GB2273151A - "Solar energy transfer structual elements." - Google Patents

Abstract

Solar energy transfer structural elements, in the form of wall or window units 10 are part of a heat regulation system having heat exchangers 20, 22 disposed respectively internally and externally of a building. Thermostatically controlled means 19, 21 control flow of coolant fluid from a unit 10 so that it passes through either exchanger 20 or 22 dependant whether it is desired to heat the interior or prevent it being heated by solar radiation absorbed by the coolant. <IMAGE>

Description

SOLAR ENERGY TRANSFER STRUCTURAL E:EEMENTS SND ARRANGEMENIIS THEREOF This invention relates to solar energy transfer structural elements and arrangements thereof. By a "solar energy transfer structural element" is meant a transparent or translucent window or a wall or roof cladding or curtain walling component arranged to receive incident sunlight.

whether or not the element is adapted to admit at least some of such light to the building of which the element forms a part, its principal purpose is to transfer heat to or from a fluid passing through the element.

Eurapean Patent No. 0075464 describes and illustrates such a structural element in the form of a window and reference is made thereto for a fuller understanding of the present invention. Specifically, European Patent No. 0075464 describes a window structure comprising a plurality of parallel channels of a transparent or translucent material through which a liquid, which is preferably darkened or otherwise treated to improve its energy absorption characteristics, is passed between headers at the top and bottom of the window. In so doing the liquid absorbs heat fran the incident sunlight which can thereafter either be dissipated or used to heat the interior of the building.

Figure 1 of the accompanying drawings illustrates such a structural element suitable as a wall or roof cladding or curtain walling component.

The element 10, of glass or a suitable plastics material, comprises a plurality of parallel, vertical channels or ducts (not shown) extending between headers 11 and 12 at the top and bottan of the window. These headers are connected to respective tubes 13 and 14 whereby a liquid such as water can be caused to flaw through the channels of the element, thereby either absorbing or dissipating heat energy. A pane 17 of clear glass is positioned in front of the element 10 and between them is a space 18 which may contain air or a suitable gas. The pane 17 is on the side of the element 10 which will be exposed to incident sunlight, in use, and its function and that of the air/gas space 18 is to promote heat and noise insulation according to the well-known principles of double-glazing.At the same time the pane 17 may, if desired, subject the element 10 to the wall-known "greenhouse" effect of energy conservation by impeding the escape of radiant heat.

In accordance with this emlxxirment of the present invention there is positioned behind the element 10 (i.e. on the side which will be presented to the interior of the building in which the element is incorporated) a layer 14 of a light-reflective material, and on the opposite side of the layer 14 a layer 15 of a heat insulative material such as a foamed plastics material or rock wool. The layer 14 will reflect unabsorbed light and heat of sunlight which has already passed through the element 10 back through the element 10 so that residual heat can be absorbed by the liquid passing through the channels of the element 10. The layer 15 will absorb any heat which passes through the reflective layer 14 to prevent its penetration into the building and radiate it back to the element 10 for absorption by the liquid.

It will be appreciated that the layers 14 and 15 will impair visibility through the windaw 10. Howaver this will not matter if the element is one of a number incorporated in the building, or if it does not serve for visibility at all but solely as a wall or roof cladding panel.

The layers 14 and 15 may be mounted jointly with the element 10 and the glass pane 17 in the same frame 16 surrounding the assembly on four sides and with the tubes 13 and 14 extending from the frame for connection by suitable couplings (not shown) to other pipework. In this way units such as illustrated in Figure 1 may be prefabricated for installation in apertures of standard sizes provided in buildings during construction.

The liquid circulated through the channels of the unit 10 may contain pthalocyanine dye substances dissolved in water and inhibitors such as antifreeze and anti-fungal additives.

Figures 2 and 2A of the acecwpanying drawings illustrate a window 10 having generally the same structure as the element of Figure 1 but with the layers 14 and 15 omitted. In this ewtodisent of a window the tubes 13 and 14 are included in a fluid circuit which also includes a thermostat 19 and a heat exchanger 20 positioned inside the building in which the window is incorporated and there are also connected to the headers of the window 10 additional tubes 13A and 14A included in a second fluid circuit which also includes a second thermostat 21 and a second heat exchanger 22 positioned outside the building in which the window 10 is incorporated.The external heat exchanger is protected fran incident sunlight such as by the provision of a shade 23 fixed to the building.

The thermostats 19 and 21 function selectively to circulate the fluid passing through window 10 either to the heat exchanger 20 or to the heat exchanger 22 according to prevailing conditions or requirements. If the window 10 is subject to excess solar heat which is not wanted within the building the fluid is circulated to heat exchanger 22, which dissipates the excess heat to ambience outside the building. Alternatively if the interior of the building falls below a temperature pre-set by the thermostat 19 which is also lower than the temperature of the fluid the thermostat 19 apens and thermostat 21 closes so that fluid fran window 10 is circulated through internal heat exchanger 20.In yet another variant, if the temperature in the interior of the building is above a value preset by the thermostat 19 which is also higher than the temperature of the fluid the thermostat 21 is opened and flaw of fluid through external heat exchanger 22 will cool the interior of the building.

The thermostats 19 and 20 may be interconnected such that when one opens the other closes. Manual over-ride means (not shown) may be provided. If thermosyphon is insufficient for circulation of the fluid one or more pumps may be used, and either of the heat exchangers may have an associated air fan to promote heat exchange. Any or all of the pipes 13, 14, 13A, 14A may include vertical channels hidden within the frame of the window.

Figure 3 of the accompanying drawing illustrates a plurality of interconnected windows or wall or roof cladding or curtain walling panels 10 which each may be as described in relation to Figure 1 or Figures 2 and 2A.

The windows or panels 10 are in four groups 24, 25, 26 and 27 on the four sides of a building, each group comprising a plurality of arrays 28/29, 30/31, 32/33 and 34/35 of windows 10, each array of a given group being on a different floor of the building. It will be appreciated that the number and arrangement of groups and of arrays will be determined by the shape and by the height of the building. For purposes of illustration the arrangement of Figure 3 is for a four-sided building of which the side incorporating group 24 faces North.

As shown each of the individual arrays is included in a respective fluid circuit identified at A which also includes a respective heat exchanger or reversible heat pump 37. The latter is included in a separate fluid circuit B, isolated from the circuits A, which also includes a main heat exchanger or reversible heat pump 38 associated with each group 24 - 27.

At a convenient location in the building, such as in its basement, is a central storage tank or reservoir 36 for fluid, such as water, which is included in further fluid circuits C, isolated from the circuits B, which also include the main heat exchangers or reversible heat pumps 38. By this arrangement only the circuits A need to contain the relatively expensive fluid adapted to absorb heat fran sunlight, e.g. by the inclusion of a darkening agent.. Fluid in circuits B and C will not be exposed to sunlight and may be untreated water, or water treated in the same way as when used in a central heating system, e.g. with a rust inhibitor.

Further, the provision of separate, isolatd circuits A, B and C prevents the application of excessive mechanical loads on the components of the system.

This is important if the building is high so that the circuits B will be of great length and support long columns of water. Only heat is transferred between the circuits A and B and the circuits B and C by the heat exchangers or reversible heat pumps. There is no fluid comnunication across the latter.

The system of Figure 3 is under the control of thermal sensing means (not shown) at different locations around the building and/or on the windows or cladding elements 10 which selectively controls the circulation of fluid in the individual circuits A so that heat is transferred to or fran the circuits B in order to control the internal temperature of the building.

In the morning the group 25 and in the evening the group 26 of windows/cladding panels 10 will be subjected to greater incident sunlight than the remaining groups. Any excess heat of fluid in the circuits A of groups 25 or 26 can either be transferred to the circuits A of the ramaining groups via direct interconnections (not shown) between the circuits B to equalize temperature throughout the building or, if this is awl ready too high, heat from the circuits A of groups 25 or 26 can be transferred through the associated circuit C to the reservoir 36 for storage of the excess heat. When incident sunlight diminishes or is absent the stored heat can be utilised by transferring to the appropriate circuits A heat stored in the reservoir 36.If at any location in the building the temperature rises above a pre-set temperature the local units 10 act as heat exchangers to carry heat away via the associated circuits B to reservoir 36.

Artificial heat within the building, e.g. generated by lighting or by equipment, or the heat produced by people, is similarly re-distributed or stored.

In an alternative arrangement, (not shown), the building has two separate reservoirs such as 36, one for the storage of heated liquid and the other for the storage of low temperature liquid. The circuits C are duplicated and valve means is provided whereby high temEerature liquid is directed to one of the reservoirs and low temperature liquid to the other.

Liquid is drawn fran the appropriate reservoir to main heat exchanger 38 in response to a local demand for heating or cooling.

It is envisaged that the control of valves, thermostats and pump (if used) will be under the central control of a computer acting to maintain all parts of the building at pre-selected teperatures and to store any excess heat in the reservoir 36. The system may include coqpression, absorption or Peltier effect electric heat pumps, the latter two having no moving parts. Two or more buildings may share the same reservoir 36 so that any excess heat fran one building may be used to heat another. If heat has to be dissipated externally of a building, e.g. by the use of external heat exchangers, this will give rise to no pollution.

The piping connections of the individual circuits A, B and C may be in series or parallel.

In all of the aforedescribed embodiments of the present invention if fluid passing through a unit 10 is kept at or near the required internal temperature of the building any loss or gain of heat energy across the unit 10 will be fran or to the fluid - not to ambience or the building interior.

In the enlxxibmant of Figure 3 excess heat absorbed e.g. during the day is stored in reservoir 36 for use during the night. Alternatively in hot climates fluid stored during the night can be used to cool a building during the day.

By storing all available sources of heat gain or loss within the building for subsequent use or for use in another part of the building the eeeodent of Figure 3 provides an energy-efficient system which, with suitable development, may enable all sources of artificial heat to be dispensed with. The larger the units 10 the more efficient the system and it is therefore envisaged that at least the greater part of the wall, roof and/or floor areas of a building will be occupied by windows or cladding units 10.

Claims (3)

1. Iemperature regulation apparatus camrising at least one solar energy

transfer structural element in the form of an exterior wall or window unit, a coolant flow circuit connecting fluid channels within the unit to respectively first and second heat exchangers, biassing means switchable to direct fluid flow fran the unit to either the first or second heat exchanger, with said first heat exchanger being adapted to be fitted externally of a building to which the unit can be fitted, with the second heat exchanger being adapted to be fitted within the said building and with said biassing means being thstatically controlled valve nears having a manual override being adapted to be switchable dependent on the positive or negative temperature differential between the exterior and the interior of the building.

2. Apparatus in accordance with claim 1, in which the coolant flow circuit further connects said fluid channels to a reservoir in the form of a heat sink with the reservoir being adapted to be insulated fran the interior and exterior of the building.

3. Temperature regulation apparatus or a method of temperature regulation substantially as hereinbefore described and/or as illustrated in Figure 1 or Figure 2 of the drawings.