Solar heat absorber panels

Abstract

An array of panels absorptive to solar radiation 21 is made up of individual panels 24, 25 etc. A duct runs along a panel 25 and terminates near the edge of the panel as a terminals 27. This terminal is positioned so that it shares a common axis with a second terminal on a second panel 24, whereby the terminals may be brought into close proximity and connected with a connector 26. This connection may be made by sliding one panel along the axis of its terminal towards a second panel.

Description

This applications claims priority from UK patent application number 0314232 filed on Jun. 19, 2003.

BACKGROUND OF THE INVENTION

Many different kinds of solar heat exchange panels are known. Conventional flat plate panels have the disadvantage in that they normally lie over the roof covering, and are thus visually obtrusive and not easy to fit in the form of an array.

My international patent application PCT/GB01/04440 describes panels which are integrated into a roof or wall covering and linked by a fluid duct. This application discloses some advantageous improvements which may be made to the system, and in particular to the method of connecting absorber panels together.

SUMMARY OF THE INVENTION

This invention concerns heat exchange panels of the type used for absorbing solar radiation and using it to heat water. More specifically it concerns that type of panel designed to be fitted as an array to a wall or roof face.

Thus according to the invention there is a plurality of panels absorbent to solar radiation laid adjacent to each other, a duct for a heat transfer medium running along each said panel, each duct having a terminal which is substantially cylindrical in form, said terminals positioned so that a terminal on one panel is adjacent to and shares a common axis with a second terminal on a second panel, whereby the terminals may be connected together.

The panels are best placed on a roof or wall face orientated generally towards the equator, and they ideally have a coating which is highly absorptive to solar radiation. The panels my be made of aluminium, stainless steel, copper, plastic or other suitable material.

The panels may be arranged adjacent to each other in rows, and a number of rows may be arranged next to each other so as to form an array of panels. One way of achieving this is to support the panels in the rows by means of a number of horizontal battens of wood or suitable alternative material. The panels may overlie these battens, and a portion of batten between two adjacent panels may be left uncovered to receive fasteners to hold a covering of translucent or transparent roofing tiles, slates or shingles. Such a covering will let solar radiation pass through onto the panels, while preventing heat loss to the external air. Alternatively the panels may be made to overlap each other so they themselves form a covering impermeable to precipitation.

The duct carries a heat transfer medium, such as water, a water mixture or other fluid, along a panel so as to collect the solar energy absorbed by it. One advantageous way of arranging this is by means of a pipe welded, glued or otherwise attached to the panel, whereby energy absorbed by the panel in the form of heat is transmitted to the transfer medium in the pipe. The duct may preferably be made of copper, although other metals or plastics may be used. An alternative arrangement is by means of a panel which embodies a duct, such as a double skin metal absorber, or a plastic absorber with ducts moulded into it, but still having the function of transmitting energy from the panel to the transfer medium in the duct.

The means of connection of the panels is important, as connections need to be reliable and easy to achieve while working on a roof. This invention provides for this by having duct terminals at the edges of the panels, positioned so that when two panels are placed adjacent to each other the terminals line up and thus may be connected with a suitable connector. An advantageous method is to use a normal push fit pipe connector which may be fitted to one terminal, the other terminal then being pushed into it. If the panels are arranged in a horizontal row, with the terminals on the ends of the panels and on an axis parallel to the row, then making the connections is facilitated by being able to slide one panel along the battens towards another panel, whereupon the terminals line up and may be pushed into a connector. This connector may be a discrete item, or may be attached to one or both of two adjacent panels.

An insulating layer may be placed behind the panels to reduce heat loss from the rear. A waterproof membrane may be placed behind the panels catch any water penetrating through the panels. Such a membrane may be damaged by ultraviolet radiation from the sun, and so it is advantageous to provide a barrier to this radiation. This barrier may be provided by means of offsetting the gaps between panels, and the gaps in the insulation layer, so a gap in one layer does not coincide with a gap in another. This may be achieved by attaching the insulation layer to the panels, but offset slightly in one direction.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a plan view of a single absorber panel.

FIG. 2 shows an array of absorber panels.

FIG. 3 shows a cross section of a roof covered with absorbers.

FIG. 4 shows a cross section of a roof and absorbers, with a covering of glass slates.

DETAILED DESCRIPTION

The invention will now be described, by way of example only, with reference to the accompanying drawings.

Referring first to FIG. 1, an absorber panel 11 is made of an aluminium sheet 12 coated in a coating absorptive to solar radiation, to which is welded a copper pipe 13. The pipe 13 traverses the sheet in a serpentine manner, and both ends are terminated at the edge as terminals 15 and 15a. The panel is cut away 16, 16a to allow space for connectors (not shown). An insulation board 14 is attached to the rear of the panel and protrudes at one end so that it underlies the gap between this panel and a second panel placed adjacent to it, so as to provide a barrier to light passing through the gap between the panels.

FIG. 2 shows an array of panels 21 formed of a number of horizontal rows of panels (three rows are shown). The panels are supported by horizontal battens (not shown) along the lines of the panel edges 28, 28a. Note the gaps 22, 22a between the panels which allows fixings for tiles, slates or shingles to be fixed directly into the battens. The duct terminals are joined by connectors as shown at 23. During installation a panel 25 is placed on the battens near to a panel already installed 24. Panel 24 has had a connector 26 fitted to its duct terminal. The panel 25 is moved towards the panel 24 whereupon the terminal 27 slides into the connector 26 to form a water tight seal. A fluid such as water may then be passed through the array of panels for the purpose of collecting the heat absorbed when the sun shines on the panels.

FIG. 3 shows a cross section of roof with rafters 31 supporting battens 32, 32a. A waterproof membrane is placed between the rafters and the battens in a well known manner. On the battens are laid panels 33, 33a, 33b which consist of aluminium sheet 34 with a duct 35 fixed to it on the underside. An insulation board 36 is fitted between the battens. Gaps 37 are left between the panels. Thus an effective solar collector is built up on the roof.

FIG. 4 shows a roof with panels, similar to that in FIG. 3, with the addition of a transparent covering in the form of glass slates 41, 41a, 41b, 41c etc. These prevent loss of heat from the panels to the outside. The slates are held by clips 42, 42a which are fastened to the battens with fixings 43, 43a which pass through the gap 46 between two adjacent panels. To create an insulating air gap between the panels and the slates, the top edges of the slates rest on a spacer consisting of a ridge of silicone or other suitable material 44, 44a.

Claims

1. A plurality of panels absorbent to solar radiation laid adjacent to each other, a duct for a heat transfer medium running along each said panel, each duct having a terminal which is substantially cylindrical in form, said terminals positioned so that a terminal on one panel is adjacent to and shares a common axis with a second terminal on a second panel, whereby said terminals may be connected together.

2. A plurality of panels as claimed in claim 1 wherein the panels are arranged in substantially horizontal rows.

3. A plurality of panels as claimed in claim 2 wherein the panels are supported in the rows by a plurality of horizontal battens.

4. A plurality of panels as claimed in claim 3 wherein the panels overlie the battens.

5. A plurality of panels as claimed in claim 4 wherein a portion of batten between two adjacent panels is left uncovered to receive a fastener.

6. A plurality of panels as claimed in claim 2, 3, 4 or 5 wherein the axes of the terminals are substantially parallel to the rows.

7. A plurality of panels as claimed in any proceeding claim wherein a first panel may be moved along a row of panels towards a second panel, whereby a terminal on the first panel moves into sealing engagement with a terminal on the second panel.

8. A plurality of panels as claimed in any proceeding claim wherein the terminals of two adjacent panels are connected with a connector.

9. A plurality of panels as claimed in claim 8 wherein a terminal is pushed into a connector and forms a sealing engagement therewith.

10. A plurality of panels as claimed in any proceeding claim wherein the duct comprises a pipe attached to the panel.

11. A plurality of panels as claimed in claim 10 wherein the pipe is made of copper.

12. A plurality of panels as claimed in any proceeding claim wherein the panels embody the ducts.

13. A plurality of panels as claimed in any proceeding claim wherein the panels are coated with a layer highly absorptive to solar radiation.

14. A plurality of panels as claimed in any proceeding claim wherein the panels are made of aluminium.

15. A plurality of panels as claimed in any proceeding claim wherein the panels are covered with a layer translucent or transparent to solar radiation.

16. A plurality of panels as claimed in claim 15 wherein the layer translucent or transparent to solar radiation consists of mutually overlapping tiles.

17. A plurality of panels as claimed in claim 15 wherein the layer translucent or transparent to solar radiation consists of mutually overlapping glass slates or shingles.

18. A plurality of panels as claimed in any proceeding claim wherein an insulating layer is positioned behind the panels.

19. A plurality of panels as claimed in any proceeding claim wherein a membrane is positioned behind the panels.

20. A plurality of panels as claimed in claim 19 wherein the panels co-operate with the insulating layer to prevent solar radiation from reaching the membrane.

21. A plurality of panels as claimed in any proceeding claim wherein the panels mutually overlap so as to form a layer impermeable to precipitation.