 210 for air inflow 224 and the outflow vent 212 for air outflow 226. In some embodiments, the air flow 224 follows a path that is vertical, but other air flow paths, including lateral, or tortuous (e.g., S-shaped or U-shaped) may be implemented.
[0075] In some embodiments, the TESS 104 is a stand-alone unit that may be separately and independently operable from the fireplace. The TESS 104 contains sensible and/or latent heat storing materials (thermal storage medium 216) combined with at least one electric heating element (e.g., heating elements 700 shown in FIGS. 7A and 7B) that is embedded in or between the heat storing material to maximize heat collection. The TESS 104 is insulated to contain the heat within the unit and to store this heat for an extended length of time. The TESS 104 may be bolted, fastened, or otherwise attached onto the fireplace 102 (such as at the rear portion of the fireplace) and may vent heat or heated air through existing output or outflow vents, such as the intake vent 210 or 300 and the outflow vent 212, and/or the intake/outflow vent 304. In some examples, the TESS 104 may be assembled as part of an integrated system where the vents are engineered to maximize heat extraction and thermal performance.
[0076] FIGS. 4A through 4D show different configurations of the thermal storage medium 216 as disclosed herein.
[0077] In FIG. 4A, a heat storing material or a thermal storage medium 216 is configured in the form of a solid brick or slab (e.g., in a monolithic structure) with one or more individual, continuous air cavities 218 that extend through the thermal storage medium 216, facilitating airflow pathways between the air inflow 224 and the air outflow 226. The thermal storage medium 216 may be designed to optimize airflow through the material in order to manage heat extraction. The individual, continuous air cavities 218 may be disposed parallel to each other.
[0078] In FIG. 4B, the thermal storage medium 216 is configured in the form of a brick or slab with continuous pores or cavities which may be interconnected to form a network of airflow pathways between the air inflow 224 and the air outflow 226.
[0079] In FIG. 4C, the bricks of FIG. 4A or 4B are stacked or arranged in any suitable structure to create continuous air cavities. For example, if the bricks of FIG. 4A are used, the individual, continuous air cavities from the multiple bricks may form one or more longer individual, continuous air cavities through the structure. For example, if the bricks of FIG. 4B are used, the continuous pores or cavities may allow continuous airflow between any two of the multiple bricks that used in the structure. In some examples, the monolithic structures may be arranged in a repeating pattern or a matrix.
[0080] FIG. 4D shows the thermal storage medium 216 including three portions: the air cavity portion 218, a first sensible/latent heat material portion 400, and a second sensible/latent heat material portion 402. A sensible heat material is the material used in a sensible heat storage, which stores energy by increasing the temperature of a medium having a high heat capacity. For example, the sensible heat materials used may include one or more of: water, stone, pebbles, rocks, concrete and/or sand, refractory materials, or other similar materials. A latent heat material is the material used in a latent heat storage, which stores or releases thermal energy during the phase change of the material. For example, the latent heat materials used may include one or more of: paraffin compounds, fatty acids, salt hydrates, eutectics, and/or fats and oils, especially fully hydrogenated fats and oils. Furthermore, note that some embodiments the arrangement of the thermal storage medium 216 is concentric circles, but other shapes may be suitable as well including but not limited to square, rectangular, and hexagonal. Furthermore, the arrangement could be a matrix, or layers, of sensible and latent heat materials as opposed to a single concentric set of sensible and latent heat materials.
[0081] The first heat material portion 400 surrounds the air cavity such that the air cavity, which receives the air inflow, is defined by the first heat material portion. The second heat material portion 402 surrounds the first heat material portion such that the first heat material portion is disposed between the air cavity and the second heat material portion. In some examples, the second heat material portion 402 has a preformed cavity (second cavity) in which a core, or the first heat material portion 400 (which defines therein the air cavity 218), is disposed or contained, such that the preformed cavity of the second heat material portion 402 is concentric with the air cavity 218 (first cavity) defined by the first heat material portion 400. The first heat material portion 400 and the second heat material portion 402 may be formed using the same material or using different materials with different properties such as heat capacity. Because the air cavity 218 carries heated air, the first heat material portion 400 may have a greater heat capacity than the second heat material portion 402 to accommodate the increased heat of the air that passes through the first heat material portion 400.
[0082] FIG. 5 shows a flowchart of a process 500 of controlling the operation of the fireplace system so as to deliver variable heat output. The process includes inputs 510, modes/settings 520, and outputs 530. The modes/settings 520 include, for example, a normal day-to-day mode 524 with general warmth and ambience, a heat boost mode 522 for users' comfort, and a power outage mode 526 for resilience. The heating output is the largest for the heat boost mode, and the smallest for the power outage mode. The system uses the TESS to provide additional heat in the normal day-to-day mode and the heat boost mode, while saving or conserving heat during the power outage mode, during which the fireplace may not be operating due to the lack of electricity from the power grid, for example.
[0083] In some examples, the inputs 510 may include user inputs from user interface 512, e.g., a touchscreen of a mobile device or monitor/display coupled with the fireplace system, instructions from the programmable or smart thermostat 514 that is implemented in the fireplace system, and/or notification from the electric utility grid 516 such as the power grid or the power supply company. Based on the input(s) 510, the process 500 determines or selects the next modes/settings 520 for the system, where each mode/setting operates the system differently, as explained above.
[0084] Based on the determined or selected mode/setting 520, the process 500 causes the system to output heat in a certain way based on the mode/setting. For example, the outputs 530 may include high heat output 532 for a short duration of energy storage (that is, of the TESS), a low-to-medium heat output 534 with a long duration of energy storage, and a low heat output 536 with a long duration of energy storage. Therefore, the outputs 530 determine both the intensity of heat output as well as an intended duration time for which the energy storage is expected to operate and provide the additional heat for the system. With greater heat output demand, the duration decreases because the TESS is expected to release the stored heat at a greater rate than in other lower-intensity outputs.
[0085] FIGS. 6A through 6C illustrate a TESS 104 configured as a nested enclosure for generating, storing, and delivering heat to a room. The nested design allows the heat to be stored for an extended period of time and delivered, on-demand, to a space (such as in a room). On-demand delivery is enabled by a blower system (including, for example, a fan) to push input air through a heat exchanger system providing control over volume and temperature of the delivered heated air. A blower system can have one blower or more than one blower; for example, a second blower can move air at a different temperature from the first blower, to mix in warmer or cooler air and modulate the temperature of delivered heated air. The nested enclosure ensures that air in the space is not in direct contact with the heat storage material or thermal storage medium, and any residues, odors, or particulates from the heat storage material or thermal storage medium will not negatively affect air quality within the space. The nested enclosure system may include one enclosure or more than one enclosure such that a sub-section of the system can be used to deliver heat to the space while another sub-section is instead generating or storing heat.
[0086] FIG. 6A shows an example of the TESS 104 in which the thermal storage medium 216 includes sensible heat materials that are in a solid, monolithic form (e.g. molded brick). The molded bricks are disposed within a first TESS housing component 214A in a stacked configuration as shown.
[0087] FIG. 6B shows the other side of the first TESS housing component 214A, which includes a plurality of separators 600 that at least partially define a flow path 602 for the air cavity 218 along which airflow may be facilitated during operation.
[0088] FIGS. 6B and 6C show the second TESS housing component 214B in which the first TESS housing component 214A may be disposed or nested to form the TESS housing 214. An inner surface 604 of the second TESS housing component 214B at least partially defines the flow path 602 when the first TESS housing component 214A is disposed inside or nested within the second TESS housing component 214B, such that the separators 600 and the inner surface 604 define the air cavity 218 and thus the flow path 602. The second TESS housing component 214B also defines the location of the intake vent 300 and the outflow vent 212.
[0089] As shown, the TESS housing 214 can include one or more sub-sections, each having all the elements of the TESS housing 214 but smaller in size than the completed TESS housing 214. The exterior of the first TESS housing component 214A has components that are attached in a way to create a channel that air can travel across the surface in a set path (e.g., the separators 600 forming the flow path 602). Doing so creates a heat exchanger system. Heat from the sensible heat material (thermal storage medium 216) is transferred to the airflow. This construction is housed in the second TESS housing component 214B that is insulated from outside air in a way that, when the heating elements (e.g., the heating elements 700 of FIGS. 7A and 7B) are disabled, heat is retained for a relevant duration in the thermal storage medium 216. At least two openings (intake vent 300 and outflow vent 212) are included in the second TESS housing component 214B allowing for air to enter and exit the enclosed path (flow path 602) that is formed from the nested design. Air can enter either through natural convection or can be provided by a blower/fan assembly (e.g., using a fan 222) or both.
[0090] FIGS. 7A and 7B illustrate another example of the TESS 104 which includes sensible heat materials that are in a powder or granular form (e.g. sand, or an aggregate of granular sensible heat materials). One or more heating elements 700 are included inside the TESS housing 214 and within the sensible heating material or thermal storage medium 216 such that the heating elements 700 can heat the sensible heating material or thermal storage medium 216 to a desired temperature. One or more blowers or fans 222 can be used to move air in, around, or through the system. A damper 706 is provided on the exit opening or outflow vent 212 to ensure heat does not escape, and another damper (not shown) can also be provided at the entrance or intake vent 300 to ensure minimum heat loss from the system. In some examples, a continuous thermal storage medium may be used with either an embedded airpath (e.g. a duct) or with an airpath molded in the bricks (thermal storage medium 216). This would provide the benefit of creating an airpath in intimate contact with the thermal storage medium 216 to facilitate heat exchange and minimize airflow resistance.
[0091] In some examples, the heating elements 700 may be disposed between two parallel portions of a pipe 704 to efficiently heat the pipe 704 as well as the air cavity 218 formed therein. The pipe 704 may be in the form of a sinusoidal or undulating configuration to maximize the path length of the air cavity 218 within a given volume. The pipe 704 may be made of any suitable material that is capable of conducting and tolerating heat, such as steel. The fan 222 may be positioned at any suitable location to assist in drawing out and circulating warmed air from the system to the room.
[0092] FIGS. 8A and 8B illustrate another example in which the first TESS housing component 214A may at least partially form the air cavity 218. Instead of the separators, an outer surface of the first TESS housing component 214A is configured in the form of a dent or a depression that defines the shape of the air cavity 218. The second TESS housing component 214B is disposed surrounding and supporting the first TESS housing component 214A and also defining the intake vent 300 as shown. In some examples, there may be more than two TESS housing components that are shown (e.g., there may be three or more TESS housing components). In some examples, the TESS housing components may be coupled with the thermal storage medium 216 of FIG. 6A. In some examples, the first TESS housing component 214A may also be at least partially filled with the granular form of thermal storage medium 216, such as sand. As such, the TESS 104 may be formed using one or both of the solid, monolithic form and the powder or granular form of the thermal storage medium 216.
[0093] It is to be understood that the figures are provided for illustrative purposes only, and that there are three variables regarding how the airflow through the system may be changed or altered. The first variable is path orientation; the orientation of the flow path 602 can be altered by changing the positions, orientations, shapes, and/or number of the separators 600. The second variable is surface area of the path; the surface area of the flow path 602 can be increased or decreased by changing the positions, orientations, shapes, materials, and/or numbers of separators 600. The third variable is path length; the length of the flow path 602 can also be increased or decreased based on the configuration of the separators 600. The separators 600 may be configured in any other suitable form, including but not limited to smooth, rough, straight, and curved. Different materials may also be used for the separators 600 such that the separators 600 may use materials different from the material used in the walls of the TESS housing 214.
[0094] By providing a nested enclosure for a heat storage system, heat storage in the heat storing material can be retained for longer periods of time and delivered at a desired time (time shifted) when the heat is called for from a control system. By designing the airflow path as shown, the heated air can be delivered at a more flexible volume, rate, and/or temperature than is possible with existing common, residential electric heat storage technology.
[0095] The use of more than one blower in the blower system allows for air mixing from two states that can be combined to moderate air output temperature. Air could be blown from, for example, the highest-heat internal heat storage system volume, from the surrounding room, and/or from an intermediate cavity within the heat storage system, among others. Additionally, the air mixing from more than one blower could be combined with metering from each contributing blower, such that the air temperature output from the system could be tuned to a target temperature or temperature range. Through this use of combined blowers and air of different temperatures, air output temperature to a room or space could be moderated more or less according to consumer preference. The design also provides for improved air quality in the space where the heated air is delivered as the room air does not come in direct contact with the sensible heat storing material. Time shifting of the heating and delivering of the heated air can provide for customized delivery of heat that is controlled by manual user operation or through a programmable controller or through smart home technology.
[0096] The use of one enclosure allows for generating, storing, and delivering heat to a room. The use of more than one enclosure or sub-sections separated within the enclosure allows for more than one action at the same time from one system. For example, one enclosure sub-section may deliver heat to a room while another enclosure sub-section may instead be generating or storing heat. Generating heat in one sub-section has the advantage to take less time to heat than generating heat in the full enclosure, thus shortening cycle time from a first state with no stored heat to a second state with full heat storage, or reducing the energy use of the system if the heat stored in a sub-section is sufficient to heat a room. Additionally, the use of more than one enclosure or sub-section separated within the enclosure with separate airflow paths could be reversibly and mechanically connected to add length to the airflow path and extend the time of heat delivery to a room or modulate temperature of heat delivered to a room.
[0097] FIGS. 9A-9D and 10 illustrate different examples of the fireplace system 100 at a high-level summary. It is to be understood that any suitable components such as switches (such as on-off and/or toggle switches), relays, circuit breakers, and connection pins may be implemented as well as other electronic parts such as resistors and capacitors, as part of the circuitry that comprises the systems disclosed herein. The numbers disclosed herein are also arbitrary, such that any higher or lower amount, as suitable, may be employed.
[0098] In FIG. 9A, a single power source (e.g., shown as a 120-voltage source, 120 V.sub.AC,L1 in the figure) is configured to provide power to the fireplace 102 and the TESS 104, where the circuit breaker controls whether the power source is able to distribute any power to the fireplace 102 and the TESS 104, and the pins (such as pin 1, pin 2, and pin 3 as labeled) are configured to provide electrical connection between the fireplace 102 and the TESS 104, which is controlled by switches (e.g., the switches labeled as TESS Disable and TESS Disconnect) in at least one of the fireplace 102 and the TESS 104. The switches may be controlled using the control system 108 to operate the fireplace 102 and the TESS 104 in any suitable way as disclosed herein. Each of the fireplace 102 and the TESS 104 may be controlled separately or independently.
[0099] The fireplace 102 includes a fireplace controller (FP Controls) and one or more heaters (Heater) associated with the fireplace 102. When the TESS Disable switch is operated in the open position, the TESS 104 is disconnected from the power source, and the fireplace 102 is allowed to use the electric power to activate the associated heater in order to generate heat, thus disabling the TESS 104 entirely. Alternatively, when the TESS Disable switch is in the closed position, the TESS Disconnect switch may be in an open position (in which the TESS 104 would still not receive any electric power) or a closed position (in which the TESS 104 would be able to receive electric power). The difference between disabling and disconnecting is that the disconnecting of the TESS 104 is temporary or for a short periods of time when the TESS 104 itself is still active and capable of providing heat, whereas disabling the TESS 104 causes the TESS 104 to be shut down and/or no longer active, such as when TESS 104 is discharged, thus no longer capable of providing heat even when the TESS 104 is activated.
[0100] In some examples, the power source may provide electric power to both the fireplace 102 and the TESS 104 simultaneously, such as when the TESS Disable and TESS Disconnect switches are both closed, and the heater associated with the fireplace 102 is activated by the controller. In such situations, the power source may simultaneously power the fireplace 102 and charge the TESS 104, and the power distribution between the fireplace and the TESS may be controlled using the controller (which may be any suitable ratio, e.g., 20% to the fireplace and 80% to the TESS, or 50% to both, or 80% to the fireplace and 20% to the TESS, etc.). In some examples, the TESS 104 includes a TESS distribution module 900 which operates to distribute the amount of power received to different purposes, such as to a TESS charging module 902 and a TESS heat supply module 904. The TESS charging module 902 operates to charge the TESS 104 to increase the internal temperature of the TESS 104 to a predetermined temperature. The TESS heat supply module 904 operates to deliver heat from the TESS 104 to increase the temperature of the external environment by releasing the stored heat within the TESS 104. In some examples, the TESS charging module 902 and the TESS heat supply module 904 may operate different heaters associated with the TESS 104. In some examples, the TESS heat supply module 904 may operate one or more dampers associated with the TESS 104 to release the heat stored therein or to release the heat provided by the heater associated with the TESS 104.
[0101] In FIG. 9B, the fireplace 102 is a primary device and the TESS 104 is a secondary device. For example, a primary device may be capable of controlling operation of a secondary device, but the secondary device is not capable of controlling operation of the primary device. The fireplace 102 includes a heat delivery request switch and a charge request switch which, when operated, controls how the TESS 104 operates. The heat delivery request switch and the charge request switch may be toggled such that when one switch is closed, the other switch is opened, when the TESS enabled switch and the TESS connected switch are both closed. Specifically, when the heat delivery request switch is closed, a TESS heat delivery request module 906 causes the TESS 104 to release its stored heat or to use the heater(s) associated therewith to provide heat for the external environment instead of charging the TESS. When the charge request switch is closed, a TESS charge request module 908 causes the TESS 104 to operate the heater(s) associated with the TESS to start charging the heat storing material of the TESS. In some examples, a fireplace thermal switch (FP TS) may be disposed in a series connection with the charge request switch to control the charging of the TESS 104 based on the temperature sensed by the thermal switch. Alternatively, when the TESS enabled switch or the TESS connected switch is opened, the TESS 104 is not allowed to provide heat or charge the heat storing material thereof. Therefore, the primary device (fireplace 102) controls permission for the TESS 104 using discrete outputs, which may include one or more of analog or wireless serial communications.
[0102] In FIG. 9C, the fireplace 102 is a primary device to a plurality of TESS units 104 which are all secondary devices whose permission is controlled by the primary device (fireplace 102). Although only two TESS units 104 are shown, it is to be understood that any suitable number of TESS units 104 (e.g., a total number of N secondary devices, such as TESS 104A, TESS 104B, . . . and TESS 104N) may be connected in a series connection. The plurality of TESS heat delivery request modules 906 and the plurality of TESS charge request modules 908 (where each module controls only the TESS unit that the module is associated with) may be connected in a series connection with respect to the primary device (fireplace 102). For example, when the TESS 104 is enabled on the fireplace 102 (and the TESS Connected switch is closed), the fireplace 102 provides permissions to a single TESS unit (e.g., only the TESS unit 104A). When the fireplace 102 closes the Charge Request switch, the TESS unit will activate its internal heater (or the heater associated therewith) to store heat in the thermal storage material. When the fireplace 102 sends a signal to close the Heat Delivery Request switch to request heat delivery, the TESS unit will deliver its internally stored heat as warm air to the surrounding environment or room. If the fireplace 102 has a thermal event, a hardware interlock in the fireplace, such as when the thermal switch is open, will stop the Charge Request and/or Heat Delivery Request instructions from being provided to the TESS unit by forcing the associated switch(es) to be open.
[0103] In FIG. 9D, the fireplace 102 is a secondary device to the TESS 104 which is a primary device. For example, the TESS 104 may control permissions for the operation of the one or more fireplace(s) 102 using a controls protocol such as discrete outputs in the form of one or more analog or wireless serial communications.
[0104] In FIG. 10, two separate and independent power sources (120 V.sub.AC,L1 and 120 V.sub.AC,L2) are provided, where the first power source L1 is operable to provide electric power to the TESS 104, whereas the second power source L2 is operable to provide electric power to the fireplace 102. The power sources L1 and L2 may be separately and independently controlled by the control system 108. It is to be understood that, although only two power sources are shown, any number of additional power sources may be implemented in combination to one or more of the aforementioned power sources L1 and L2 to provide more flexible power input for the fireplace 102 and/or the TESS 104. Furthermore, although the power sources L1 and L2 are shown having the same voltage level, it is to be understood that different voltage levels may be applied to the power sources L1 and L2, such that one of the power sources has a lower or higher voltage level than the other power source(s). In some examples, the power source with the lower voltage level may be applicable for the TESS, such as when charging the TESS requires less power or the fireplace requires more power to operate. Alternatively, in some examples, the power source with the lower voltage level may be applicable for the fireplace.
[0105] Using any one or more of the examples shown in FIGS. 9A-9D and 10, the control system 108 may be operable to select between a first mode in which a first heater associated with the TESS 104 is activated and a second mode in which a second heater associated with the fireplace 102 is activated and manage power use to provide or direct power to the first heater or the second heater. In some examples, the control system 108 may further be operable to select one of at least three operation states: a first operation state in which the first heater is powered (e.g., at an increased voltage level using all of the power sources); a second operation state in which the second heater is powered (e.g., at the increased voltage level using all of the power sources); and a third operation state in which the first heater and the second heater are both powered (e.g., for simultaneously operating the first heater using one of the power sources and the second heater using another one of the power sources, or for simultaneously directing power to both heaters using a common power source). In some examples, the one of the at least three operation states is selected based on one or more of: an increased power source or an additional power source, such that an increase in the power source or having the additional power source determines which operating state is selected and which heater is powered. In some examples, the modules as disclosed herein may be implemented as controllers or microcontrollers, including but not limited to a processing device with a memory device associated therewith. The memory device may be any suitable non-transitory machine-readable storage medium and may include one or more of: a solid-state memory, a magnetic disk, an optical disk, a portable computer diskette, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (e.g., EPROM, EEPROM, or Flash memory), or any other tangible medium capable of storing information, for example. In some examples, the processing device and the memory device may be integrated or incorporated into a single integrated circuit (IC) or a plurality of ICs. The memory device(s) may store thereon instructions (such as programming codes) to be executed by the processing device to perform one or more processes as disclosed herein.
[0106] In FIGS. 11A and 11B, the fireplace 102 and the (one or multiple) TESS unit(s) 104 are shown to be controllable wirelessly via a wireless signal 1104 using a phone 1100 and/or a remote 1102. In some examples, one or more fireplaces and one or more TESS units are each operated independently by one control system, for example a user interface on a controller such as a phone 1100 or remote 1102. In such instances, one or more of the fireplace(s) do not require permissions from a TESS unit to operate, and similarly, one or more of the TESS unit(s) do not require permissions from the fireplace(s) to operate. The independent operation of fireplaces and TESS units by one controls system may be enabled by wireless connectivity (e.g., 1104) or hardwired connectivity (not shown).
[0107] FIG. 12 is a process 1200 which may be implemented using, for example, a control system 108 associated with the fireplace 102 and the TESS 104. In step 1202, the control system determines that the power for the system is turned on. In step 1204, the control system enters a system fault check subroutine in which any system fault is checked prior to activating the TESS or fireplace of the system. If the result of the system fault check subroutine is true indicating that there is a fault in the system that is detected, the process proceeds to step 1206 in which the control system enters a cool down subroutine to cool down the system before returning to step 1204 to check for system faults again.
[0108] If step 1204 returns false indicating there is no system fault, the process proceeds to step 1208 in which charge level of the TESS is acquired, and user indicators are updated. The charge level may be defined as the amount of heat stored in the TESS, for example as indicated by whether the internal temperature of TESS has reached a threshold temperature which may be set by the user or by the manufacturer of the system. In step 1210, the control system enters an evaluate heat delivery request subroutine in which the control system analyzes the charge level as well as user indicators regarding whether charge mode was instructed. If step 1210 returns true, the process proceeds to step 1212 in which the control system disables the heaters, opens the damper(s), and enters a Heat Delivery subroutine, for example a PID or Proportional-Integral-Derivative control loop feedback mechanism. If step 1210 returns false, the process proceeds to step 1214 in which the control system enters an evaluate charge request subroutine. If step 1214 returns true, the process proceeds to step 1216 in which the control system enables the heaters, closes the damper(s), and disables the fans. If step 1214 returns false, the process proceeds to step 1218 in which the control system closes the damper(s) and disables the heaters and fans. After each of steps 1216 and 1218, the process returns to step 1204 to again check for any system faults. The subroutines will be explained in detail herein.
[0109] FIG. 13 shows a flowchart for the process 1204 associated with step 1204 in FIG. 12. Specifically, in step 1300, the control system receives instruction to enter the system fault check subroutine, and in step 1302, the control system checks for any critical fault that may have been detected. Examples of the critical fault may include, but are not limited to: thermocouples associated with the TESS detecting an overtemperature condition (indicating a possible overheating condition in the TESS); sensors associated with the fireplace detecting a possible thermal event (indicating that the fireplace may be reaching a temperature that is too high for the safety of the users); fireplace or TESS outputting one or more critical errors such as sensor failures or short circuits within the components; indications of a fan failure; and/or indications of failure of heating element(s) associated with the fireplace and/or TESS. If there is any critical fault detected, the process 1204 returns true and enter the cool down subroutine of step 1206. Otherwise, if there is no critical fault detected, the process 1204 returns false indicating that the system is safe, thus exiting the subroutine, in step 1304. In some examples, the process may also include additional or alternative steps such as receiving data such as measurement data or status indicators from one or more of: thermocouple(s), sensor(s), fireplace or TESS output(s), and/or fan(s) or heating element(s) associated with the system, in order for the control system associated therewith to gain information or data to initiate other processes as disclosed herein.
[0110] FIG. 14 shows another flowchart for the process 1204 according to another example. According to this example, in step 1400, the control system detects any auxiliary system failure. Auxiliary systems may include the fan system, the sensor system, the thermostat system, and/or any other device or component system that facilitates monitoring and controlling of the fireplace and the TESS. For example, a smart home controller may be one of such device systems, as well as the Internet connection that is required by such controller to operate the fireplace and the TESS accordingly. If no system failure is detected, the process proceeds to step 1402 in which any sensor fault is assessed or detected. The sensor may include any sensor that takes measurements associated with the operation of the fireplace and the TESS, including measurements such as electrical current, temperature, etc. If no sensor fault is detected, the process proceeds to step 1404 in which any overtemperature of the components is assessed or detected. For example, if any component (such as the components associated with the fireplace or the TESS) has a measured temperature that is above the threshold temperature deemed safe for operation, such condition would be detected as an overtemperature event. If no such overtemperature event is detected, the system fault check returns with a false indicating that the system is safe, thus exiting the subroutine, in step 1304. If any of steps 1400, 1402, and 1404 indicated yes (i.e., there is an auxiliary system failure, sensor, fault, or overtemperature event), the system fault check returns with a true and the system enters the cool down subroutine in step 1206.
[0111] FIG. 15 shows a flowchart for the process 1210 associated with step 1210 in FIG. 12. In step 1500, the control system receives instruction to enter heat delivery request subroutine. In step 1502, the control system determines if the heat delivery mode for the TESS was instructed, such as by the user. If so, the process proceeds to step 1504 in which the control system determines if the charge level of the TESS is above a predetermined threshold. This threshold may be a temperature threshold set by the user or by the manufacturer. If the charge level is above threshold, in step 1506, the control system determines if the hysteresis indicates to deliver heat from the TESS. A hysteresis is a buffer in the temperature (charge level) of the TESS that prevents the system from constantly turning on and turning off the activation of TESS within a short amount of time, such as in the range of a few degrees of temperature above and below a target temperature. Therefore, according to the hysteresis, if the charge level of the TESS is above the minimum charge threshold but is not above the buffer provided by the hysteresis, then the process proceeds to step 1510 to return false and exit the subroutine. Otherwise, if the charge level is above the minimum charge threshold and also above the buffer provided by the hysteresis, the process proceeds to step 1508 to return true and exit the subroutine. Additionally, if the result of step 1502 or 1504 is a no, the process also proceeds to step 1510.
[0112] FIG. 16 shows a flowchart for the process 1214 associated with step 1214 in FIG. 12. In step 1600, the control system receives instruction to enter evaluate charge request subroutine. In step 1602, the control system determines if the charging mode for the TESS was instructed, such as by the user. If TESS charging is instructed, the process proceeds to step 1604 in which the control system determines if the charging of the TESS has been permitted, for example by the user via instructions entered using a user interface, or by analyzing whether or not the fireplace is currently using the heat (exerting heat generated using the power source input), and if the fireplace is not using the heat, then TESS charging is permitted. If TESS charging is permitted, the process proceeds to step 1606 in which the control system detects the charge level of the TESS, such as by measuring the temperature of the TESS using a sensor associated therewith. Then, in step 1608, the control system determines if the hysteresis indicates to charge the TESS, based on the detected charge level. For example, the hysteresis may indicate a hysteresis loop where, upon the charge level reaching an upper threshold, the charge level is allowed to drop to a lower threshold and then charged again to reach the upper threshold. As an illustrative example, if the charge level is at 50%, the hysteresis may permit the TESS to be charged to initially reach an upper threshold of 100%. Upon reaching this upper threshold, the charging is stopped such that the TESS is allowed to discharge over time until its charge level reaches a lower threshold of 80%. When the 80% threshold is reached, the TESS is again allowed to charge to reach the upper threshold of 100%, and the cycle or loop may continue so as to (1) prevent the TESS from a possible overtemperature event due to too much charging, and (2) allow the power source to be used by other components such as the fireplace heater when the TESS does not need to use the power source for charging. If the hysteresis says to charge the TESS (such as according to the hysteresis loop), then in step 1610, the process returns true and the control system exits the subroutine. Otherwise, if the result of any of steps 1602, 1604, and 1608 was no, the process returns false and the control system exits the subroutine.
[0113] FIG. 17A shows a flowchart for the process 1212 associated with step 1212 in FIG. 12. In step 1700, the control system receives instruction to enter Heat Delivery subroutine. In step 1701, the control system calculates fan speed(s) needed for the system. For example, calculations may be completed using a PID (as shown in FIG. 17B) or fan speed lookup tables (as shown in FIG. 17C). In step 1708, the control system operates the fan(s) based on the determined fan speed(s) such as by applying the determined speed(s) to the fan channel(s).
[0114] FIG. 17B shows a flowchart for the process 1212 associated with step 1212 in FIG. 12, in further example of step 1701 in FIG. 17A. In step 1700, the control system receives instruction to enter Heat Delivery subroutine. In step 1702, the control system receives instruction to enter Heat Delivery PID subroutine, which instructs the control system to use PID as part of the process for calculating fan speed(s). In some examples, the instruction to enter the Heat Delivery subroutine may include the instruction to enter the Heat Delivery PID subroutine (e.g., provided together as a single instruction). In some examples, the instructions may be provided separately. In step 1703, the control system measures the outlet temperature associated with the system. For example, the outlet temperature may be the temperature measured at the outflow vent 212 of the TESS 104 or the fireplace 102. In step 1704, the control system computes outlet temperature vs target temperature, or the difference (or error) between the outlet temperature and the target temperature. For example, the measured (or actual) outlet temperature and the target (or ideal) temperature for the appropriate component, such as the TESS or fireplace, may be compared for the computation. In step 1706, based on the computation, the control system determines an appropriate Heat Delivery PID output to compensate for the difference or error between the actual and ideal outlet temperatures. For example, the Heat Delivery PID output may be a speed of the fan that is operated to generate convection within the TESS which facilitates on-demand delivery by using a blower system (fan) to push input air through a heat exchanger system providing control over volume and temperature of the delivered heated air. In some examples, step 1706 further includes clamping the Heat Delivery PID output to be within a reasonable or appropriate range of fan output, for example adjusting the Heat Delivery PID output such that the speed of the fan is within a predetermined operable region as determined by the manufacturer, for safety or efficiency of the fan, for example. In step 1708, the determined speed is applied to the fan channels such that the fan(s) would be operated at the determined speed from step 1706.
[0115] FIG. 17C is a flowchart for the process 1212 associated with step 1212 in FIG. 12 for operating the fan(s) according to examples disclosed herein. Subsequent to step 1700, in step 1710, the control system receives instructions to enter a heat delivery fan speed lookup subroutine in further example of step 1701 in FIG. 17A which instructs the control system to use one or more lookup tables as part of the process for calculating fan speed(s). In some examples, the instruction to enter the Heat Delivery subroutine may include the instruction to enter the heat delivery fan speed lookup subroutine (e.g., provided together as a single instruction). In some examples, the instructions may be provided separately. In step 1712, the control system obtains the charge level of the TESS. In some examples, the charge level may be obtained by one or more sensors associated with the TESS, such as a thermometer. In some examples, the charge level may be estimated or predicted based on analyzing the previously measured charge levels or charge level data as received from one or more devices such as a user input device. In step 1714, the fan speed(s) are determined based on the charge level using one or more lookup tables. For example, upon obtaining the charge level, the control system may determine the appropriate speed of one or more of the fans by referring to the one or more lookup tables stored in a memory device associated with the control system or accessible by the controller. In some examples, the lookup table may indicate a single fan speed to implement at a current time, or a plurality of fan speeds to implement over a period of time. In some examples, the lookup table may indicate different speeds for different fans within the system, such as based on the locations of the fans or the sizes of the fans to be operated. In step 1708, the control system operates the fan(s) based on the determined fan speed(s). In some examples, the Heat Delivery PID subroutine may be used to determine fan speeds as shown in FIG. 17B. In some examples, the heat delivery fan speed lookup subroutine may be performed in lieu of the Heat Delivery PID subroutine of step 1212 as shown in FIG. 17C which also determines the fan speed. In some examples, the fan speed lookup subroutine of FIG. 17C may be performed in addition to the Heat Delivery PID subroutine of FIG. 17B such that the lookup table may be used to supplement the Heat Delivery PID subroutine by operating as a second opinion for the fan speed determination process. In some examples, the heat delivery fan speed lookup subroutine and the Heat Delivery PID subroutine may be combined such that the final speed(s) of the fan(s) may be determined by combining the fan speeds as separately determined in each subroutine. One example of such combination may be to take the average (or midpoint) of the fan speeds as determined by the individual subroutines, and the control system operates the fans according to this average or midpoint fan speed. In some examples, the average may be weighted such that the determined speed of one subroutine has greater weight than the other determined speed of the other subroutine.
[0116] FIG. 18 shows a flowchart for a process 1800 which may be included at any part of the process 1200 in FIG. 12 in order to inject a user command or user input into the process. In step 1802, the control system detects an actuation of a control button, such as by a user input. In step 1804, the control system toggles between a charge state and a heat delivery state of the TESS based on whether the charge button or heat delivery button was actuated in step 1802. In step 1806, the TESS is operated according to the charge state or the heat delivery state as toggled. In some examples, the control button can override one or more steps in the process 1200 because the control system prioritizes user input over other features, to a degree.
[0117] FIGS. 19A and 19B are flowcharts of processes 1900 for controlling charge mode based on predicted weather data.
[0118] In FIG. 19A, in step 1902, the control system receives predicted weather data from a weather monitoring system. The weather monitoring system may be any suitable system such as a software application on a computing device or a cloud computing network which transmits weather forecast to individual devices operably coupled with the network. In step 1904, based on the predicted weather data, the control system determines one or more possible adverse conditions in an upcoming period of time. The upcoming period of time may be hours, days, or weeks in advance. In step 1906, the control system manages the power use for the heater associated with the TESS based on the predicted weather data, such as by enabling charge mode of the TESS at full capacity in response to determining that there are possible adverse conditions. For example, when there is a predicted thunderstorm, there may be a risk of power outage in the area, so the TESS is charged at full capacity in order to maximize the amount of charge that the TESS will be able to hold when the power outage takes place, such that the TESS will be capable of providing heat even in the absence of electricity in the area. In doing so, any electricity saving mode, such as delaying the charging of TESS until when electricity is cheaper at night, for example, is overridden to prioritize maximum speed charging of the TESS.
[0119] In FIG. 19B, after step 1902, the control system may determine that there are fair weather conditions in the predicted weather data in step 1908, in which case, in step 1910, the control system enables charge mode at a reduced electricity usage or delay the charging to an appropriate time in the future such that the TESS is not necessarily charged at the present time, because there is no predicted adverse condition in the near future.
[0120] FIG. 20 is a flowchart for a process 2000 for implementing a smart hub control. In step 2002, the control system activates smart hub control. A smart hub may be a smart home device such as a thermostat or any other smart device associated with the control and management of a home system, including but not limited to a smartphone, a smart tablet, and/or a smart speaker. In some examples, the smart hub may include one or more mobile devices for remote access to the home system, as well as a smart device app (software app) to control the home system. In step 2004, the control system allows the smart hub control to toggle the heat to be on or off. For example, the smart hub may automatically control to change the heat setting, based on determining that it is appropriate to do so. Based on the toggling, or based on an indication from a smart hub control device, in step 2006, the control system manages the power use by enabling or disabling the heat delivery mode of the TESS, such that when the heat delivery mode is enabled, the TESS is allowed to deliver the heat stored therein to the surrounding environment, for example by opening a damper.
[0121] FIG. 21 is a flowchart for a process 2100 for controlling heat delivery during a power outage. In step 2102, the control system determines that there is loss in home electricity (or loss in power grid connection providing the electricity to the fireplace and TESS system). In step 2104, the control system manages the power use by enabling backup battery power. In step 2106, the control system determines whether or not the electricity loss is still maintained. If the electricity loss is no longer present (i.e., there is power in the power grid), the process returns to step 2102. Otherwise, if the electricity loss is still maintained, in step 2108, the control system waits until receiving a user input, such as a local or remote user input, instructing to deliver heat from the TESS. In response to the user input in step 2108, the control system manages the power use by delivering heat from the TESS in step 2110.
[0122] FIG. 22 is a flowchart for a process 2200 for controlling off-peak charging of the TESS. In step 2202, the control system detects off-peak charge mode being enabled by the user. Generally, electricity is more expensive during the day when there is higher demand, and lower at night when there is lower demand. The high-demand and low-demand times may vary from season to season. Therefore, based on when the demand is low (i.e., off-peak demand), the control system operates the charging of TESS so as to only charge during off-peak hours. In step 2204, the control system receives a charge request, for example from a user via user input. In step 2206, the control system determines whether or not the current time is considered off-peak time. If so, in step 2210, the control system manages the power use by enabling the charge state of the TESS. Otherwise, the process proceeds to step 2208 in which the control system checks if user approval is received for such charging at a non-off-peak time (i.e., peak demand time). The control system may ask the user via a notification requesting the user to confirm that charging of the TESS at a peak-demand time is permitted by the user. Upon receiving the confirmation or permission to do so, the control system proceeds to enable the charge state in step 2210. However, if no such approval or permission is received or granted, the process proceeds to step 2212 in which the charge state of the TESS is disabled by the controller.
[0123] FIG. 23 is a flowchart for the process 1206 associated with step 1206 in FIG. 12. Specifically, in step 2300, the control system receives instruction to enter the cool down subroutine, and in step 2302, the control system manages the power use by disabling the heater(s). The heater(s) may refer to any one or more of the heaters associated with charging the TESS. In step 2304, the control system operates the fan(s) associated with the TESS by turning off or deactivating the fan(s), thus stopping the airflow or convection through the TESS. In step 2306, the damper(s) are opened such that the heat stored within the TESS may be released, dissipated, or delivered to the external environment. The damper(s) may include one or more dampers. In some examples, for safety purposes, the fans are deactivated during the heat release or dissipation process such that the amount of heat that is released or dissipated into the external environment is passive. However, in some examples, if rapid cooldown of the TESS is necessary, one or more fans may be implemented to draw air out from within the TESS to quicken the heat release or dissipation process, as suitable. Afterwards, the control system may return to step 1204 of performing the system fault check subroutine to check for any system faults again, as disclosed herein.
[0124] While example combinations of features have been described above in association with the various figures, those features may be combined, substituted, and/or modified with one another across the various examples.
[0125] Implementing the TESS with the fireplace beneficially allows for the system to build up heat that can be accessed at a future time or at an intensity level that is not possible with only the fireplace. Because thermal energy is stored for use later, heat can be provided when electrical power is not available to the home, such as when an adverse event happens (e.g. brown-out, wild-fire, or storms), or is otherwise in use, such as to power other components. Using a TESS also provides advantages over using a BESS to provide backup electricity to the fireplace during an outage. A typical electric fireplace heater has power requirements (e.g., 1.5 kWh) that would require a physically large BESS capacity to operate the fireplace heater for an extended period (e.g., longer than 1 or 2 hours) at maximum output. Storing the necessary energy for the electric fireplace to provide heat during a power outage as heat using the TESS allows the fireplace system to store more energy and access the stored energy with no (or minimal) electrical requirements. Any electrical requirements (e.g., to operate a fan or electronic controls) may be provided by a more typically sized BESS (e.g., smaller battery packs) that can be found in many portable electronic devices. It is also understood that storing energy as heat, when the final use-case is heat, is more efficient than storing energy as electricity and then converting the stored electricity to heat at a later time.
[0126] When paired with a control system, the TESS can be charged and deliver heat to take advantage of more affordable electric utility rates that are offered in some locales (e.g., off-peak rates or tariffs). The TESS is also amenable to be paired with renewable energy sources to take advantage of peak electricity generation when natural energy sources are abundant (e.g., sun, wind, water, and/or geothermal energy), and the heat can be stored for use later when such sources are scarce. When utilities (power grid) cannot use the electricity generated from wind, the turbines are forced to shut down, even though wind conditions may be amenable to continue generating power. The use of TESS may beneficially enable the use of this extra energy, further allowing the utilities to balance electricity generation. When a residential photovoltaic (PV) system is generating more electricity than required by a home, the excess electricity is fed back into the grid, and the utilities do not pay back for this excess electricity at a competitive price. If a better use of generated power is found, the users may continue to reap the benefits of their PV system. Storing the excess electricity in the TESS, therefore, would allow the users to access such excess power as heat.
[0127] Converting electricity into heat and storing this heat for future use in the TESS is both more energy-efficient and economical when the intended use is to provide the level of heat that a fireplace is scaled to for an extended period of time (e.g., from 12 to 48 hours). Beneficially, heat stored in the TESS may also be released from the system in a manner to better simulate an authentic fire experience for the users. Using the TESS may beneficially simulate a more realistic ember/fuel bed and recreate the heat radiating from a gas, or wood, fireplace, thus providing a different heating experience from that of using only the fireplace.
[0128] An experience that is pleasing to the users for relaxation or social gathering that is not typically offered by space-heating products (e.g., storage heater or home space heaters) can be created by combining together the elements of thermal storage and adjusted heat output/delivery in an aesthetic fire feature that incorporates the simulation of a fire experience.
[0129] The TESS may also provide users with a more economical manner to generate heat, thus saving on energy costs. Many utilities offer, are in the process of offering, or will be requiring residential utility customers to implement, on-peak/off-peak rate plans in order to better balance the supply and demand of electricity generated on the utility grid. With efforts to drive electrification, decarbonize energy generation, and reduce greenhouse gas emissions, manufacturers may more readily design products that better align to such trends by implementing the fireplace with the TESS. An electric fireplace utilizing TESS technology allows users to purchase electricity during off-peak rates that can be used to charge the TESS (e.g., overnight), and the stored energy can be released as heat during times of the day when electricity rates are higher, thus beneficially allowing users to reduce the demand for electricity, for example by reducing the amount of electricity that is used on the HVAC system for the home in real time and relying more on the stored energy that was purchased more cheaply.
[0130] Freeing the electric fireplace from a dedicated electrical requirement also beneficially allows the fireplace to not be attached to a wall and thus not requiring a dedicated electrical connection, for example to a power outlet. A thermal battery or TESS allows the fireplace to be installed in different spaces throughout the home or outdoors, as well as enabling portability of the product, or the fireplace system. For example, the fireplace system may be charged electrically for a time and thereafter unplugged to be used independently. Weight of the TESS (such as weight of the heat storing material) would impact portability; therefore, scaling the heating experience and selection of the heat storing material would be important to enable easier transport of the product.
[0131] Numerous characteristics and advantages have been set forth in the preceding description, including various alternatives together with details of the structure and function of the devices and/or methods. Moreover, the scope of the various concepts addressed in this disclosure has been described both generically and with regard to specific examples. The disclosure is intended as illustrative only and as such is not intended to be exhaustive. It will be evident to those skilled in the art that various modifications may be made, especially in matters of structure, materials, elements, components, shape, size, and arrangement of parts including combinations within the principles of the disclosure, to the full extent indicated by the broad, general meaning of the terms in which the appended claims are expressed. To the extent that these various modifications do not depart from the spirit and scope of the appended claims, they are intended to be encompassed therein.
