GB2582887A

GB2582887A - A heating panel

Info

Publication number: GB2582887A
Application number: GB1817658.6A
Authority: GB
Inventors: Luke Raymond
Original assignee: SOLAR READY Ltd
Current assignee: SOLAR READY Ltd
Priority date: 2018-10-29
Filing date: 2018-10-29
Publication date: 2020-10-14
Also published as: GB201817658D0

Abstract

A heating panel 100 has a thermal mass 120 and an electric heating element 140. One or more conduits 128 for containing a phase change material 130 extend through the thermal mass. The electric heating element heats the thermal mass, and the phase change material, and the phase change material undergoes a phase transition to store thermal energy for subsequent release. The thermal mass may be made out of a plurality of interconnected blocks of material such as soapstone and the conduits may be defined by grooves in one surface of one block being enclosed by another surface of another block. The panel might also have a means for triggering the phase change material to transition from one phase to another such as an ultrasonic transducer. Also claimed is an item of furniture, such as a door (500, fig 17), table or desk, including said heating panel.

Description

A Heating Panel

Field of the Invention

The present invention relates to a heating panel. More specifically the present invention relates to a heating panel comprising energy storage means which may be incorporated into items of furniture.

Background to the Invention

Offices and other buildings such as homes or schools are typically heated by radiators or other heat exchangers which are supplied with hot water by a central heating system. There is increasing pressure to reduce the costs and energy demands of heating such buildings.

One way of reducing costs of heating is to build new offices and dwellings using better quality materials; and to insulate buildings better than previously; and to employ use of high quality double glazing in order to reduce heat loss, thereby improve heat retention in buildings.

Improved heating appliances and heat recovery systems have been developed that are more efferent than traditional convection heater. Mostly these have relied upon burning fossils fuels (gas, oil or wood pellets) in order to provide heat for a building. However, all these fuels are carbon based and so burning them has added to the so-called carbon footprint of a dwelling or business premise.

An object of the present invention is to provide an improved means for heating a building.

Summary of the Invention

According to a first aspect of the invention there is provided a heating panel comprising: a thermal mass; one or more conduits for containing a phase change material which extend through the thermal mass; and an electric heating element for heating the thermal mass and the phase change material within the conduits.

In use, the electric heating element may be used to heat the thermal mass and the phase change material contained therein (this may also heat the remainder of the heating panel, and/or any item of furniture and/or environment within which the heating panel is located). The heated thermal mass and the phase change material may then store heat for subsequently heating the panel, and/or any item of furniture and/or environment within which the panel is located, typically when the electric heating element is inactive.

A phase change material (PCM) is a substance that absorbs a large amount of energy when undergoing a phase transition from a first phase to a second phase, and releases the energy when transitioning from the second phase to the first. A phase change material may therefore store larger amounts of thermal energy than a conventional thermal mass.

In use, the electric heating element may heat the phase change material within the conduits of the thermal mass to a transition temperature, thereby causing the PCM to undergo such a phase transition from a first phase to a second phase. During the phase transition PCM may absorb a large amount of energy without a significant increase in temperature. The phase change may subsequently be reversed when the electric heating element is inactive, releasing the energy stored within the PCM to heat the panel.

In some embodiments, the thermal mass and/or the phase change material may also provide cooling, by absorbing excess heat in their environment, thereby acting as cool thermal masses. For example, the panel may provide cooling during the hottest hours of the day by absorbing heat, which may be subsequently released (for example, during the cooler hours of the night).

Panels are typically flat and relatively thin structures which advantageously have a relatively large surface area to volume ratio. This allows the heating panel to more effectively heat an item of furniture and/or an environment within which it is located. In some embodiments the panel may be substantially cuboid. In alternative embodiments the panel may be curved, for example so as to fit onto or into some other structure.

In some embodiments, the panel may consist of a substantially rigid panel-shaped thermal mass, and other components which are attached to or formed on the exterior of the thermal mass, or which are partially or entirely embedded within the thermal mass.

For example, the electric heating element may be an electric heating film formed on one or more exterior surfaces of the thermal mass, the heating element may be located within a recess in the surface of the thermal mass such that it is flush with the outer surface of the thermal mass, or the heating element may be embedded within the thermal mass.

The rigid panel shaped thermal mass may define the shape and dimensions of the panel, and may define part or all of the exterior of the panel. The thermal mass may be a single body, or may comprise a plurality of bodies interconnected such that they form a rigid panel shaped structure.

In other embodiments the panel may comprise a casing which may contain the thermal mass and the electric heating element, and which may contain other components comprised by the heating panel. The casing may be rigid and may define the shape and dimensions of the panel.

Some or all of the other components of the heating panel may be held in a fixed arrangement with respect to each other by the casing, and/or may be located within a cavity defined by the casing. Such a cavity may be substantially filled by the other components of the heating panel.

In some embodiments, the panel may be comprised by an item of furniture. The components of the heating panel may be held together, in a fixed arrangement with respect to each other, and/or in a panel shape by the item of furniture.

In some embodiments, the item of furniture may comprise a panel shaped cavity which may contain, and may be substantially filled by the components of the heating panel. In other embodiments, where the panel is a substantially rigid body (for example, where the panel has a rigid casing, or consist of a rigid thermal panel with other components embedded therein), the panel may define a portion of the exterior of the item of furniture.

The components of the panel may be held together in a fixed arrangement by being held within a casing, by being held within a cavity comprised by an item of furniture, by one or more connectors, by one or more adhesives, and/or by embedding components within the thermal mass.

A thermal mass is typically a body of material capable of absorbing, storing and releasing thermal energy. The thermal mass comprised by the heating panel preferably comprises one or more bodies or blocks of material with high specific heat capacities and high density. The greater the density and the specific heat capacity of a block of material the greater the amount of thermal energy it will absorb or release when undergoing a given temperature change.

In embodiments where the thermal mass comprises a plurality of bodies or blocks of material, some, or all of the plurality of blocks may be interconnected and may be in thermal communication with each other such that heat is conducted from one body or block of the thermal mass to another.

The material comprised by the thermal mass may also have a relatively low thermal conductivity. This may ensure that after the thermal mass has been heated (for example, by the electric heating element, or by the phase change material undergoing a phase transition during which heat is released) the thermal mass rereleases heat into its surroundings relatively slowly and does not rapidly equalise in temperature with its surroundings.

The thermal mass is preferably solid and preferably rigid. The thermal mass may be generally or substantially panel shaped and/or cuboid.

Other components of the heating panel may be embedded in, formed on, or connected to the thermal mass, and/or may be held with the thermal mass within a casing comprised by the heating panel or a cavity comprised by an item of furniture comprising the thermal panel.

In preferred embodiments the thermal mass comprised by the heating panel consists substantially of a single material. The thermal mass may comprise a single body or block of the single material or may comprise multiple interconnected bodies or blocks of the material.

In alternative embodiments, the thermal mass may comprise multiple blocks or bodies, each formed from different materials, may comprise a single block or body which itself comprises a plurality of materials, or may comprise a plurality of blocks or bodies one or more of which may be formed a plurality of different materials. The multiple blocks or bodies may be held or connected together so as to define a single panel or cuboid shaped structure.

In some embodiments, multiple blocks or bodies of material which are comprised by the thermal mass may be separated by other components of the heating panel (such as electric heating elements, which may be electric heating films), or by spacers which space the bodies or blocks apart to provide spaces for other such components.

In preferred embodiments, the thermal mass comprises rock (such as limestone or soapstone) and/or plaster of Paris. In further preferred embodiments the thermal mass substantially consists of rock (such as limestone or soapstone) and/or plaster of Paris.

The heating panel comprises one or more conduits for containing a phase change material which extend at least partially through the thermal mass. In some embodiments the heating panel may comprise a plurality of conduits for containing a phase change material which extend through the thermal mass. The plurality of conduits may be interconnected.

In use, the conduits may contain a phase change material and may act as a heat exchanger between the phase change material contained therein and the thermal mass within which they are embedded. Therefore, as the thermal mass is heated (for example, by the electric heating element) heat may be transferred to the PCM. The PCM may be heated until it undergoes a phase transition, thereby storing heat for subsequent release.

Holding the phase change material within one or more conduits within the thermal mass may advantageously provide a large surface area boundary between the thermal mass and the PCM. This may accelerate the rate at which heat is conducted to the PCM from the thermal mass and vice versa. The one or more conduits may be only partially filled with the PCM, this may provide volume for the PCM to expand into when undergoing a phase transition.

In some embodiments, one, some, or all of the one or more conduits may be, or may comprise, one or more pipes at least partially embedded within the thermal mass.

The pipes may be formed from a different material to the thermal mass. Preferably, the pipes are formed from a material is impervious to the phase change material (in at least the phases it will occupy over the range of the operating temperatures of the panel) and/or are formed from a material with a high thermal conductivity. In some embodiments, the pipes may be formed from metal and/or plastic. In other embodiments the pipes may be or may comprise flexible tubing.

Preferably, at least a partial length of at least one of the one or more pipes is embedded within the thermal mass such that the entirety of the circumference is in contact with the material of the thermal mass. In preferred embodiments, the majority of, or substantially all of, the length of each of the one or more pipes is embedded within the thermal mass such that the entirety of the circumference is in contact with the material of the thermal mass. This may lead to improved thermal conductivity between the thermal mass and the phase change material.

Such an arrangement may be constructed by placing the PCM carrying pipes within a mould for the thermal mass as the thermal mass is set (for example, in embodiments where the thermal mass is formed from plaster of Paris).

Alternatively, partial lengths of, the majority of, or substantially all of one, some or all of the one or more pipes may be located within elongate holes or tunnels formed through, and/or grooves formed in the surface of, the thermal mass and/or blocks of material comprised thereby. Within the holes, tunnels or grooves the surface of the pipes may not be in complete contact with the thermal mass. Such an arrangement may facilitate the construction of the heating panel, for example by allowing the pipes to be removed from the thermal mass.

In some embodiments, grooves formed in the surface of bodies or blocks of material comprised by the thermal mass may enclosed by other bodies or blocks of material comprised by the thermal mass so as to define elongate holes or passageways extending through the thermal mass.

In some embodiments, one, some, or all of the one or more conduits extending through the thermal mass may comprise elongate holes or tunnels extending through the thermal mass. All or a portion of the length of one, some, or all of the one or more conduits may be elongate holes or tunnels extending through the thermal mass. Therefore, the conduits may be defined and bounded by the thermal mass.

These elongate holes or tunnels may be defined by enclosed grooves formed in the surface of bodies or blocks of material comprised by the thermal mass as described above. In such an arrangement, grooves in a block of material may be fully enclosed along its length by another block of material (although they may be open at their ends) such that PCM cannot escape or leak from the defined elongate hole or tunnel when the it is in a liquid or gaseous phase.

In such embodiments the thermal mass is preferably formed from a material impervious to the phase change material in the phases it will occupy over the range of temperatures at which the heating panel operates.

In conduits (or lengths thereof) which are defined and bounded by the thermal mass, the phase change material may be in direct contact with the thermal mass, this may increase thermal conductivity between the PCM and the thermal mass. Such an arrangement may also simplify construction of the heating panel.

In some embodiments, all of the length of all of the one or more conduits extending through the thermal mass are elongate holes or tunnels through one or more bodies or blocks of material comprised by the thermal mass.

In some embodiments, the thermal mass comprises a plurality of parallel conduits. The parallel conduits may have substantially equal lengths and may have ends which are colinear on lines perpendicular to the lengths of the conduits. The plurality of parallel conduits may be interconnected by conduits which may extend perpendicular to the parallel conduits. These conduits may interconnect the ends of the parallel conduits. For example, in some embodiments the thermal panel may comprise multiple conduits interconnected in a comb shaped or ladder shaped arrangement.

In some embodiments the thermal mass may comprise multiple separate networks of interconnected conduits, for example a panel may comprise a pair of interleaved comb shaped networks of interconnected conduits.

One, some, or all of conduits may be parallel to one or more planar surface of the thermal mass, and/or of the panel.

One, some or all of the conduits may be substantially tubular along all or a part of their lengths. In some embodiments the conduits may be or may comprise cylindrical portions with circular cross sections. In other embodiments the conduits may have substantially polygonal cross sections, for example square or rectangular cross sections.

In some embodiments, one or more conduits may extend to or out of edge one more bodies or blocks of material comprised by the thermal mass. In some embodiments these conduits may interface with or connect to conduits in other bodies or blocks of material comprised by the thermal mass so as to provide a conduit which extends through multiple blocks or bodies of material comprised by the thermal mass. In some embodiments, these conduits may extend to or out of the edge of the thermal mass. These conduits may provide an inlet or outlet via which the phase change material may enter or exit the conduit, or may interconnect the conduit with additional conduits comprised by other systems, or by an item of furniture comprising the heating panel.

Such a conduit may comprise a valve to open or close the conduit, for example to permit, prevent, or control the flow of a phase change material into or out of the conduit.

The conduits (such as pipes) may define an impermeable container within which the PCM (which may be in a liquid phase in use) is contained. In some embodiments, the boundaries of the conduits may be coated with an impermeable layer, and/or other components of the heating panel (such as the electric heating element) may be covered with impermeable protective layers.

In a particularly preferred embodiment, the thermal mass comprises a plurality of generally cuboid and panel shaped blocks of material which are arranged face to face (for example, within a casing, or within a cavity within an item of furniture). Each block comprises a plurality of parallel grooves extending across the width of one or both of the large faces of the panel shaped block of material.

The panel shaped blocks of materials are placed face to face such that the elongate openings of the grooves of each panel are covered and enclosed by the surface of another of the panels thereby defining elongate conduits extending through the thermal mass from first sides of the blocks of material to second opposite sides of the blocks of material.

The thermal mass further comprises a pair of additional blocks of material each of which are fixed to the one of the sides of the blocks of material between which the elongate conduits extend. The additional blocks of material each comprise an elongate groove, the openings of which fit onto the sides of the blocks of material between which the elongate conduits extend, such that the grooves define an enclosed conduit which interconnects the conduits extending through the other blocks of material.

In some embodiments the thermal mass may comprise, or may be formed from one or more fire resistant materials. This may allow the heating panel to be comprised by fire resistant items of furniture such as fire doors. Alternatively, or additionally, layers of fire-retardant film may be formed on the thermal mass, the interior or exterior of the casing, between blocks of material comprised by the thermal mass, and/or on the interior of a cavity within which the heating panel is located.

One or more conduits which extend through the thermal mass are for containing a phase change material. As described above, a phase change material (PCM) is a substance that absorbs a large amount of energy when undergoing a phase transition from a first phase to a second phase, and releases the energy when transitioning from the second phase to the first.

In use the PCM may be heated when the electric heating element is active until it undergoes a phase transition, during which it may absorb a large amount of thermal energy without significantly increasing in temperature. This phase transition may subsequently be reversed (for example, when the temperature of the PCM and/or its surroundings decreases, or when a phase change of the PCM is triggered by a triggering means comprised by a panel, or an item of furniture comprising the panel) and the thermal energy stored within the PCM may be released, thereby heating the panel and its surroundings.

In preferred embodiments, the PCM transitions from a first phase to a second phase when heated to a transition temperature. The transition temperature is typically greater than room temperature, but less than or equal to the temperature to which the heating panel may be heated by the electric heating element. For example, the transition temperature may be greater than 40°C, greater than 45°C, or greater than 50°C; the transition temperature may be less than 65°C, less than 60°C, or less than 55°C.

In some embodiments, the phase change material may transition from the second phase to the first phase when the temperature of the PCM falls below some threshold temperature, which may be the same as the transition temperature.

In other preferred embodiments, the second phase of the phase change material may be a metastable phase. In these embodiments, unless a phase change is triggered by some other means (for example a vibration) the PCM may remain in the second phase when the PCM is cooled below the transition temperature, and preferably remains in the second phase when the PCM cools to and/or below room temperature. More preferably the PCM remains in second phase even when it is cooled below 10°C, or below 0°C. A metastable state may allow the heating panel to operate as a latent heat storage unit.

The first phase is preferably a solid or crystalline phase. Alternatively, the first phase may be a liquid or gaseous phase. The second phase (which may be a metastable phase) is preferably a liquid or amorphous phase. Alternatively, the second phase may be a solid or gaseous phase.

In some embodiments the phase change material may be an organic phase change material. Organic PCMs may be derived from lipids such as unsaturated vegetable oils. For example, the PCM may be derived from flax oil or linseed oil. Organic PCMs may also be derived from other organic materials such as paraffin.

In other embodiments the phase change material may be a salt hydrate phase change material. For example, the PCM may be a sodium acetate solution. In some embodiments the PCM may be a eutectic PCM.

Some PCMs may transition from their second phase (which may be a metastable phase) to their first phase when triggered to do so (in addition to, or alternatively to transitioning when the PCM falls below some threshold temperature).

For example, in embodiments where the first phase of the PCM is a crystalline phase (such as where the PCM is a sodium acetate solution), a phase transition from the second phase (the crystalline phase) to the first phase may occur when a nucleation centre is created within the PCM, for example by flexing a metal disk located within the phase change material. In other embodiments, such as where the PCM is an organic PCM, the phase transition may be triggered when all or a portion of the PCM is compressed, vibrated, and/or has friction, an electric current, an electric field, and/or a magnetic field applied thereto.

The heating panel may comprise one or more triggering means for triggering a transition of the phase change material from its second phase to its first phase. The triggering means may be located within or adjacent the thermal mass and/or the phase change material carrying conduits.

The triggering means may trigger a phase transition of the PCM from the second phase to the first phase automatically (for example, at predetermined times, or at predetermined temperatures), or in response to one or more control signals (for example, which are received when a heating panel is manually activated by a user, received from a central heating system, or are received when one or more sensors detects a predetermined condition at which the phase transition occurs, for example when a thermometer detects a temperature below a predetermined threshold).

In some embodiments the triggering means may trigger a phase transition by compressing, vibrating, applying friction to, applying an electric current to, applying an electric field to, and/or applying a magnetic current to all or a portion of the PCM. In some embodiments, the triggering means may trigger a transient by an ultrasonic vibration, for example, the triggering means may be, or may comprise ultrasonic transducer such as an ultrasonic transmitter. Vibrating or ultrasonic triggering means may operate at 27 Hz and/or may operate at 7 Hz.

Using a triggering means may advantageously allow the heat stored within the phase change material in its second phase to be released on demand.

In some embodiments, multiple distinct phase change materials may be contained by conduits extending through the thermal mass. For example, sperate conduits, or separate interconnected networks of conduits may hold different PCMs.

The phase change material may substantially fill the volume of the conduits extending through the thermal mass in one, some or all of the phases which it occupies during normal operation of the heating panel (for example over the range of operating temperatures of the thermal mass).

In preferred embodiments the heating panel comprises a phase change material which is held within the one or more conduits extending through the thermal mass.

In some embodiments the heating panel may comprise multiple phase change materials held within the one or more conduits extending through the thermal mass. The one or more phase change materials comprised by the heating panel may be the same material, or may be different materials and may have any of the features described above.

In embodiments where the heating panel comprises multiple separate phase change materials, the multiple phase change materials may transition from their second states to their first states at different temperatures, or in response to different triggering means. The heating panel may separate triggering means for triggering separate phase change materials.

The heating panel comprise an electric heating element for heating the thermal mass and for heating a phase change material held within the conduits.

In some embodiments, the heating panel may comprise a plurality of electric heating elements, the plurality of heating elements may be independently activatable, and/or may be arranged in different locations within the heating panel (for example, so as to provide directional heating on different sides of the panel, and/or of an item of furniture comprising the panel).

The electric heating element may be a heating film. In some embodiments, the item of furniture may comprise a plurality of heating films which may be arranged parallel to each other within a plurality of parallel planes. In some embodiments, one or more heating films may cover part, or substantially all of one or more walls or surfaces of the thermal mass, and/or of the interior of a casing or cavity within which the heating panel is located.

In some embodiments, the heating panel (or an item of furniture comprising the thermal panel) may comprise an electrical storage unit -such as a battery (which may be rechargeable, for example a rechargeable lithium ion battery) -and/or may comprise means for connecting with an external power source -such as a power cable, plug, and/or socket for connecting with an external power socket. Alternatively, or additionally, the heating panel (or the item of furniture comprising the heating panel) may be connected to and/or integrated with an external electricity supply, such as a mains circuit, or an external generating means such as a solar panel. The electric heating element may be powered by any of these features.

The electric heating element may be a DC low voltage heating element, which may be a DC low voltage heating film. The low voltage heating element may be 24v DC element.

The one or more electric heating elements comprised by a thermal panel may be formed on the exterior of, and/or embedded within the thermal mass. This may increase the efficiency with which the electric heating elements heat the thermal mass.

In embodiments where the thermal mass comprises a plurality of bodies or blocks of material, electric heating elements (such as electric heating films) may be located intermediate the multiple bodies or blocks of material (for example, in gaps provided by spacers intermediate the blocks of material). This may allow the heating elements to more effectively heat multiple blocks comprised by the thermal mass.

In some embodiments, carbon silver oxide or graphite silver oxide past may be provided adjacent the electric heating element.

According to a second aspect of the invention there is provided an item of furniture comprising a cavity, and a heating panel according to the first aspect of the invention located within the cavity.

In use the item of furniture (which may for example, be a door, a desk or some other worksurface), may provide heating to an environment within which it is located in the same manner as the heating panel described above. This may advantageously allow a heating means to be located within the centre of an environment to be heated (such as a building, or room).

In some embodiments, the cavity may be an indentation in, or an aperture through the item of furniture. In a preferred embodiment the cavity is an enclosed space within the item of furniture.

In embodiments, wherein the cavity is enclosed, a portion of the item of furniture may be displaceable so as to allow access to the cavity. This displaceable portion may comprise one or more hatches, doors, drawers, removable and/or displaceable panels, or any combination thereof.

The cavity may be proximate and/or adjacent to the exterior of the item of furniture. This may increase the efficacy of heating provided by the heating panel comprised by the item of furniture. In some embodiments the cavity and the heating panel contained therein may be proximate and/or adjacent an exterior surface of the item of furniture so as to provide greater heating in a specific direction.

In embodiments where the cavity is substantially cuboid and/or comprises a substantially planar wall, the cavity may be located adjacent to and/or parallel to a substantially planar exterior surface of the item of furniture.

The heating panel ideally substantially fills the volume of the cavity. In some embodiments the item of furniture may comprise a plurality of heating panels according to the first aspect of the invention, which may be located within the same cavity, or a plurality of separate cavities.

Preferably, the item of furniture performs another function in addition to providing heating, this function may be practical and/or aesthetic. For example, the item of furniture may be a door, a table, a chair, a work surface, a desk, a hatch, a shelving unit, a storage unit, a stair tread, a stair riser, a shutter, or a decorative wall panel or frame.

In some embodiments, the portions of the cavity which are not filled by the heating panel may be filled with other objects such as spacers or insulation located on one or some of the sides of the heating panel. In preferred embodiments, the heating panel substantially fills the volume of the cavity. The heating panel may be in contact with the walls of the cavity so as to increase the conduction of heat from the heating panel to the item of furniture and its environment..

In some embodiments, the item of furniture, the heating panel, and/or the thermal mass may be fire-retardant. This may allow the item of furniture (or a stand-alone heating panel) to act as a fire barrier. For example, an item of furniture comprising a heating panel may be a fire door.

In some embodiments, a heating panel according to the first aspect of the invention, or an item of furniture according to the second aspect of the invention may comprise a control means, in other embodiments the heating panel, or the item of furniture or components thereof may be connected (wirelessly and/or via a connection comprising one or more electrical conductors) with an external system which may control all or some of the components of the heating panel.

In some embodiments, a control means comprised by the heating panel or the item of furniture comprising a heating panel may automatically control the heating of the heating panel in response to preprogramed settings and/or internal and/or external stimuli. The control means may automatically activate and/or deactivate the electric heating element, and/or a triggering means comprised by the heating panel. Factors which may determine the behaviour of the control means may include the detected temperature of the heating panel or the item of furniture, the detected temperature of the environment within the which the heating panel or the item of furniture is located, the time, any desired temperature or heating plan provided to the heating panel or the item of furniture (for example, by a user, or by a central heating system), and/or the current electrical cost rates.

Alternatively, or additionally, the control means may allow the heating panel (which may be comprised by the item of furniture) to be controlled directly by a user. A user's instructions may override any automatic behaviour of the heating panel or components comprise thereby. In some embodiments, the control means may comprise manual controls (for example, controls located on the surface of the heating panel of a item of furniture comprising the heating panel). Alternatively, or additionally, the control means may be configured to receive wireless control signals from an external control system, such as a remote control, a user's smartphone (for example), a system on which virtual assistant (such as an Amazon Alexa (RTM) intelligent personal assistant) is running, or a central heating system.

In other embodiments, the heating panel or the item of furniture may not comprise a control means, and may be connected to an external controlling system (which may be a dedicated controlling system, or some other system such as a central heating system). This connection may be made wirelessly, or via one or more wires, cables or other direct electrical connections, or pathways of electrical conductors.

In some embodiments, the heating panel, or item of furniture comprising a heating panel may comprise one or more sensors, for example the device may comprise one or more thermostats, humidity sensors, clocks, proximity sensors and or timers. Detections or signals produced by these sensors may be used to control the heating panel, components thereof, or other components of the item of furniture.

The electrical heating element, the thermal mass, and the remainder of an item of furniture within which they are located are preferably in physical and/or thermal communication with one another.

In some embodiments, the electrical heating element may be activated, and/or the rechargeable battery comprised by the item of furniture or the heating panel may be charged automatically when electrical rates are low.

In some embodiments, the heating panel or the item of furniture comprising a heating panel, may comprise one or more light emitting diodes (LED) lights and/or other status indicators. The LED light or lights may be activated or deactivated and/or may alter in colour in response to whether the electric heating element, and/or heat exchanger are active, on the phase of a PCM comprised by the heating panel, and/or other detected factors, such as the temperature of the heating panel, the item of furniture, or their surroundings. In other embodiments, the item of furniture may comprise one or more motion sensors which may control one some or all of the LED lights.

In some embodiments, a heating panel according to the first aspect of the invention, or an item of furniture according to the second aspect of the invention may comprise one or more ducts for air to pass through the heating panel of the item of furniture. In preferred embodiments the heating panel or item of furniture comprises a plurality of such ducts.

In use, air within the ducts comprised by a heating panel, or an item of furniture which comprises a heating panel, may be in thermal conduct with the heating panel, and/or the thermal mass and/or phase change material comprised by thereby. The ducts may act as a heat exchanger between the air and the thermal mass and/or PCM of the heating panel.

Depending upon the temperature differential between the air and the thermal mass and/or PCM, the air may be cooled or heated by the transfer of thermal energy between the air and the heating panel. The ducts may therefore allow air to be more effectively heated or cooled by the heating panel.

In preferred embodiments each of the one or more ducts may extend through the item of furniture from a first vent to a second vent. In use air may enter the heating panel or item of furniture through one of the vents, and may exit through the other vent after being heated or cooled by its thermal contact with the heating panel. In some embodiments, the first vent may be lower than the second vent, for example the first vent may be in a lowermost, and/or downwards facing surface of the heating panel or item of furniture (for example the bottom edge of a door), and/or the second vent may be in an uppermost, or upwards facing surface of the heating panel or item of furniture (for example the top edge of a door).

In use, the heating or cooling of the air within the ducts may lead to a change in pressure of the air within the ducts, which may lead to a flow of air through the conduits being established due to convection, this may lead to a continuous flow of air being drawn into the duct (for example through a first vent), being heated or cooled, and subsequently exiting the duct (for example through a second vent), this may continue until the air surrounding the heating panel or item of furniture has equalised in temperature with the heating panel so that no further convection occurs.

Alternatively, or additionally, air may be driven or drawn through the one or more ducts, for example by one or more air pumps and/or fans, which may be comprised by the heating panel or item of furniture.

In some embodiments, air within the ducts may cooled to its dew point such that it becomes saturated with water vapour. The dew point may be varied to achieve this.

In some embodiments, the item of furniture may further comprise an air conditioning unit which may operate in conjunction with the other components of the item of furniture and which may be controlled by the same control means or system.

In a particularly preferred embodiment, the item of furniture is a door. Electrical a connections between the door and external systems may be made by flexible cables or other conductors between the door and the door frame, or by separable connections which are only complete when the door is closed (for example, which charge a rechargeable battery comprised by the door). In embodiments comprising ducts through which air passes through the item of furniture, the air may enter or exit though vent apertures formed in one or both faces of the door, and/or may enter or exit through vent apertures formed in the rim of the door (for example in the top or bottom surfaces of the door), which may be blocked when the door is closed. The door may comprise a sensor which may detect whether the door is open or closed, the detection of which may be used by a control means comprised by the door.

In some embodiments, the door may be configured to give off more heat from one face, for example, the cavity may be formed closer to one face, the electric heating element may be formed closer to one face, and/or one faceward wall of the cavity may be more thermally insulating than the other. In some embodiments, a layer of thermally insulating material may be formed on one face of the door, or between one face of the door and the cavity and heating panel.

In some embodiments, the door, and/or the door frame may comprise an air curtain.

In other preferred embodiments, the item of furniture may be a desk or table, the cavity and/or the heating panel may be substantially horizontal and may be formed in, under, and/or substantially parallel to the horizontal planar surface of the table or desk. In some embodiments, the desk or table may comprise sensors for detecting whether or not objects have been placed on the desk or table and/or for detecting whether one or more people are sitting at the desk or table.

Preferred embodiments of the invention will now be described, by way of example with reference to the Figures, in which:

Brief Description of the Figures

Figure 1 is a cross-sectional view of a first heating panel according to the first aspect of the present invention; Figure 2 is an overall view of a thermal mass for a heating panel according to the first aspect of the present invention; Figure 3 is an overall view of a first component of the thermal mass of Figure 2; Figure 4 is a side view of the first component of Figure 3; Figure 5 is an overall view of a second component of the thermal mass of Figure 2; Figure 6 is an overall view of a second heating panel according to the first aspect of the present invention; Figure 7 is an overall view of a mould for casting a thermal mass for the heating panel of Figure 6; Figure 8 is an overall view of the mould of Figure 7 with a first network of conduits located therein; Figure 9 is an overall view of a thermal mass for the heating panel of Figure 6 being removed from the mould of Figures 7 and 8; Figure 10 is an overall view of the thermal mass of the heating panel of Figure 6 after it has been removed from the mould of Figures 7 and 8; Figure 11 is an overall view of a first door according to the second aspect of the present invention; Figure 12 is an overall view of the door of Figure 11 with an outer panel removed allowing access to the cavity; Figure 13 is an overall view of the door of Figure 11 with an outer panel and the thermal mass removed; Figure 14 is an overall view of an outer panel and the central panel of the door of Figure 11; Figure 15 is an overall view of a heating panel arranged within the central panel of the door of Figure 11; Figure 16 is a diagrammatical view of the door of Figure 11; Figure 17 shows vertical and horizontal cross sections of the door of Figure 11; Figure 18 is an overall external view of the door of Figure 11 within a frame; Figure 19 is an overall view of a pair of desks according to the second aspect of the present invention; Figure 20 is an overall view of a room with a pair of desks and a door according the second aspect of the present invention; Figure 21 is an overall view of a room with a pair of desks according to the second aspect of the present invention; and Figure 22 is a plan view of a building containing desks according the second aspect of the present invention.

Detailed Description of the Figures

Referring to the Figures generally there are shown embodiments of heating panels and items of furniture according to the first and second aspects of the present invention.

Figure 1 shows a first heating panel 100 according to the present invention, and figures 2 to 5 show a thermal mass for a heating panel according to the present invention which is of similar construction to the thermal mass comprised by the first heating panel of Figure 1.

Figures 6 to 10 show a second heating panel according to the present invention, and a mould and method for the construction thereof.

Figures 11 to 18 show a door according to the second aspect of the present invention.

Figures 19 to 21 show sitting and standing desks according to the second aspect of the present invention.

Figure 22 shows a plan view of a building with a wing heated by desks according to the second aspect of the present invention.

Figure 1 shows a cross-sectional view through the width of a cuboid heating panel 100. The heating panel 100 comprises a thermal mass, which consists of four blocks of material arranged in pairs with conduits 128 extending through them, a phase change material 130 located within the conduits, three sheets of electric heating film 140, a plurality of spacers 150, a plurality of ultrasonic triggering means 160 and a casing 110 which contains the other components, The casing 110 is a cuboid box of length 512mm, width 262mm, and depth 39mm, which encloses a cuboid cavity of length 500mm, width 250mm, and depth 27 mm. The casing is formed of 6mm thick layers of fire retardant decorative board. The plane of the cross-sectional view being orthogonal to the width of the The thermal mass consists of two pairs of interlocking blocks 120 of soapstone. The pairs of blocks 120 of soapstone having combined lengths of 500mm and depth-wise thicknesses of 12mm. Each block 120 comprising central flat portion 122 of length 440m and thickness 6mm; the central flat portion 122 being intermediate two end portions 124 comprising mating protrusions or recesses. Each of the pairs of blocks 120 are interconnected such that a face 126 of the central flat portion 122 of one of the blocks 120 is coplanar with a face 126 of the central flat portion 122 of the other block 120.

Each of the coplanar faces 126 of each pair of blocks 120 has a plurality of parallel grooves 128 formed therein, which extend width-wise across the coplanar faces 126 of the blocks 120. Each groove 128 has an elongate opening in the coplanar face 126 and a pair of smaller end opening in the sides of the blocks 120. The elongate opening of each groove 128 each of the blocks is covered by an un-grooved portion of the coplanar face 126 of the other interlocking block, such that the grooves 128 are enclosed along their length and form conduits.

The ends of the grooves may be closed, for example by the casing 110, or may be interlinked, for example by one or more lengthwise extending conduits which run along the sides of the blocks 120 material. These lengthwise extending conduits may be comprised by additional blocks of material, as in the thermal panel 200 shown in Figure 2.

Each of the conduits defined by the enclosed grooves 128 is substantially filled with the phase change material 130. The phase change material is a linseed oil derived organic PCM which undergoes a phase transition from a first solid phase to a second liquid phase when heated from room temperature to some higher temperature.

The second liquid phase is metastable, and as such the PCM 130 may remain in the second liquid phase even when the PCM 130 and the surrounding thermal mass cool to room temperature or lower. The PCM 130 may be triggered to undergo a phase transition from the second liquid phase to the first solid phase by an ultrasonic vibration.

As such each of the blocks of material 120 comprised by the thermal mass has a plurality of ultrasonic transducers 160 embedded within the non-coplanar faces of each pair of interconnected blocks. In use, these ultrasonic transducers may be activated to produce an ultrasonic vibration in the blocks of material 120, causing the PCM 130 to undergo a phase transition and to release stored thermal energy, thereby heating the thermal mass and the heating panel. Activating the transducers 160 and releasing the stored energy requires significantly less electricity than using the layers electric heating film 150.

The heating panel 100 further comprises three layers of spacers which are located intermediate the upper wall of the casing 110 and a first pair of interconnected blocks 120, intermediate the first pair of interconnected blocks 120 and the second pair of interconnected blocks 120, and intermediate the second pair of interconnected blocks 120 and the lower wall of the casing 110.

The spacers 150 provide 1mm thick gaps between casing and each of the pairs of interconnected blocks 120, and between the two pairs of interconnected blocks, and fix the locations of the blocks within the cavity of the casing 110. Each gap contains a layer of electric heating film 140 in a plane substantially orthogonal to the depth of the panel. The layers of electric heating film are 24v DC heating film.

The gaps are also filled with a thermal past of carbon silver oxide, or graphite silver oxide.

In use, the layers of electric heating film 140 may be activated to heat the heating panel 100, its surroundings, and the thermal mass and PCM 130 comprised thereby. This may advantageously cause the PCM 130 to undergo a phase transition from its first solid phase to its second liquid phase, allowing the heating panel 100 and its surroundings to be subsequently heated by triggering the PCM 130 to reverse this phase transition using the ultrasonic transducers 160, and leaving the heating films 140 inactive.

Figure 2 shows a thermal mass 200 for use in a heating panel according to the first aspect of the present invention. The thermal mass 200 being of a similar construction to the thermal mass comprised by the heating panel 100 shown in Figure 1.

The thermal mass 200 comprises a flat, relatively thin, cuboid central panel 220 which is intermediate two relatively thick side blocks 230 which extend along and cover the sides of the central panel 220. A network of interconnected conduits 225, 235 extend through the thermal mas 200 and in use hold a phase change material for a heating panel.

The central panel 220 comprises, three large, flat, thin, panel shaped, blocks of material 222, 224, 226 arranged face to face, parallel to one another and orthogonal to the thickness of the thermal mass 200. The central block 200 further comprises two smaller edge blocks 228 which cover width wise edges of the panels 222, 224, 226 which extend between the side blocks. The arrangement of the blocks 222, 224, 226, 228 is shown in Figure 3.

The three parallel blocks 222, 224, 226, are an upper block 222, a central block 224, and a lower block 226. The three blocks 222, 224, 226 are substantially cuboid and have the same length, width and depth.

A plurality of width-wise extending parallel grooves are formed in the lower face of the upper block 222, on the upper and lower faces of the central block 224, and on the upper face of the lower block 226. The grooves 225 having separations greater than their thickness and are interspaced such that the elongate openings of each groove 225 are covered by an un-grooved portion of another adjacent block. As such the grooves 225 are enclosed along their lengths such that they define conduits from one side of the central panel 220 to the other. The conduits 225 being arranged in four layers.

The side blocks 230 are substantially cuboid and have a square cross section in the plane orthogonal to the length for the of the thermal mass 200. The side blocks 230 are substantially thicker than the central panel 220, and comprise substantially hollow interiors 235. Each side block 230 comprises a single elongate slot 234 with length and thickness equal to that of the central panel 220 which provides access to the hollow interior 235 of the side block. The sides of the central panel 220 are received by the grooves such that the ends of the conduits 225 open into the hollow interiors 235 of the side blocks 230. As such the hollow interiors 235 of the side blocks define length wise extending conduits which interconnect the width wise extending conduits 225 comprised by the central panel 220. The interconnected conduits 225, 235 define a ladder shaped network of conduits for receiving a phase change material in use.

Each side block comprises a valve 236 at one end which provides access to the hollow interior 235 of the side block. In use a PCM may enter or exit the thermal mass 200 through the valves when they are open.

Referring to figure 6 there is shown a second heating panel 300 according to the first aspect of the present invention. The heating panel 300 having a different construction to the heating panel show in figure 1. The heating panel 300 comprises a thermal mass 320, a layer of electric heating film 340, and two networks of conduits 360 embedded within the thermal mass 320.

The thermal mass 320 is a flat cuboid shaped panel of plaster of Paris, and is shown in Figure 10. The thermal mass comprises two interwoven comb-shaped networks of plastic piping 360 each of which contain a phase change material. Figures 7 to 9 show the process of manufacturing the thermal mass 320.

The thermal mass may be cast from plaster of Paris.

Figure 7 shows a mould 380 for casting the thermal mass 320 from plaster of Paris. The mould 380 comprises a first plate 382, and four removable edge portions 384 which are connected to the first plate 382 by nuts and bolts such that they define a cuboid shaped cavity 386 therebetween, in which the thermal mass 320 is cast.

Figure 8 shows the mould 380 with a first network of conduits 360 located within the cavity 386. The network of conduits 360 comprises seven parallel length wise extending tubular pipes, which are sealed at their first ends and connected to a single width-wise extending tubular pipe at their second ends., so as to define a comb shaped network of piping 360 The tubular pipes 360 contain a phase change material, which is in thermal contact with the surrounding thermal mass 320.

Three supports 362 extend width wise across the cavity 386 and are spaced along the length of the length wise extending conduits so as to maintain the spacing and parallel arrangement of the conduits along the length of the cavity 386. The supports 362 comprise rigid strips of material in a plane perpendicular to the length of the heating panel 300, each with fifteen regularly spaced circular apertures formed therethrough.

A second network of interconnected conduits 360 is arranged in the cavity 386 before the plaster or Paris is poured into the cavity 386. The second network of conduits 360 comprises eight parallel length wise extending tubes, which of which are sealed at one end and connected to a single width wise extending tube at the other end, so as to define a second comb-shaped network of conduits 360 which interdigitates with the first network 360. The second network of conduits 360 also contains a phase change material. The length wise extending tubes of the second network of conduits are also received, supported, spaced apart, and maintained parallel by the three supports 362.

After the conduits 360 and supports 362 are arranged within the cavity 382, the cavity 382 is filled with liquid plaster of Paris which subsequently sets to form the thermal mass 320 with the conduits 360 embedded therein. The edge panels 384 may then be removed to facilitate the removal of the thermal mass 320.

Figure 9 shows the partially disassembled mould 380 containing a set thermal mass 320 with first and second networks of conduits 360 embedded therein. Three of the four edge portions 384 have been removed to facilitate removal of the thermal mass 320.

Figure 10 shows the cuboid thermal mass 320 after it has been removed from the mould 380, and Figure 6 shows the thermal mass 320 with a layer of 240V DC electric heating film 340 covering one of the large faces of the cuboid thermal mass 320, so as to define a complete thermal panel according to the first aspect of the invention.

The heating panel may optionally comprise additional features, such as an enclosing casing, or a PCM phase transition triggering means. In some embodiments the panel may be located within a cavity of an item of furniture, such as the doors shown in Figures 11 to 18.

Figures 11 to 13 show a door first door 400 according to the second aspect of the present invention which comprises a heating panel 440 according to the first aspect of the invention.

The door 400 is substantially cuboid, and is formed of three parallel substantially cuboid panels 405, 410 stacked face to face and two side panels 415 which cover the vertical side edges of the three interconnected parallel panels 405, 410. The three parallel panels are two substantially planar outer face panels 405 which define the two faces of the door 400, and a thicker intermediate panel 410.

An elongate vertical rectangular window 420 is formed through all three parallel panels 405, 410 of the door; the window is parallel and proximate to a first vertical side edge of the door 400.

Intermediate the window 420 and the second vertical side edge of the door 400, an aperture is formed through the width of the intermediate panel 410 of the door 400. The aperture defines a cuboid cavity 430 between the two face panels 405 of the door 400. Figure 13 shows the door 400 with one of the face panels 405 removed and the cavity 430 empty and accessible.

Located within the cavity 430 is a heating panel 440 according to the first aspect of the invention, for example a heating panel 300 as illustrated in Figure 6. Figure 12 shows the door 400 with one of the face panels 405 removed and the cavity 430 accessible and filled with the heating panel 440.

The heating panel 440 is substantially cuboid, and fills the majority of the volume of the cavity 430 and has an electric heating film formed over one large rectangular exterior face of the heating panel, between the thermal mass and one of the outer faces 405 of the door.

An electrical connection extends from the heating panel 440 through a width-wise aperture in the intermediate panel 410 and one of the side panels 415 of the door 400, out of the side of the door 400. This connection extends out of the door and into the door frame and provides power the electrical components of the heating panel 440 in use.

In use, the electric heating film comprised by the heating panel 440 may be activated (for example, by a central heating system, or manually by a user) to heat the door 400 and the environment within which the door 400 is located. This also heats the phase change material contained within conduits extending through the thermal mass of the heating panel, causing it to undergo a phase transition, thereby storing a large amount of thermal energy for subsequent release.

The door 400 further comprises four vertically extending grooves 450 formed in the surface of the intermediate panel 410, which extend through the cavity 430. The grooves 450 are enclosed by one of the face panels 405 such that they define conduits from the base of the door 400 into the cavity, and from the cavity 430 to the top of the door 400. In use air may enter the cavity 430 via these conduits from the base of the door 400, may then be heated by the heating panel and may subsequently exit out of the top of the door 400 via the conduits 450. This may establish a convection current for heating the air of the environment within which the door is located.

Figures 14 to 18 show a second door 500 according to the second aspect of the present invention, which also comprises a heating panel according to the first aspect of the present invention.

As with the door 400 shown in Figures 11 to 13, door 500 is substantially cuboid, and is formed of three parallel substantially cuboid panels 505, 510 stacked face to face, and two side edge panels 515. The three parallel panels are two substantially planar outer face panels 505 which define the two faces of the door 500, and a thicker intermediate panel 510.

An elongate vertical rectangular window 520 is formed through all three parallel panels 505, 510 of the door, the window is parallel and proximate to a first vertical side edge of the door 500.

A horizontal rectangular aperture 525 is formed through all three parallel panels 505, 510 of the door, the aperture is parallel and proximate to the upper horizontal edge of the door 500. When the door 500 is fully assembled the horizontal rectangular aperture 525 receives a control and power unit 580.

Figure 14 shows the intermediate panel 510 of the door 500 and a single outer face panel 505. In figure 6 the intermediate panel 510 has been flipped about its horizontal axis with respect to the outer face panel 505, such that while the horizontally symmetric openings for the horizontal rectangular apertures 525 are aligned with one another, the opening for the window 520 formed through the outer face panel 505 is aligned with a cavity 530 of the intermediate panel 510, rather than with the opening for the window 520 formed through the intermediate panel 510. Similarly, the opening for the window 520 formed through the intermediate panel 510 is aligned with the portion of the face panel 505 which would normally cover the cavity 530.

Intermediate the window 520 and the second vertical side edge of the door 500, and intermediate the horizontal rectangular aperture 525 and the lower horizontal edge of the door 500, an aperture is formed through the width of the intermediate panel 510 of the door. The aperture defines the cuboid cavity 530 which is bounded on four sides by the intermediate panel 510, and on two opposite sides by the two face panels 505 of the door 500. In use the cavity 530 receives a thermal mass 540, for example, the thermal mass 300 shown in Figure 6.

Four concentric rounded rectangle-shaped grooves 570 are formed in the inner face of one of the outer face panels 505. The grooves 570 being arranged such that they surround the window 520. The rounded rectangle shaped grooves 570 each have first and second substantially vertical lengths connected by upper and lower substantially horizontal lengths, the substantially vertical and substantially horizontal lengths being connected by rounded corners.

The rounded rectangle shaped grooves 570 are each arranged with a first substantially vertical length, two rounded corners, and portions of the upper and lower substantially horizontal lengths being formed in the portion of the inner face of the outer face panel 505 that defines a surface of the cavity 530. The second vertical lengths of the grooves 570 being formed on the far side of the window 520 from the cavity 530.

The arrangement of the grooves 570 is shown in Figures 14 and 17.

Additional grooves, such as LED connection groove 595, for electrical conduits and components are formed in the surface of the intermediate layer 510 of the door 500, as shown in Figures 14 and 15.

Figure 15 shows the intermediate panel 510 of the door 500, with a thermal mass 540 which comprises a 240V DC electric heating film located within the cavity 530.

Figure 16 is a diagram showing the arrangement of the electrical components of the door 500, including the control and power unit 580 and the 240V DC electric heating film 560.

In the illustrated embodiment, the electrical control and power unit 580 comprises an electrical input 581, a power switch 582, a voice control unit 583, an electrical relay 584, a component 585, two USB Hubs 586, a fan unit 587, a USB power-bank 588, and an RF switch 589.

Component 585 may be connected to a current transformer or transducer on the input power line.

The electrical input 581 is an electrical connection which extends from the upper horizontal aperture 525 through the intermediate panel 510 and the side panel 515, to the side of the door 500. There it comprises an electrical connector; such as a C8 socket for connection to an external power source. In some embodiments, a flexible electrical connector may connect the electrical input 581 to an electrical connection in the door frame at all times, in other embodiments the electrical input 581 may only be connected when the door 500 is closed.

The power switch 582 selectively allows passage of, or blocks electrical power form the electrical input reaching the three-way relay. The switch 582 may be accessible on the exterior face of the door such that it may be manually actuated by a user, and/or may be a smart switch which may be actuated wirelessly, for example by a remote control, a smartphone app, or by a smart thermostat.

The electrical relay 584 selectively powers two electrical outputs which provide power to two electrical circuits. In the illustrated embodiment, the electrical relay 583 is a three-way relay, two of whose outputs are connected to the two circuits. The first circuit comprises the first USB hub 586 and the fan unit 587 (the first output powers the first USB hub 586 provides power to each individual fan comprised by the fan unit 587). The second circuit comprises the second USB hub 586, the component 585, the USB power-bank 588, the RF switch 589, and LED 590 and the electrical heating film 560.

In the illustrated embodiment, the voice control unit 583 is an Amazon Echo (RTM) smart speaker embedded within the electrical control and power unit running the Amazon Alexa (RTM) intelligent personal assistant. The voice control unit may be used to control the heating of the door 500, in addition to other functions such as the fans 587.

The electrical relay 584s second output provides power to the second USB hub 586, and when the RF switch 589 is activated, to the electrical heating film 560. The second USB hub provides power to the USB power-bank 588 and the component 585. The USB power-bank 588 provides power to the voice control unit 583 and the LED 590.

The RF switch 589 is controlled remotely by a RF thermostat. The switch may also be manually actuatable.

The LED 590 is located below the window 520 and is connected by an electrical connection which extends along a groove 595 formed in the outer surface of the intermediate panel 510 of the door 500. The LED extends through one of the outer face panels of the door 505 and may show when the circuit comprising the electrical heating film is powered.

Figure 17 shows vertical and horizontal cross sections of a fully assembled door 500 located within a door frame, showing the arrangement of the panels 505, 510, 515 the window 520, the heating panel 540, the rounded rectangular tubes 570, the power and control unit 580 and the LED 590.

Figure 18 is an overall external view of the fully assembled door 500 open when supported by a door frame, showing the external view of the power and control unit 580.

Figure 19 shows a sitting desk 610 and a standing desk 620, both comprising a heating panel according to the first aspect of the present invention so as to provide heat to users 640 at the desk.

Figure 20 shows a room containing sitting and standing desks 610, 620 comprising heating panels according to the present invention and a door 500 comprising a heating panel according to the present invention. The desks 610, 620 and the door provide heating which is effectively localised around the users 640 at the desks.

Figure 21 shows a room heated by a convention radiator 630 leading to heat concentrating around the ceiling.

Figure 22 shows a building, one wing of which is heated using conventional radiators 630 and one wing of which is heated using desks 610 comprising heating panels according to the present invention.

The invention has been described by way of example only and it will be appreciated that variation may be made to the embodiment described above without departing from the scope of the invention as defined by the claims.

Claims

Claims 1. A heating panel comprising: a thermal mass, one or more conduits for containing a phase change material which extend through the thermal mass, and an electric heating element for heating the thermal mass and the phase change material within the conduits.
2. A heating panel according to claim 'I comprising a casing within which the thermal mass, the conduits and the electric heating element are located.
3. A heating panel according to claim 1 or claim 2 wherein the thermal mass is formed from soapstone.
4. A heating panel according to claim 1 or claim 2 wherein the thermal mass is formed from plaster of Paris.
5. A heating panel according to any preceding claim wherein the one or more conduits are elongate holes formed through the thermal mass.
6. A heating panel according to any of claims 1 to 4 wherein the one or more conduits are pipes embedded within the thermal mass.
7. A heating panel according to any preceding claim comprising a plurality of conduits for containing a phase change material which extend through the thermal mass.
8. A heating panel according to claim 7 wherein two or more of the plurality of conduits are interconnected to form a network of conduits.
9. A heating panel according to any preceding claim wherein the thermal mass comprises a plurality of interconnected blocks of material and at least one of the one or more conduits is defined by a groove formed in the surface of one of the plurality of the block of material which is at least partially enclosed by another of the plurality of the blocks of material.
10.A heating panel according to any preceding claim comprising a phase change material within the one or more conduits.
11.A heating panel according to claim 10 wherein the phase change material transitions from a first phase to a second metastable phase when heated to or above a transition temperature.
12.A heating panel according to claim 10 or claim 11 wherein the phase change material is an organic phase change material.
13.A heating panel according to any preceding claim comprising one or more triggering means for triggering a phase change material to transition from one phase to another phase.
14.A heating panel according to claim 13 wherein the triggering means is an ultrasonic transducer.
15.A heating panel according to any preceding claim wherein the electric heating element is embedded within the thermal mass.
16.A heating panel according to any preceding claim wherein the electric heating element is an electric heating film.
17.A heating panel according to claim 16 wherein the electric heating element is formed on the surface of the thermal mass.
18.A heating panel according to any preceding claim wherein the thermal mass is formed from a fire-retardant material.
19. An item of furniture comprising a cavity, and a heating panel according to any preceding claim which is located within the cavity.
20.An item of furniture according to claim 19 comprising an electrical input connection.
21.An item of furniture according to claim 19 or claim 20 comprising a battery.
22. An item of furniture according to any of claims 19 to 21 wherein the item of furniture is a door, a table, or a desk.
23. An item of furniture according to any of claims 19 to 22 wherein the heating panel substantially fills the cavity.
24. An item of furniture comprising a control unit for controlling the heating panel.
25. An item of furniture according to any preceding claim wherein an external control system controls the heating panel.