[001] The present invention relates to energy recovery apparatus for use with lighting systems.

[002] Lighting systems of one form or another are incorporated into many surroundings in people's lives. These lighting systems require energy to operate. When the lighting systems receive energy they generate light, but also heat as by-product. Such heat can be useful in certain limited applications, such as when particular lamps are used for keeping food warm, but for the most part such heat energy is lost and thereby wasted. [003] The present invention is in this respect directed towards recovering and harvesting the heat energy lost in such systems .

[004] According to an aspect of the present invention there is provided apparatus for collecting energy within a powered lighting system, said apparatus comprising: - a light source; and

energy collector means which is disposable at or adjacent the light source, wherein the energy collector means is configured to recover heat energy produced by the light source .

[005] In this connection, such apparatus allows recovery of heat energy which would otherwise have been wasted.

[006] Such recovered heat energy can be used as one or more of a source of power, a source of heating, a means for heating water, a means for cooling, a means for dehumidification, a means for desalination or a means for desiccation. [007] Conveniently, the energy collector means comprises a thermoelectric element. [008] Preferably, the thermoelectric element is a thin film element, a thick film element or an organic element.

[009] Conveniently, the energy collector means collects both low grade energy and high grade energy. In this regard, different lighting systems generate different intensities of heat energy. The energy collector means is hence configured to tolerate different types of heat energy for recovery so that the energy savings can be optimally comprehensive and efficient .

[0010] Conveniently, the apparatus further comprises a heat exchanger. In this way, the heat energy can be more efficiently recovered from the light source. [0011] Preferably, the energy collector means is positioned between the light source and the heat exchanger. In this way a temperature drop is promoted across the energy collector means, thereby improving its effectiveness. [0012] Conveniently, the heat exchanger comprises a fluid filled manifold for supplying fluid to a plurality of thermoelectric elements which are positioned adjacent said light source. [0013] Fluid from the heat exchanger can be used directly or indirectly for various purposes making the energy saving more efficient and the use of recovered energy more versatile. For example, warm or hot water can be provided directly from the heat exchanger. [0014] Conveniently, the apparatus further comprises a flexible heat sink.

[0015] Conveniently, the apparatus further comprises air flow means for directing an air flow past said light source into a designated space.

[0016] The air flow can be controlled so that said space can be heated, ventilated or humidified depending on the requirements of the user.

[0017] Preferably, air flow channels are provided for guiding air flow around the light source. Conveniently said air channels run between the light source and the energy collector means.

[0018] Conveniently, the light source is a light bulb.

[0019] According to a further aspect of the present invention there is provided lighting apparatus, said lighting apparatus comprising: - a light source;

energy collector means which is disposable at or adjacent the light source,

heat exchanger means provided at or adjacent the energy collector means; and

fan means for directing an air flow through air flow channels provided between the light source and the heat exchanger means .

[0020] Preferably, the lighting apparatus comprises a centrally disposed light source, with thermoelectric elements disposed outwardly therefrom, and with heat exchanger elements disposed outwardly from said thermoelectric elements . [0021] Illustrative embodiments of the present invention will now be described with reference to the accompanying drawings, in which:

[0022] Figure 1 shows a schematic view of a first embodiment of the present invention;

[0023] Figure 2 shows a schematic view of a second embodiment of the present invention;

[0024] Figure 3 shows a schematic view of a third embodiment of the present invention; [0025] Figure 4 shows a schematic view of a fourth embodiment of the present invention;

[0026] Figure 5 shows a schematic view of a fifth embodiment of the present invention; and

[0027] Figure 6 shows a schematic view of a sixth embodiment of the present invention.

[0028] Figures 1 to 6 show a light system 10 comprising a light source 1, and at least one energy collector 3 which is disposed in close proximity at or adjacent the light source 1.

[0029] In the embodiments of Figures 1 and 2, the light source 1 may be relatively efficient lighting, such as LED lighting, which generates low grade heat. Figure 3 relates to less efficient lighting such as used in street or stadium lighting . [0030] The energy collector 3 may comprise a thermoelectric element. The thermoelectric element can be made of thin or thick film elements depending on situation. Furthermore, as shown in Figure 4 the thermoelectric element may also be made of organic materials.

[0031] Figures 1 and 2 further show the energy collector 3 as at least partially surrounding the light source 1. The energy collector 3 is thus disposed centrally between the light source 1 and heat sinks 2.

[0032] As there is a temperature difference between surface of the light source 1 and the heat sink 2, the energy collector (thermoelectric element) 3 is able to recover wasted low grade heat and convert this to electrical energy. The energy collector 3 (thermoelectric element) is connected to an electrical circuit 5 (partially shown) so that the wasted energy can be collected, stored or used if necessary.

[0033] As shown in Figure 2, a fan 7 sets up an air flow in channels provided between the light source 1 and the energy collector 3. This air can be directed into or from a space to provide a heating or cooling effect on the space as required . [0034] Figure 3 illustrates a light system 10 which has a light source 1 which generates high grade heat. Such light source may be found in sports lighting, street lighting and industrial lighting systems. Once again, at least one energy collector 3 is provided in close proximity of the light source 1. The energy collector 3 at least partially surrounds the light source 1 so that the wasted heat energy can be efficiently recovered.

[0035] In the embodiment of Figure 3, the apparatus further comprises a heat exchanger having heat exchanger elements 9. The heat exchanger is positioned outwardly of the thermoelectric element 3, so that the energy collector elements 3 are disposed between the light source 1 and the heat exchanger elements 9.

[0036] The heat exchanger is connected to a passage 11 in which a fluid flows in from a predetermined direction (as indicated by the arrow) . The fluid flows in at a relatively low temperature. In passing through the heat exchanger elements 9, some of the excess heat energy wasted by the lighting system 10 is passed to the fluid. This can then be harvested from the fluid as appropriate.

[0037] The wasted heat energy is also collected by the thermoelectric elements 3 which can generate electricity (power) .

[0038] Figure 4 shows a light source 1 with an organic thermoelectric element which is formed by coating a flexible substrate with a patterned contact material and printing a thermoelectric material on top of the patterned contact material. In this way, p- and n- type legs are formed. Gaps between the TE legs are further filled up with a dielectric substance and a respective counter contact is coated on top. An encapsulation layer can be further coated onto the flat surface. This formation allows a flexible thin heat sink to be used to dissipate heat. The flexible thin heat sink may be made of polymer. [0039] Figure 5 shows an example of the apparatus wherein the light source is immersed in water. For example, the above-described apparatus can be used as fountain lights. The energy collector 3 can generate electricity from the temperature difference between water and the light source. In this case, the heat dissipates within water which results in self-cooling of the apparatus.

[0040] Figure 6 shows an example of the above-described apparatus being used in the floor/ground. In such a case , as the heat dissipates to the floor/ground, the energy collector generates electricity from the difference in the temperature of the floor/ground and the light source.

[0041] The light system 10 illustrated in Figures may be installed in a building where the energy collector 3 may supply required energy to drive HVAC systems within the building or the lighting system 10 may be incorporated as a part of the HVAC systems. By incorporating the lighting system 10 it is possible to generate power, to provide heating/cooling or provide water. Furthermore, dehumidifying of a given space is also possible. Taken in the industrial situation, such light systems can provide means to power desalination or to support desiccant processes by recovering the otherwise wasted heat energy.

[0042] It will be understood that the described embodiments relate to preferred examples of the invention and that the present invention encompasses variants that fall within the scope of the appended claims.