GB2482650A

GB2482650A - Exterior cladding panels with climate control

Info

Publication number: GB2482650A
Application number: GB1003809.9A
Authority: GB
Inventors: Samuel Gerard Bailey
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-03-08
Filing date: 2010-03-08
Publication date: 2012-02-15
Anticipated expiration: 2030-03-08
Also published as: GB201003809D0; GB2482650B

Abstract

A panel comprising an insulation layer 4, a solar absorber plate 5 which can have a glazed covering 6. The panel further comprises a heat exchanger panel 3 with conduits 2 which are connected via a fluid circuit to the solar absorption panels. The panel may form part of a climate control system for a building consisting of a combination of a radiant heating or cooling system to best maintain a desired temperature within the building. The system may include solar collection panels 10 and radiant cooling plates 12. There may be an additional heat exchanger unit in the ground and there may be an ECU (electronic control unit) to maintain the ambient temperature within the building.

Description

EXTERIOR CLADDING PANELS WITH CLIMATE CONTROL

This invention relates to a controllable insulated cladding system.

Many existing buildings have solid brick walls or uninsulated cavity walls. These have poor thermal insulation properties, as the thermal conductivity of brick is relatively high. A 9" solid brick walls has a thermal conductivity (U value) of around 2.2 WK1m2. Much of the existing housing stock in the UK is of such construction.

Many of these houses are or will be retrofitted with improved loft insulation and double glazing. However this will leave heat conductivity through the walls as the major source of heat loss, and often the major contributor to the energy consumption of the household. Options for improving insulation of the walls is limited. Walls may be dry lined' by adding a layer of foam or polystyrene or other insulator on the inside and overlaying it with plasterboard. However this incurs considerable disruption to the householder and reduces the available space in the building. Exterior cladding is also available. Typically this is a layer of insulating foam, faced with a weatherproof cladding on which brick slips are mounted. This has the advantage that the thermal mass of the fabric of the building is on the insulated side, and reduces temperature fluctuations within the building due to heat loss and solar gain. However during sunny winter days much solar energy gain is wasted due to the additional insulation and poor absorption properties of the exterior. Also during summer, the building may overheat due to a reduced capacity to reject unwanted heat.

This invention relates to a climate control system, built into exterior cladding panels which are used to insulate an existing brick, stone or concrete building. It is suited primarily to temperate climes. It exploits the solar thermal gain on the exterior of the building, the nighttime heating loss and the thermal mass of the existing fabric of the building to maintain a stable internal temperature within the building with minimal external energy input.

Systems have been patented, though are not generally commercially available which perform a similar function on a metal clad building (e.g. GB1413675 A), but do not make use of existing thermal mass, thus requiring either the addition of thermal mass, or may perform sub optimally at maintaining constant temperature over the diurnal cycle. Additionally they may require phase change working fluids that evaporate and condense during the thermal cycle, which are costly and difficult to handle as they will typically need to be maintained at sub atmospheric pressure to function.

The target building comprises a pre-existing brick, concrete or other structure of substantial thermal mass as shown in Fig 1. In this invention, the building walls are clad with modified insulated panel type cladding. In immediate thermal contact with the existing wall (1) is a heat exchanger panel (3) with conduits in it (2) to allow a working fluid to pass through. There is a then a layer of insulation (4), which would typically be thicker than the standard exterior insulation used in such a building. The cladding then has an external skin which varies in composition according to the orientation relative to the sun. South facing walls in the Northern hemisphere face the sun (11) and are clad with a suitable solar absorber plate (5) with conduits for working fluid, and glazed with a suitable material (6) to allow incident radiation through, but minimise heat loss out, constructed in a manner similar to solar thermal collectors of design known in the art. North facing exterior layers have no specific absorption characteristics, and may be chosen to match a desired style e.g. brick slips (9). They have heat exchanger plates behind them (8), with fluid conduits (7) in thermal contact with the back of the exterior layer. These act as cooling panels when a fluid is passed through conduits behind them and the external temperature is low (e.g. at night). Each section of cladding has inlet and outlet pipes for the internal and external heat exchangers so that they can be connected together to form a circuit. In conjunction with the existing interior walls, the heat exchanger panels form a radiant heating and cooling panel.

In a possible embodiment, the roof of the building may also have a series of solar panels as shown. The solar collection panels (10) are orientated to face the sun (11) (South in the Northern Hemisphere, North in Southern) and inclined to maximise solar gain during the winter. The radiant cooling plates (12) are inclined to face away from the sun and to minimise occlusion of the sun on the solar panels, and to minimise the view factor between them and the solar heating panels or other nearby buildings. The solar collection panels are of a standard design known in the industry, e.g. flat panel or evacuated tubes. The radiant cooling plates are typically of a similar design to the solar collectors, but may have reduced insulation properties.

In another possible embodiment, as shown in Fig 2, the roof mounted solar panel (1) can be elevated by mechanical means of a pivot (3) and an actuator (4) when required, and can sit flush against the roof (2) when not in use.

In a further embodiment as shown in Fig 3, the roof mounted panels may be stepped in design (1), such that they can achieve an elevation angle as required, without protruding excessively from the roof (2).

Two circuits are formed between the sets of pipes (between internal and external heating and internal and external cooling) and are connected to form separate circuits, each with a pump (or a single pump and controllable valves), and each with a heat exchanger in contact with the other circuit. There may also be a regular (e.g. gas fired) heater in the interior circuit, which provides back up heat for very cold and extended overcast periods.

There may also be an additional heat exchanger circuit consisting of a pipe buried in the ground to provide good thermal contact with the ground (typical of those used for ground source heat pumps), connected via a heat exchanger to the thermal store and with a circulation pump. This circuit may be activated to pump heat from the thermal store into the ground to provide additional cooling. In another embodiment, it may be used in place of the roof mounted cooling panels.

In another embodiment, an additional thermal store may be placed in the circuit to supplement the thermal mass of the fabric of the building.

The tank or pipes are filled with a working fluid, for example either water or an anti freeze mix e.g. glycol.

An electronic control unit (ECU) has sensors which take a series of temperature inputs measuring the temperature of the air within the building, the water in the exterior solar panel, the water in the cooling panels and the brickwork acting as the thermal store. It typically also has sensors which measure the humidity. The ECU controls the pumps and valves and has a software control algorithm in it.

In order to still function in the case of a shortage of energy, such as electricity, the system may additionally have a layout such that the working fluid rises upwards due to convection in the solar panels, and downwards in the heat exchanger in the interior of the panels. This will allow the system to exchange heat between the solar panels and the fabric of the building in case of a power outage.

To minimise the amount of internal space in the building required to accommodate the system, the system may have a control cabinet mounted on the outside of the building into which the conduits run, as in Fig 4. This can then contain the pumps (5), valves (4), manifolds (3), expansion vessels and controls for the system without the need to locate them inside the building. The cabinet (1) may be designed such that it fits within the profile of the exterior cladding (2) to reduce the space required to accommodate the system, and have an insulated door (6) for access and to protect the system from frost.

A typical action of the system is as follows Winter cycle: Heat input required to the building 1) If the temperature inside the building is less than the desired set point, and/or the temperature of the brickwork forming the main fabric of the building is below the desired set point and the temperature of the outer solar collectors is higher than the set point, the circulation pump between the exterior heating and thermal store panels is activated. This pumps heat from the exterior panels directly into the building.

2) Otherwise the pump is deactivated to minimise heat transfer between the interior panels and the outside of the building.

3) If the temperature inside the building is less than the desired set point, and the temperature of the outer skin is below the set point, the circulation pump between the interior heating panels and the back up heat source (e.g. gas boiler), if fitted, may be activated, along with the back up heat source. This heats the building using the back up heat source.

Summer cycle: Cooling required to the building.

1) The temperature of the cooling panels is monitored. Typically during the day it will exceed the set point temperature and no heat exchange will take place, except through the building insulation and air exchange. At night the temperature of the exterior cooling panels will usually drop below the temperature of the fabric of the building, due to radiation into the night sky and low air temperature. If the temperature of the fabric of the building is above the set point, the circulation pump between the cooling panel and the thermal store is activated. This pumps heat from the building into the night sky, and cools the thermal mass of the building.

2) Alternatively, if a heat exchanger circuit in contact with the ground is present, it may be activated when the internal temperature of the building exceeds the set point, and the temperature of the water in the underground pipes is below the set point, to provide additional cooling.

An alternative embodiment may also check for potential condensation. The humidity of the incoming air and inside air is monitored. If the incoming air is likely to reach its dew point when contacting interior walls of the building, forming condensation, then water from the radiant system is pumped into a liquid/air heat exchanger in the ventilation system. This will cause the moisture in the incoming air to condense in the heat exchanger, from where it can be drained, rather than on the walls and floors of the house.

Claims

CLAIMS1. A panel for fixing to the exterior of building which can control the rate of solar heat absorption, insulation and heat conduction into and out of the building by means of having a series of conduits in thermal contact with the exterior of the building, connected via a fluid circuit to solar thermal absorption panels on the exterior surface of the building, and an insulation layer which can isolate the rate of heat transfer between the outside air, and/or the solar panels, and the main fabric of the building when the working fluid is not flowing.
2. A system as in 1, where the rate of flow of the working fluid can be controlled by circulation pumps and/or valves.
3. A system as in 1 and 2 where the control of the circulation pumps and/or valves is determined by an electronic control system which measures the temperature in and or of the building, and the temperature of the fluid in the solar panels and controls the fluid flow in the circuit to attempt to maintain a desired set point temperature in the building.
4. A system as in 1, where cooling is provided by circulating the working fluid through conduits on the exterior surface of the building when the exterior panels are at a temperature lower than the desired set point temperature, and the building is above the desired temperature.
5. A system as in 1, where the cooling is provided by circulating the working fluid through conduits embedded in the ground or a water source.
6. A system as in 1, where the fluid circuit is arranged such that the fluid in the heat source (the warmer solar panels) rises due to convection, then falls again when in contact with the heat sink (the exterior surface of the building) such that a convective flow is established without the need for additional circulation pumping.
7. A system as in 1 and 6 where the convection flow can be turned on or off by means of a bypass valve.
8. A system as in 1, 6 and 7 where the bypass can be overridden by the control system to prevent overheating of the building.
9. A system as in 1 with an integrated control cabinet, into which the fluid conduits are routed is mounted on the exterior of the building.
10. A system as in 1 and 9 where the contents of said control cabinet comprise the pipes, valves and circulation pumps necessary to control the working fluid flow rate according to a given control logic.
11. A system as in 1 and 9 where the cabinet is set into the insulation panels on the outside of the building to minimise the obtrusion on the outside of the building.
12. A system as in 1 and 9, where the control cabinet is thermally insulated to protect the control equipment from temperature extremes.
13. A system as in 1, where an additional air ventilation system with heat exchanger is provided which can utilise the temperature of either the thermal store, the roof mounted cooling or underground cooling source to reduce humidity inside the building.
14. A system as in 1, where additional roof mounted solar thermal collectors are connected to the working fluid circuit to provide extra solar energy to the system.
15. A system as in 1 where additional radiant heating and/or cooling panels are fitted in the building and connected to the working fluid circuit.
16. A system as in 1 where said conduit is a pipe in labyrinthine layout.
17. A system as in 1 and 16 where heat spreader plates provide additional heat exchange.
18. A system as in 1 where said conduits are preformed radiator panels.
19. A system as in 1 and 14, where the roof mounted solar thermal collectors can be mechanically elevated such that they face the sun when required, and sit flush on the roof when not in use.
20. A system as in 1 and 14, where the roof mounted solar thermal collectors are of a stepped design, such that they face the sun under optimal conditions, but do not protrude excessively above the roofAMENDMENTS TO THE CLAIMS HAVE BEEN FILED AS FOLLOWS1. A climate control system which can control the rate of solar heat absorption, insulation and heat conduction into and out of a brick, concrete or stone building, said system comprising: a) a panel for fixing to the exterior of said building, said panel having a series of internal conduits for working fluid arranged to be in thermal contact with the exterior of the building, heat spreader plates to provide additional heat exchange and an insulation layer which can isolate the rate of heat transfer between the outside air, and/or the solar panels, and the main fabric of the building when the working fluid is not flowing, b) glazed solar thermal absorption panels for fixing to the exterior surface of the building, and C) an electronic control system which measures the temperature in and/or of the building, and the temperature of the fluid in the solar panels and controls the fluid flow in the circuit, wherein the series of conduits in said panel is connected via a fluid circuit to said glazed solar thermal absorption panel.2. The climate control system of claim 1 wherein said glazed solar thermal panels form an exterior skin on said panel.3. The climate control system of claim 2 wherein said panel is suitable for fixing to a south facing wall in the northern hemisphere.4. The climate control system of any one of claims 1 to 3 further comprising a cooling panel suitable for fixing to a north facing wall in the northern hemisphere, said panel comprising an internal heat exchanger panel with conduits in it to allow a working fluid to pass through, said heat exchanger panel being configured to be in immediate thermal contact with the wall of said building, a layer of insulation, and external fluid conduits in thermal contact with the back of the exterior layer of the panel, wherein a circuit is formed between the internal conduits of the climate control system and the external fluid conduits of said cooling panel and a circuit is formed between the internal conduits of the climate control system and the glazed solarthermal absorption panels and external conduits. ...5. The climate control system of any one of claims 1 to 4, wherein the rate of flow of the working fluid in said conduits is controlled by circulation pumps and/or valves.6. The climate control system of any one of claims 1 to 5, wherein cooling is provided by circulating the working fluid through said fluid conduits on the internal surface of the building and the fluid conduits of the external panels, when the external panels are at a temperature lower than the building temperature, and the building is above the desired setpoint temperature.7. The climate control system of any one of claims I to 5, wherein cooling is provided by circulating the working fluid in said conduits through further conduits embedded in the ground or a water source.8. The climate control system of any one of claims 1 to 7, where the fluid circuit is arranged such that the fluid in the heat source rises due to convection, then falls again when in contact with the heat sink such that a convective flow is established without the need for additional circulation pumping.9. The climate control system of claim 8 wherein the convection flow can be turned on or off by means of a bypass valve.10. The climate control system of claim 9 wherein the bypass can be overridden by the control system to prevent overheating of the building.11. The climate control system of any one of claims 1 to 10 with an integrated control cabinet, into which the fluid conduits are routed, for mounting on the exterior of the building.12. The climate control system of claim 11 wherein said control cabinet comprises the pipes, valves and circulation pumps necessary to control the working fluid flow rate in said conduits according to a given control logic.13. The climate control system of claim 11 or 12, wherein the cabinet is set into the insulation panels on the outside of the building to minimise the obtrusion on the outside of the building.14. The climate control system of any one of claims 11 to 13, where the control cabinet is thermally insulated to protect the control equipment from temperature extremes.15. The climate control system of any one of claims I to 14, wherein an additional air ventilation system with heat exchanger is provided which can utilise the temperature of either the wall of the building, the roof mounted cooling or underground cooling source to reduce humidity inside the building.16. The climate control system of any one of claims I to 15, further comprising solar thermal collectors for roof mounting, connected to the working fluid circuit to provide solar energy to the system 17. The climate control system of any preceding claim further comprising additional radiant heating and/or cooling panels for fitting in the building which are connected to the working fluid circuit.18. The climate control system of any preceding claim wherein said conduits are S... preformed radiatorpanels.19. The climate control system of claim 16 wherein the solar thermal collectors for roof * mounting can be mechanically elevated such that they face the sun when required, and ". d: sit flush on the roof when not in use.20. The climate control system of claim 16 wherein, where solar thermal collectors for roof mounting are of a stepped design, such that they face the sun under optimal conditions, but do not protrude excessively above the roof.
21. A building fitted with the climate control system of any one of claims I to 20.