WO2010019055A1

WO2010019055A1 - A construction element

Info

Publication number: WO2010019055A1
Application number: PCT/NZ2009/000162
Authority: WO
Inventors: Larry Arthur Bellamy; Leonard George Mcsaveney; Christopher Paul Badger
Original assignee: Badger, Terry Christine
Priority date: 2008-08-12
Filing date: 2009-08-07
Publication date: 2010-02-18

Abstract

This invention relates to a construction element comprising a body, at least one channel formed in the body, and an optical component or components within each of the channel(s), wherein each channel(s) extends from a surface of the body and terminates within the body substantially at or toward to a region of the body located distal of the surface.

Description

A CONSTRUCTION ELEMENT

FIELD OF THE INVENTION

The present invention relates to a construction element and in particular, though not solely, to a construction element for use in collecting and/or storing solar energy

BACKGROUND TO THE INVENTION

The thermal insulation of buildings is desired for many reasons. Insulating a building or structure is beneficial in helping retain energy (heat) and minimise or reduce energy losses during cool(er) seasons, as well as minimising or reducing excessive energy (heat) gain by a building or structure during warm(er) seasons.

Energy may be inputted to a building or structure from a number of man-made means, for example from electrical heaters located within the building. Likewise, energy can be extracted or removed from a building or structure to affect cooling via, for example, the use of heat pumps such as air conditioning units extracting energy/heat from within the building and from the building structure materials. Both the healing and cooling of a building or structure in this manner is cosdy in terms of capital equipment and their associated operational costs, as well as the required consumption of natural resources to do so. Thus, insulating a building or structure can help in some way to reduce the total heating and cooling requirements needed to maintain substantially similar, or more consistent, temperatures within the building/structure.

In addition to the heating and/or cooling means which may be used to control the temperature of and within a building/structure, it is desirable to use energy which is naturally imparted from the sun, in die form of solar radiation, to provide or at least contribute to the heating requirements.

Solar radiation is the full spectrum of electromagnetic energy including visible light from the sun. When solar radiation strikes a solid surface or a transparent medium such as air or glass, some of the energy is absorbed and converted into thermal energy, some is reflected, and some is transmitted. All three of these effects may be used for an effective passive solar design. Utilising solar radiation to heat a building or structure during cool(er) seasons is understood and in some instances has been referred to as a passive solar heating system. Likewise, building materials having reflective surfaces to help reject solar from the surface of such material is understood.

The provision of a building material or construction element which is enabled to selectively collect or reject solar radiation at different angles of solar radiation incidence to the surface of the collection device would be advantageous. Such a solution would help contribute and/or may even meet the dual energy requirements of a building/ structure throughout the cool(er) and warm(er) seasons of the year. Such a solution would also allow a more constant temperature with less temperature fluctuations within the building/ structure.

Such a solution may also be provided to the end user in a ready-made form which does not require on-site manufacture or adjustment. Such a form provides a number of advantages. Additionally, advantages would be further conveyed if such a construction element could be utilised or contribute to the structural performance of a building/structure.

A building block comprising light transmitting fibres is disclosed in WO-A-03/097954. A cast material block (e.g. concrete) is formed having light transmitting fibres embedded within the material at the time of casting the block. The light transmitting fibres (e.g. optical or glass fibres) extend wholly from one lateral surface of the block to the opposing lateral surface, allowing light to be transmitted entirely through the block. The building block is defined as being a homogenous body, the body allowing light to be transmitted from one surface of the block to the opposing surface of the block for illuminating purposes. Such a building block is not selective in accepting or rejecting solar radiation at certain angles of incidence to the block surface.

US-B-5,511,537 discloses a cladding system in which a material is adapted to be affixed to external walls or surfaces of a structure and which is further adapted to absorb solar radiation during winter seasons and reflect solar radiation during summer seasons. Absorption of solar radiation occurs when the sun is at a relatively low position, relative to the surface to which the cladding is affixed. Reflection of solar radiation occurs when the sun is at a relatively high position, relative to the surface to which the cladding is affixed. However, such a system requires that it be used as a cladding, of which there are many disadvantages associated therewith. Such a cladding is not provided as a construction element nor does the cladding form or contribute to the structural performance of the building (the cladding must be supported by the building/structure itself).

In this specification where reference has been made to patent specifications, other external documents, or other sources of information, this is generally for the purpose of providing a context for discussing the features of the invention. Unless specifically stated otherwise, reference to such external documents is not to be construed as an admission that such documents, or such sources of information, in any jurisdiction, are prior art, or form part of the common general knowledge in the art.

It is an object of the present invention to provide a construction element and/or a construction element for use in collecting and/or storing solar radiation which will go at least some way towards addressing the foregoing problems or which will at least provide the industry and/or public with a useful choice.

As used herein the term "and/or" means "and" or "or", or both. As used herein "(s)" following a noun means the plural and/or singular forms of the noun.

SUMMARY OF THE INVENTION

In a first aspect, the present invention consists in a construction element comprising:

a body,

at least one channel formed in the body, and

an optical component or components within each of the channel(s),

wherein each channel(s) extends from a surface of the body and terminates within the body substantially at or toward to a region of the body located distal of the surface.

In a second aspect, the present invention consists in a construction system comprising:

one or more construction elements substantially adjoined to or adjoining one another, each said construction element comprising:

a body,

at least one channel formed in the body, and at least one channel formed in the body, and

an optical component or components within each of the channel(s), wherein each of the channel(s) extends from a surface of the body and terminates within the body at or substantially toward to a region of the body located distal of the surface.

Alternatively, in either or both of the above aspects the channel may be a cavity.

In yet a further alternative, the channel(s) or cavity(s) may be aligned horizontally or vertically or in any other orientation oriented and/or adapted to be configured to receive solar radiation.

Preferably, the construction element may be a pre-formed or prefabricated construction element. More preferably, the construction element may be in the form of a block or a panel.

Preferably, the surface may be an external or exterior facing surface of the body. For example, such a surface is that on the exterior of a building or structure available for incident solar radiation.

In one preferred embodiment of the present invention, where the construction element is in the form of a panel the channel(s) or cavity(s) may be oriented vertically relative to the horizontal. Even more preferably, the channel(s) or cavity(s) may extend substantially the height of the panel, or may extend partially the height of the panel. Yet even more preferred the channels(s) or cavity(s) may be displaced from one another in an even spacing across the width of the panel.

Preferably, the region located distal of the surface may be a thermal storage region.

Preferably, the region may be adapted to receive and/or store solar radiation.

Preferably, the region may have a heat capacity greater than the average heat capacity of the remainder of the body.

Preferably, the region may be formed of a material or materials having an average density greater than the average density of the material(s) forming the remainder of the body. More preferably, the region may be formed of a cementitious material with a density greater than about 2000 kg/m³ and/or a thickness greater than about 60 mm. It will be appreciated that

^■ density and thickness may be varied as necessary in order to achieve a desired level of thermal storage. For example, structural concrete (including the high density Portland cement concretes and inorganic polymer concretes used in stratified panels) and concrete grout may be used as thermal storage region materials.

Preferably, the body further comprises a layer(s) of insulation or insulating material.

Preferably, the layer of insulation or insulating material may be located between the surface and the region distal of the surface. For example, the insulation may be provided closer to the exterior surface side of the thermal storage region. The preferred R-value of the insulating layer(s) or material will depend on the climate of building/structure location and the desired energy performance of the building/structure. Preferably the R-value of the insulating layer(s) or material is greater than about 0.8 m².K/W. It will be appreciated that various R-value materials may be used in order to achieve a desired level of insulation.

Preferably, the solar radiation may be transmitted via the optical component or components. Preferably the optical component or components is comprised of a material with an extinction coefficient less than about 20 m^"1. Examples of suitable materials include, but are not limited to, one or more of polycarbonate, acrylic, semi-transparent plastic, semi-transparent glass, glass, cast glass, one or more of a series of bundled fibre-optic fibres.

Preferably, the optical component or components may be adapted and/or configured to selectively transmit solar radiation incident on the surface via the channel(s), or cavity(s), to the region of the body located distal of the surface. Such a region is located internally of the body.

Preferably the sides, bottom and top of the optical component may be reflective to solar radiation, to maximise the transmittance of solar radiation from the exterior surface of the optical component to the region distal of the body's surface. Preferably the optical component or components may be reflectors, such reflectors may be specular reflectors.

Preferably, the optical component or components may be adapted and/or configured to selectively transmit a greater proportion of incident solar radiation during the cool(er) season(s) when auxiliary heating energy is required to maintain the interior of the building/ structure at the desired temperature. Also preferably, the optical component or components may be adapted and/or configured to selectively transmit, relatively, a lesser proportion of incident solar radiation during the warm(er) season(s) when venting or cooling is required to maintain the interior of the building/structure at the desired temperature. Preferably the solar radiation rejected from a solar tube increases with increasing solar altitude, during the cooling season. Preferably solar radiation is not rejected from the solar tube during the heating season. Or, preferably, relatively,, a lesser amount of solar radiation is rejected from the optical component or components as solar attitude decreases. The solar altitude at which solar radiation is preferably rejected depends on the orientation of the wall and the climate of the building site.

For the purposes of this specification "solar altitude" means the angle of the centre of the solar disc above the unobstructed horizon. For the purposes of this specification "solar-wall azimuth" means the horizontal angle between the wall's normal vector and die sun in the sky.

The cross-sectional shape of the optical component is preferably rectangular but may be circular or any other suitable shape.

The seasonal variation of the solar transmittance of an optical component may be achieved by incorporating a pair(s) of solar reflectors within the optical component, adjacent to its exterior-facing surface. A pair of solar reflectors comprises a top reflector and bottom reflector that face each other. Preferably the reflectors are specular reflectors.

Preferably the width (dimension parallel to the exterior surface of the optical component) of the top and bottom reflectors in pair of reflectors within an optical component is approximately equal to the width of the optical component.

Preferably the bottom reflector in a pair of reflectors within an optical component, slopes upwards from the exterior surface of the optical component at an angle (θ) of about 15° to about 30° from the horizontal. Preferably the slope length of this reflector is approximately equal to Dsin(θ), where D is the maximum distance between the top and bottom reflectors in a pair of reflectors.

Preferably the top reflector in a pair of reflectors within an optical component is horizontal, or near horizontal. Preferably the length of the top reflector is approximately equal to Dsin²(θ), where D is the maximum distance between the top and bottom reflectors in a pair of reflectors and θ is the angle of the bottom reflector above the horizontal.

Preferably an optical component that incorporates more than one pair of reflectors is configured with no gap, or substantially no gap, between adjacent pairs of reflectors. In a third aspect, the present invention consists in a method of pre-forming or prefabricating a construction element comprising the steps of: i. forming a body having at least one channel or channels in a surface of the body, ii. forming or locating an optical component or components within each of the channel or channels, wherein steps i) and ii) occur either simultaneously or in a sequential manner, and wherein the channel(s) extend from the surface of the body and terminate within the body substantially at or toward a region of the body located distal of the surface.

Alternatively, the channel may be a cavity.

Preferably, the body is formed from a liquid-based mixture or material and is cured to a desired body configuration.

Preferably, the body is formed from substantially organic material(s) or from substantially inorganic material(s) or substantially from an admixture of both organic and inorganic material(s).

Preferably, the body is formed from a substantially cementitious-based material or mixture.

In a fourth aspect, the present invention may broadly consist in a method of construction comprising substantially connecting or substantially adjoining one or more construction elements to each other, the construction element(s) as defined in the first aspect.

In a fifth aspect, die present invention consists in a building or structure comprising one or more construction elements, the construction element(s) as defined in the first aspect or as formed according to the third aspect.

In a sixth aspect, the present invention consists in a prefabricated building block comprising a body, at least one channel formed in the body, and an optical component or components within each of the channel(s), wherein each channel(s) extends from a surface of die body and terminates widiin the body substantially at or toward to a region of the body located distal of the surface. In yet a further aspect, the present invention may broadly consist in a prefabricated panel comprising a body, at least one channel formed in the body, and an optical component or components within each of the channel(s), wherein each channel(s) extends from a surface of the body and terminates within the body substantially at or toward to a region of the body located distal of the surface.

The term "comprising" as used in this specification means "consisting at least in part of. When interpreting each statement in this specification that includes the term "comprising", features other than that or those prefaced by the term may also be present. Related terms such as "comprise" and "comprises" are to be interpreted in the same manner.

This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.

It is intended that reference to a range of numbers disclosed herein (for example, 1 to 10) also incorporates reference to all rational numbers within that range (for example, 1, 1.1, 2, 3, 3.9, 4, 5, 6, 6.5, 7, 8, 9 and 10) and also any range of rational numbers within that range (for example, 2 to 8, 1.5 to 5.5 and 3.1 to 4.7) and, therefore, all sub-ranges of all ranges expressly disclosed herein are hereby expressly disclosed. These are only examples of what is specifically intended and all possible combinations of numerical values between the lowest value and the highest value enumerated are to be considered to be expressly stated in this application in a similar manner.

The invention consists in the foregoing and also envisages constructions of which the following gives examples only.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention will be described by way of example only and with reference to the drawings, in which:

Figure 1 is a plan view of a cross-section through one embodiment of a construction element according to the present invention (grout not shown), and Figure 2 is a front view of a construction element according to the embodiment generally illustrated by Figure 1 (solar tube and grout not shown).

Figure 3 illustrates an embodiment of the optical components which may be utilised in the present invention, and

Figure 4 illustrates a further embodiment of the present invention in which an insulating layer and a thermal storage region are configured relative to each other (solar tube and grout not shown).

Figures 5A-5C illustrates solar radiation selectivity of one embodiment of an optical component according to the present invention at varying solar altitude angles and at a solar- wall azimuth of 0°.

Figures 6A-6C illustrates solar radiation selectivity of one embodiment of an optical component according to the present invention at varying solar altitude angles and at a solar- wall azimuth of 45°.

Figure 7A illustrates a plan view of one embodiment of the present invention formed as a panel.

Figure 7B illustrates a side view of an optical component suitable for use in the embodiment of Figure 7A.

Figure 7C illustrates an embodiment of an optical component and location of specular reflector.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The following description is made with reference to the accompanying Figures 1-6C and Figures 7A-7C. Figures 1-6C illustrate an embodiment of the present invention in the form of a block. Figures 7A and 7B illustrate an embodiment of the present invention in the form of a panel.

It should be noted Figure 1 does not show grouting in-situ, whilst Figures 2 and 4 do not show grouting or optical components (4) in-situ. In a first embodiment of the present invention, there is provided a construction element (1) comprising a body (2), at least one channel (3) formed in the body (2), and an optical component or components (4) within each of the channel(s) (3). Each of the channel or channels (3) extend from a surface (5) of the body (2) and terminate within the body (2) substantially at or toward to a region (6) of the body (2) located distal of the surface (5).

Such a construction element (1) can manufactured to yield a pre-formed or prefabricated element comprising die steps of (i) forming a body (2) having at least one channel or channels (3) in a surface (5) of die body and, (ii) forming or locating an optical component or components (4) within each of the channel or channels (3). The channel(s) (3) extend from die surface (5) of the body (2) and terminate within the body (2) substantially at or toward a region (6) of the body (2) located distal of the surface (5). Each of steps i) and ii) can be undertaken either simultaneously or in a sequential manner.

The body may be formed of any suitable construction materials, for example from cementitious-type materials or construction-grade polymeric materials or composites. The body may, in a first preferred embodiment, be substantially a masonry-type block. The block may be an existing block which is retro-fitted with die desired channel or channels off-site and the optical component or components incorporated therein as appropriate. Alternatively, trie body (2) may be formed by pouring a curable material into a suitable mould. The body can be poured and formed or formed from a single pour or may be formed from multiple pours or formed by jointing of multiple segments or sections which result in a body of an appropriate shape and configuration.

In another alternative, as shown in Figures 7A and 7B die body (2) can be in die form of a panel. As illustrated by these figures, there is at least one channel (3) or cavity into which an optical component (4) may be formed or located. The channel(s) or cavity(s) (3) can extend substantially the height of the formed panel. However, the channel(s) or cavity(s) may also extend only partially the height (or width) of the panel. Figure 7B illustrates one embodiment of an optical component (4) which may be utilised in the channel(s) or cavity(s) of die construction element (1) when in die form of a panel. It will also be recognised that such an optical component (4) as illustrated may also be utilised in a construction element of die present invention in alternative forms, such as a block. The seasonal variation of the solar transmittance of an optical component can be achieved by incorporating a pair(s) of solar reflectors within the optical component, adjacent to its exterior- facing surface, for example as illustrated in Figure 7B. In Figure 7B two pairs of reflectors are illustrated.

A pair of solar reflectors comprises a top reflector (9) and a bottom reflector (10) that face each other. Each reflector can be a specular reflector and can be coated appropriately to reflect incident light. The width (dimension parallel to the exterior surface of the optical component) of the top and bottom reflectors in pair of reflectors within an optical component can be approximately equal to the width of the optical component. In such an embodiment, the bottom reflector (10) in a pair of reflectors within an optical component (4), slopes upwards from the exterior surface of the optical component at an angle (θ) of about 15° to about 30° from the horizontal. The slope length of this reflector can be approximately equal to Dsin(θ), where, as previously mentioned, D is the maximum distance between the top and bottom reflectors in a pair of reflectors.

Further, the top reflector (9) in a pair of reflectors within an optical component (4) can be horizontal, or near horizontal and the length of the top reflector can approximately equal to Dsin²(θ). As previously mentioned D is the maximum distance between the top and bottom reflectors in a pair of reflectors and θ is the angle of the bottom reflector above the horizontal. In an alternative embodiment, there may be optical component that incorporates more than one pair of reflectors which is configured with no gap between adjacent pairs of reflectors; alternatively there may be a slight gap between the adjacent pairs of reflectors although this may not be most desired.

Reflectors (9, 10) can be cut from an acrylic mirror sheet. In one example, the top reflector's (9) surface may be inclined at about 20° from the horizontal, whilst the bottom reflector's (10) surface is at the horizontal (i.e. about 0° from the horizontal). The reflectors are insertable through channels (3) into the optical component (4).

Suitable casting operations may also be employed. In the example of composite materials, any moulding or casting method can advantageously be employed, for example casting on flat beds in the case of panels and block-making machines. Such an appropriate shape and configuration includes casting or moulding one or more channels (3) within the formed body (2). These channels (3) extend from the surface (5) of the body (2) at which the optical component(s) (4) is/are exposed and/or adapted to receive incident solar radiation (SR). Such a surface is generally an exterior surface of the - construction element. The channel(s) (3) extend through the body (2) and terminate at a depth within the body at or toward a region which is distal to the exterior surface. In one embodiment, the region is proximal to an interior surface of the body, that is, a surface which may be substantially an interior wall of a building or structure.

Such a region distal of the exterior surface of the body is preferably a thermal storage region. Advantageously, this region is adapted to enable storage of solar energy.

In this manner, thermal energy stored in the region (6) can be transmitted to an interior of the building or structure. Alternatively, the stored energy in the form of heat can maintain the temperature of an interior building or structure wall or other surface.

Further to the embodiment above, the thermal storage region (6) can be formed of materials which are of a relative average density greater than the average density forming the remainder of the body (2). This can be achieved via the use of appropriately more dense materials than the remainder of the body. For example, more dense aggregate and cementitious materials may form the thermal storage region, whereas less dense aggregate and less dense cementitious materials may then form the remainder of the body, or for e'xample concrete grout or similar. Alternatively, when the construction element is for example in the form of a panel, the panel may be formed of a stratified material upon curing or may have a varied density across the thickness of the panel (from outside surface to internal surface).

Solar radiation absorbed within the region (6), for example when in the form of a system such as a constructed wall of one or more construction elements (1) raised its temperature, which reduces heat flow from, for example, adjacent room to wall and reduces or may help to minimising overall building heating energy requirements during cool(er) seasons.

In a further optional embodiment of the present invention, an insulation material or insulating layer of material may be formed with or fitted to the body located between the internal side of the body's exterior surface (5) and the region (6). Advantageously, such an insulating layer (7) aids to minimise the transmission of energy (in the form of heat) from being conducted through the body to the region (6) and from transmission through the body (2) to the interior surface of the body (2). Such an advantage can be particularly useful during warm(er) seasonal periods to aid insulation of the building/structure from heat exterior to the building/structure. In addition, the region (6) when acting as a thermal storage region can perform as a heat sink. Desirably, the region when acting as a heat sink can absorb some heat which may be transmitted to it from interior of the building/structure, or from heat which is transmitted from the exterior surface of the body (2). In this manner, advantageously the construction element (1) aids or goes some way towards aiding to insulate the interior of a building/structure when at least partially surrounded or enclosed by one or more such construction elements (1).

Likewise, during periods of cool(er) seasons, the region (6) the insulating layer (7) can aid in the reduction in the loss of energy from the storage region in the form of heat. Advantageously, this allows heat which is collected in the storage region (6) to be maintained for longer periods of time and may therefore beneficially maintain the internal temperature of a building or structure which is surrounded or at least partially surrounded by one or more such a construction element (1).

Examples of insulating materials comprise polystyrene and other known materials of polyurethane and polyisocyanurate. The insulating layer may also be a low density concrete, advantageously with a thermal conductivity less than 0.2 W/m.K. Preferably the insulation layer has an R- value (thermal resistance) of greater than about 0.8 m².K.W^"'. The insulation may for example be polystyrene or a foamed-type material.

The channels (3) may be of a shape and configuration suitable to accommodate the optical component or components (4). For example, the channels may be of a cross section such as a slot (i.e. rectangle), cylindrical, square, oblong or any polygonal shape. Such a cross-sectional shape may extend the length of the channel to the point of termination distal of the surface (5) of the body (2).

The optical component or components (4) may be in the form of a tube, which may, for the purposes of this specification, also be referred to as a "solar tube". Such optical component or solar tube may be at least a semi-transparent material that has properties sufficient to allow transmission of solar radiation incident to the optical component. Such optical component or solar tube can be constructed from a semi-transparent material with one or more enclosed cavities, which reduce the heat flow from a wall to the environment via the optical component or solar tube. Solar tubes advantageously penetrate the surface (5) of the body (2) and may (where included as an optional feature) penetrate the insulation layer (7) to transmit solar radiation from the exterior surface to the thermal energy storage region or layer (6), such as dense concrete. Beneficially it is hypothesised that solar radiation absorbed by the storage region (6) is significantly more effective in reducing building heating energy requirements than radiation absorbed by exterior surface of a wall.

Examples of suitable materials forming the optical component or solar tube may be one or a series of bundled optical fibres, glass, optically transparent polymer materials such as polycarbonates or acrylics or similar.

In a further example, a semi-transparent coating such as polytetrafluoroediylene, (such as Teflon™) may be used as a reflecting surface (utilising internal reflection at the boundary between coating and tube). In this case it is preferable that the solar tube refractive index is at least 0.1 greater than that of the coating.

A solar tube may comprise an outer extruded plastic section glued or otherwise attached into a slot or cavity in an outer surface of a block. An inner extruded plastic section may then fit snugly into a corresponding slot or cavity which passes or extends through the insulation layer (if present). A further slot or cavity connects the two plastic sections.

In the case of a panel embodiment of the present invention, a solar tube may comprise an extruded plastic section glued into a slot which has been cast in the outer (exterior exposed) surface of a concrete panel.

Furthermore, the optical component or solar tubes may be formed of a material which is coated in a reflective coating (8) or substrate or suitably reflective composition which allows solar radiation entering the optical component/ solar tube to be effectively reflected through the component/tube to the termination point of the channel within the body of the construction element (1). Such coating or reflective material can be used to reduce the "leakage" of solar radiation through the sides of the optical component/solar tube and thus increase the solar radiation transmitted to the storage region (6). Such a coating acts like a mirror provided its refractive index is less than that of the optical component/ solar tube material and the solar rays/solar radiation striking the coating or material is with an angle of incidence greater than the critical angle. For example, Figure 7C illustrates one embodiment of an optical component (4) or solar tube, where the dashed lines indicate the location of reflective material or reflective coating (8), such as a specular reflector. Such a reflective tape or foil or paint is located on the outside (or inside) surface of the optical component (4) — reflective surfaces facing the channel (3) of the optical component (4).

The optical component (4) may be formed of a semi-transparent plastic such as an acrylic(s). Further, an optical component (4) may comprise of an outer extruded plastic section glued into a (vertical or otherwise) slot in the outer shell of a construction element and an inner extruded plastic section that fits snugly into a corresponding slot, for example in the insulation layer. The channel (3) which forms the slot in the insulation connects the two plastic sections forming the optical component (4).

With particular reference to Figures 1-4, there is shown one particularly preferred embodiment of the present invention. In such an embodiment, the construction element is in the form of a- block, preferably for example, a masonry block with an inner structurally, reinforced side and an outer weather-resistant side, separated by a discontinuous layer of insulation. The solar tube, or optical component, is positioned to allow solar energy to pass through the outer weather resistant face and the insulation, to be stored in the internal structural layer. The masonry unit may be cast from generally normal weight concrete (i.e. from at least about 2400 kg/m3 to about 2000 kg/m3) or lightweight concrete (about 1,950 kg/m3 to about 1,150 kg/m3, or even less), but the concrete filling the cores of the internal reinforced with of the wall should be normal density concrete (about 2,300 kg/m3 to about 2,500 kg/m3) to provide energy storage.

Such an embodiment utilises optical components in the form of solar tubes. The solar tubes can be of a two-part or multi-part construction, for example as clearly illustrated in Figures 1 and 3.

In the manner described above, advantageously the optical component/solar tubes used mean that solar rays or solar radiation with relatively low solar altitude are reflected through the component/tube and received within the region (6). Because of this, solar tubes are more effective in transmitting solar radiation to the region (6) during winter periods of relatively low solar altitude, when heat is desired, than during summer, when the collection of- solar heat is less desired. In a further alternative, a low-cost solar tube may be constructed by forming the channel or cavity in the body (2) and plugging the cavity or channel with a layer of optically semi- transparent material. The plug may be solid or formed with an enclosed cavity.

Solar tubes may be constructed with varying shapes and sizes. A cylindrical tube may be used in larger concrete-type panels, for example when forming the construction element of the present invention as a panel.

The total effect of solar tubes on wall energy performance depends on the design of the solar tube, the fraction of the wall's surface covered by the solar tubes, wall orientation to the rotational pathway of the sun (i.e. solar-wall azimuth), local climate conditions, the climate within the building and the solar transmittance of any paint finishes. Solar tube design and/or the fraction of the wall covered by solar tubes can be varied to achieve a target wall energy performance. It is hypothesised that less than about 20% of the exterior surface (7) of the construction element may need to be exposed to solar radiation with optical component(s) receiving such solar radiation /solar rays.

Reference is also made to Figures 5A-5C which illustrates one preferred embodiment of the optical component of the present invention; incoming solar radiation is indicated by arrows 'SR'. In one preferred embodiment of the present invention, solar radiation (SR) may strike the optical component (4) at incidence angles of about 70°, about 50° and about 30°, as shown illustratively in Figures 5A, 5B and 5C, respectively. The embodied solar radiation examples of Figures 5A-5C are conducted in each case at a solar-wall azimuth of about 0°. Preferred rejection of solar radiation and transmission into the optical component/solar tube are also illustratively shown in these figures.

Reference is also made to Figures 6A-6C which illustrates one preferred embodiment of the optical component of the present invention; incoming solar radiation is indicated by arrows 'SR'. In a preferred embodiment of the present invention, incoming or incident solar radiation (SR) strikes the optical component (4) at incidence angles of about 45°, about 30° and about 15° in Figures 6A, 6B and 6C, respectively, as illustratively shown. The solar tube/optical component embodiments of Figures 6A-6C are shown in each case at a solar- wall azimuth of about 45°. Preferred rejection of solar radiation and transmission into the optical component/solar tube are also illustratively shown in these figures.

The solar-wall azimuth affects the solar altitude at which rejection of solar radiation begins. Figures 5A-5C and 6A-6C help to demonstrate the selectivity of an optical component which may be used in the present invention. For example, Figures 5C and 6C clearly illustrate that solar radiation incident at the angle of those figures is reflected wholly within the optical component and thus allowed to be transmitted via the optical component and channel (which may be lined with a reflective coating of the optical component does not itself extend the entire length of the channel) to the region (6). Such total internal reflection preferably allows nearly 100% transmission of solar radiation (apart from any losses of the system). In contrast, the Figures of 5A and 6A more clearly demonstrate only partial transmission of solar radiation via the optical component, with a majority of incident solar radiation is reflected back out of the optical component. Such rejection of solar radiation is preferred at relatively high solar altitudes, depends on the solar-wall azimuth. Figures 5B and 6B demonstrate an intermediate level of solar radiation rejection compared to Figures 5A, 5B, 6A and 6B.

Tables 1 and 2, respectively, demonstrate the solar radiation selectivity of the optical components in Figures 5A-5C and Figures 6A-6C.

Table 1: Physical characteristics of solar radiation selectivity for Figures 5A-5C.

Table 2: Physical characteristics of solar radiation selectivity for Figures 6A-6C.

A construction element as described above may be formed in a prefabricated manner, i.e. not in-situ during construction of a building. This advantageously allows manufacturing benefits of forming such a construction element (1). A building or structure, such as external walls, can then be constructed. The construction element (1) is preferably formed of suitable structural materials enabling the element (1) to contribute to the structural performance of the building, or at least to provide greater structural performance than a cladding.

Whole or partial structures may be formed of one or more construction elements (1). The actual size of the construction element may vary depending upon the application. Large panels may be formed, or smaller block-type construction elements may be formed. Where large panels are to be formed, pre-cast concrete panel construction methods may be suitable employed and modified as appropriate, and in conjunction with the method of the present invention.

Example 1:

With reference to the annotated drawings and dimensions A-O, a construction element in the form of a block can be formed, where dimensions A-O are:

-A: 150 mm; B: 390 mm; C: 35.5 mm; D: 38 mm; E: 45 mm; F: 35 mm; G: 123 mm; H: 110 mm; I: 13 mm; J: 80 mm; K: 170 mm; L: 100 mm; M: 35 mm; N: 120 mm.

The high density concrete material has a density of about 2000 kg.m ³. The low(er) density concrete material has a density of about 1000 kg.m^" . The insulation layer is polystyrene and has a 35 mm x 110 mm slot cut or formed in the insulation material for receiving of the optical components (4). Figures 2 and 4 do not illustrate optical components or grouting in- situ.

Example 2:

With reference to Figure 7A, there is illustrated a part of a panel or wall comprising the present invention, the channels (2) with optical components (4) located vertically across the width of the panel, spaced at about 350 mm centres from each other.

The foregoing description of the invention includes preferred forms thereof. Modifications may be made thereto without departing from the scope of the invention.

Claims

CLAIMS:

1. A construction element comprising: a body, at least one channel formed in the body, and an optical component or components within each of the channel(s), wherein each channel(s) extends from a surface of the body and terminates within the body substantially at or toward to a region of the body located distal of the surface.

2. The element as claimed in claim 1, where the surface is an external or exterior facing surface of the body.

3. The element as claimed in claim 1 or claim 2, wherein the construction element is a pre-formed or prefabricated construction element.

4. The element as claimed in any one of claims 1 to 3, wherein the construction element is in the form of a block or a panel.

5. The element as claimed in any one of claims 1 to 4, wherein the construction element in the form of a panel includes the at least one channel oriented substantially vertically relative to the horizontal, the channel extending substantially the height of the panel, or at least partially the height of the panel.

6. The element as claimed in claim 4 or claim 5, wherein the channels are displaced from one another in an even spacing across the width of the panel.

7. The element as claimed in any one of claims 1 to 6, wherein the region has a heat capacity greater than the average heat capacity of the remainder of the body.

8. The element as claimed in any one of claims 1 to 7, wherein the region is formed of a material or materials having an average density greater than the average density of the material(s) forming the remainder of the body.

9. The element as claimed in any one of claims 1 to 8, wherein the region is formed of a cementitious material with a density greater than about 2000 kg/m¹ and/or a thickness greater than about 60 mm.

10. The element as claimed in any one of claims 1 to 9, wherein the region located distal of the surface is a thermal storage region.

11. The element as claimed in any one of claims 1 to 10, wherein the body further comprises a layer(s) of insulation or insulating material.

12. The element as claimed in claim 11, wherein the layer of insulation or insulating material is located between the surface and the region distal of the surface.

13. The element as claimed in claim 11 or claim 12, wherein the insulating layer(s) or material has an R- value of greater than about 0.8 m².K/W.

14. The element as claimed in any one of claims 1 to 13, wherein the optical component or components is a solar radiation transmitter.

15. The element as claimed in any one of claims 1 to 14, wherein the optical component is comprised of a material with an extinction coefficient less than about 20 m^"1.

16. The element as claimed in any one of claims 1 to 15, wherein the optical component is comprised of one or more of polycarbonate, acrylic, semi-transparent plastic, semi-transparent glass, glass, cast glass, one or more of a series of bundled fibre-optic fibres.

17. The element as claimed in any one of claims 1 to 16, wherein the optical component or components selectively transmits solar radiation incident on the surface via die channel(s) to the region of the body located distal of the surface.

18. The element as claimed in any one of claims 1 to 18, wherein the channel is formed of, or houses, one or more, or a series of the optical component or components.

19. The element as claimed in any one of claims 1 to 18, wherein the channel(s) is aligned substantially horizontally or substantially vertically or in any other orientation oriented and/or adapted to be configured to receive solar radiation.

20. The element as claimed in any one of claims 1 to 19, wherein the channel(s) has substantially a rectangular, cylindrical, square, oblong cross-section.

21. The element as claimed in any one of claims 1 to 20, wherein the sides, bottom and top of the optical component are reflective to solar radiation.

22. The element as claimed in any one of claims 1 to 21, wherein the optical component or components comprises or includes one or more reflectors.

23. The element as claimed in claim 22, comprising at least a pair of reflectors within die optical component, the reflectors substantially adjacent to the surface.

24. The element as claimed in claim 22 or claim 23 wherein a pair of reflectors comprises a top reflector and bottom reflector facing each other.

25. The element as claimed in claim 24, wherein the width of the top and bottom reflectors in a pair of reflectors within an optical component is approximately equal to the width of the optical component.

26. The element as claimed in claim 24 or claim 25, wherein the bottom reflector in a pair of reflectors within an optical component slopes upwards from the exterior surface of the optical component at an angle (θ) of about 15° to about 30° from the horizontal.

27. The element as claimed in claim 26, wherein the slope length of the bottom reflector is approximately equal to Dsin(θ), where D is the maximum distance between the top and bottom reflectors in a pair of reflectors.

28. The element as claimed in any one of claim 24 to 27, wherein the top reflector in a pair of reflectors within an optical component is horizontal, or substantially near horizontal.

29. The element as claimed in any one of claims 24 to 27, wherein the slope length of the top reflector is approximately equal to Dsin²(θ), where D is the maximum distance between the top and bottom reflectors in a pair of reflectors and θ is the angle of the bottom reflector above the horizontal.

30. The element as claimed in any one of claims 24 to 29, wherein an optical component incorporating more than one pair of reflectors is configured with no gap between adjacent pairs of reflectors.

31. The element as claimed in any one of claims 22 to 30, wherein the reflector or reflectors is/are a specular reflector.

32. The element as claimed in any one of claims 1 to 31, wherein the optical component or components is selectively capable of transmitting: i. a greater proportion of incident solar radiation during the cool(er) season(s), and ϋ. relatively a lesser proportion of incident solar radiation during the warm(er) season(s).

33. The element as claimed in any one of claims 1 to 32, wherein solar radiation is increasingly rejected from the optical component or components with an increasing solar altitude, and relatively, a lesser amount of solar radiation is rejected from the optical component or components as solar attitude decreases.

34. The element as claimed in any one of claims 1 to 33, wherein the channel is a cavity.

35. A construction system comprising: one or more construction elements substantially adjoined to or adjoining one another, each said construction element comprising: a body, at least one channel formed in the body, and an optical component or components within each of the channel(s), wherein each of the channel(s) extends from a surface of the body and terminates within the body at or substantially toward to a region of the body located distal of the surface.

36. The construction system as claimed in claim 35, wherein the construction element is defined by claims 1 to 34.

37. A method of pre-forming or prefabricating a construction element comprising the steps of: forming a body having at least one channel or channels in a surface of the body, forming or locating an optical component or components within each of the channel or channels, wherein steps i) and ii) occur either simultaneously or in a sequential manner, and wherein the channel(s) extend from the surface of the body and terminate within the body substantially at or toward a region of the body located distal of the surface.

38. The method as claimed in claim 37, wherein the channel is a cavity.

39. The method as claimed in claim 37 or claim 38, wherein the body is formed from a liquid-based mixture or material and is cured to a desired body configuration.

40. The method as claimed in any one of claims 37 to 39, wherein the body is formed from substantially organic material(s) or from substantially inorganic material(s) or substantially from an admixture of both organic and inorganic material(s).

41. The method as claimed in any one of claims 37 to 40, wherein the body is formed from a substantially cementitious-based material or mixture.

42. A method of construction comprising substantially connecting or substantially adjoining one or more construction elements to each other, the construction element(s) as defined in any one of claims 1 to 34.

43. A building or structure comprising one or more construction elements, the construction element(s) as defined in any one of claims 1 to 34.

44. A prefabricated building block comprising: a body, at least one channel formed in the body, and an optical component or components within each of the channel(s), wherein each channel(s) extends from a surface of the body and terminates within the body substantially at or toward to a region of the body located distal of the surface.

45. A prefabricated panel comprising: a body, at least one channel formed in the body, and an optical component or components within each of the channel(s), wherein each channel(s) extends from a surface of the body and terminates within the body substantially at or toward to a region of the body located distal of the surface.

46. A construction element substantially as hereinbefore described and as illustrated with reference to any one of the accompany drawings.

47. A construction system substantially as hereinbefore described and as illustrated with reference to any one of the accompany drawings.

48. A method of pre-forming or prefabricating a construction element substantially as hereinbefore described and as illustrated with reference to any one of the accompany drawings.

49. A method of construction substantially as hereinbefore described and as illustrated with reference to any one of the accompany drawings.

50. A building or structure substantially as hereinbefore described and as illustrated with reference to any one of the accompany drawings.

51. A prefabricated building block substantially as hereinbefore described and as illustrated with reference to any one of the accompany drawings.

52. A prefabricated panel substantially as hereinbefore described and as illustrated with reference to any one of the accompany drawings.