U.S. patent application number 11/731363 was filed with the patent office on 2007-10-25 for solar array mounting system.
Invention is credited to Lachlan Bateman, Shay Brazier, Dan Gower Davies.
Application Number | 20070246039 11/731363 |
Document ID | / |
Family ID | 36425059 |
Filed Date | 2007-10-25 |
United States Patent
Application |
20070246039 |
Kind Code |
A1 |
Brazier; Shay ; et
al. |
October 25, 2007 |
Solar array mounting system
Abstract
A mounting stand for supporting a solar panel or other solar
energy collection device on a mounting surface, includes a body
including a stand-off element for supporting the body clear of the
surface, and a tension device, adapted to be connected between the
body and the mounting surface, so as to hold the stand-off element
securely in contact with the surface. The body preferably includes
a triangular space-frame made up of three parallel members one of
which has legs forming a stand-off elements while the other two
form a mounting for the solar energy collection device.
Inventors: |
Brazier; Shay; (Auckland,
NZ) ; Davies; Dan Gower; (Bath, GB) ; Bateman;
Lachlan; (London, GB) |
Correspondence
Address: |
FAY SHARPE LLP
1100 SUPERIOR AVENUE, SEVENTH FLOOR
CLEVELAND
OH
44114
US
|
Family ID: |
36425059 |
Appl. No.: |
11/731363 |
Filed: |
March 30, 2007 |
Current U.S.
Class: |
126/621 |
Current CPC
Class: |
F24S 25/13 20180501;
H02S 20/24 20141201; F24S 25/61 20180501; F24S 30/42 20180501; F24S
2025/6006 20180501; Y02E 10/50 20130101; F24S 2025/021 20180501;
F24S 2025/017 20180501; Y02E 10/47 20130101; Y02B 10/10 20130101;
Y02B 10/20 20130101; F24S 25/50 20180501 |
Class at
Publication: |
126/621 |
International
Class: |
E04D 13/18 20060101
E04D013/18 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 31, 2006 |
GB |
0606576.7 |
Claims
1. A method of mounting a solar energy collection system onto a
surface, comprising a) placing a support comprising a body
including stand-off means for supporting it clear of the surface in
a desired position; and b) connecting a tension member between the
body, and a point on the surface so that the stand-off means is
held securely in contact with the surface.
2. A mounting stand for supporting a solar panel or other solar
energy collection device on a mounting surface, comprising a body
including stand-off means for supporting the body clear of the
surface, and a tension device, adapted to be connected between the
body and the mounting surface, so as to hold the stand-off means
securely in contact with the surface.
3. A mounting stand according to claim 2 in which the tension
member comprises a resilient rod or cable.
4. A mounting stand according to claim 3 the lower end of the rod
or cable is connected to an anchorage point which is adapted to be
fixed to an underlying structure beneath the surface of a roof.
5. A mounting stand according to claim 4 in which the anchorage
comprises an upstanding portion which is adapted to extend through
the roof surface, having a fixing flange at its lower end.
6. A mounting stand according to claim 4 in which the upper end of
the anchorage comprises a mounting plate including a
weatherproofing flange of material adapted to be sealed to the roof
surface.
7. A mounting stand according to claim 2 in which the stand-off
means includes at least one leg having a foot member or members
extending away from the base of the leg or legs in different
directions across the surface.
8. A mounting stand according to claim 7 including a plurality of
plate-like or skid-shaped foot members.
9. A mounting stand according to claim 7 including a foot which
comprises a single ring-shaped member, whereby the anchorage point
can be arranged inside the ring.
10. A mounting stand according to claim 2 in which the body
comprises a triangular section space-frame forming a beam.
11. A mounting stand according to claim 10 in which the space-frame
comprises a primary elongate box-section or tube member and two
secondary elongate members which are arranged facing one another
and parallel to the primary member so as to form a
triangular-section beam, whereby a solar energy collection device
can be mounted between the secondary members, and the primary
member can then be mounted on a support surface.
12. A mounting stand according to claim 10 in which the beam is
provided with at least two pairs of legs spaced apart along its
length.
13. A mounting stand according to claim 12 further comprising a
tensioning member at or near each end.
14. A solar panel array mounted on a stand according to claim
2.
15. A solar panel array according to claim 14 further comprising an
inverter mounted on the stand and including power output rails
which are adapted to be connected in parallel with one or more
similar arrays.
16. A space-frame mounting for solar energy collection systems
comprising a primary elongate structural member and two secondary
elongate members which are all arranged parallel to one another and
connected together by arrangements of struts at suitable intervals,
so as to form a triangular-section beam, whereby a solar energy
collection device can be mounted on the secondary members and the
primary structural member can then be mounted on a support
surface.
17. A space-frame according to claim 16 in which the primary member
comprises a tube whereby the frame can be rotatably mounted on a
support.
18. A space-frame according to claim 16 in which the secondary
members are L-section or channel-section members.
19. A solar energy collection system mounted on a space-frame
according to claim 16.
20. A solar panel array mounted on a space-frame according to claim
16 and further comprising an inverter having power output rails
which are adapted to be connected in parallel with one or more
similar arrays.
Description
[0001] This invention relates to a method for mounting solar energy
collectors, such as photovoltaic arrays and solar thermal
collectors, onto building structures, and particularly, although
not exclusively, onto flat roof or low-pitch roof systems.
[0002] When mounting a solar panel array onto a flat roof, it is
desirable to provide a system which is quick to install, and avoids
the necessity for strengthening the building structure to take
additional loads. Preferably, it should be possible to install the
system without needing specialist lifting or handling equipment,
and without utilising special roofing methods, or compromising the
weather tightness of the roof.
[0003] Accordingly, the present invention provides a method of
mounting a solar energy collection system onto a surface,
comprising the steps of
[0004] a) placing a support comprising a body including stand-off
means for supporting it clear of the surface, in a desired
position: and
[0005] b) connecting a tension member between the body, and a point
on the surface so that the stand-off means is held securely in
contact with the surface.
[0006] The invention also extends to a mounting stand for
supporting a solar panel or other solar energy collection device on
a mounting surface, comprising a body including stand-off means for
supporting the body clear of the surface, and a tension device,
adapted to be connected between the body and the mounting surface,
so as to hold the stand-off means securely in contact with the
surface.
[0007] Preferably, the stand-off means comprises at least two legs
with enlarged pads or skid-shaped feet at their lower ends to
spread the load on the surface. The angle at which the legs are
attached to the body may be made adjustable, so that the
inclination of the body may be varied to accommodate different
latitudes and/or roof pitches.
[0008] Various other load-spreading geometries are also possible
for the stand-off means such as a foot comprising a ring which has
a relatively large diameter and a single leg extending upwardly at
an angle from one side of the ring, with its upper end connected to
the underside of the body. The tension device is then connected to
the surface, inside the ring, so that the leg forms a braced
cantilever. As a further alternative the ring can be replaced by a
pair of elongated splayed-apart feet extending from the base of the
leg.
[0009] Preferably, the tension device comprises a resilient rod or
cable made from a polymer or similar material that will not
transfer heat from a building exterior to the building
interior.
[0010] Preferably, where the mounting surface is weatherproofed,
for example on a flat roof, the tension device is arranged to
penetrate the surface, with suitable weatherproofing arrangements,
and is attached to a structural member or deck beneath the
surface.
[0011] Preferably, the tension device comprises two parts, the
first part comprising an anchoring means including a flange for
connection to the structural member or deck beneath the roof
surface, at its lower end, and an attachment means which extends
through the weatherproof membrane, at its upper end, and the second
part comprising a resilient rod or cable having connection means at
its lower end for connection to the upper end of the first member,
and a further connection means at its upper end, for connection to
the body of the mounting stand. Alternatively blind or self tapping
fixings can be used to pierce through the roof to the structural
member or deck, securing a mounting means that sits on the roof
which incorporates suitable waterproofing measures. A resilient rod
or cable that is connected to the mounting means and the body of
the mounting stand secures the frame to the mounting surface.
[0012] Preferably, the body of the stand comprises a light-weight
"space frame" construction, which may for example be made of
aluminium, and in a preferred embodiment the frame takes the form
of a triangular beam, comprising three elongate members which are
arranged parallel to one another and connected together by
arrangements of struts, at a spaced-apart intervals along the
length of the frame. Pairs of legs for contacting the support
surface are also attached to one of the members which forms the
main structural member, at suitable intervals, so as to provide
adequate support for the entire structure, when mounted on a
roof.
[0013] Preferably the beam comprises a main structural member, such
as a box-section or a tube, and a further pair of members which
form supports for the solar collection device. Thus the pair of
support members may be L-section or channel section members.
[0014] It will be appreciated that at least one tensioning member
is required, but when the stand is relatively long, there is
preferably one tensioning member near each end.
[0015] In one embodiment of the invention, the second and third
members are channel section members arranged with their open sides
facing one another, and at a spacing which is adapted to allow a
photovoltaic module or modules, or other solar energy collector, to
be mounted between them.
[0016] Some embodiments of the invention will now be described, by
way of example with reference to the accompanying drawings, in
which;
[0017] FIG. 1 is a schematic diagram of the mounting method of the
present invention;
[0018] FIG. 2 is a cross-section through a flat roof structure
illustrates a practical form of anchorage for the mounting system
of the present invention;
[0019] FIG. 3 is an exploded perspective view corresponding to FIG.
2;
[0020] FIG. 4 is a transverse cross-section through a mounting
device according to the invention;
[0021] FIG. 5 is an end elevation of a mounting system arranged
"in-situ" on a flat roof;
[0022] FIGS. 6a and 6b are perspective views of mounting frames
according to the invention;
[0023] FIGS. 7a-7c illustrate alternative stand geometries;
[0024] FIG. 8 is a cross-sectional view of an alternative example
of a mounting device according to the invention;
[0025] FIGS. 9a and 9b are cross-sectional views of an alternative
example of an anchorage for the mounting system of the present
invention; and
[0026] FIG. 10 is a cross-sectional view of a fixing arrangement
for the alternative anchorage of FIG. 9.
[0027] Referring firstly to FIG. 1, this illustrates the general
principle of the mounting method of the present invention in which
a structure indicated generally at 2 is required to be mounted on a
flat roof surface 4. It will be understood that such roof typically
comprises an underlying support structure 6, a layer of insulation
8, and a weatherproof covering 10.
[0028] In order to secure the structure 2 in a desired position, it
is preferable to avoid piercing the weatherproof covering 10, as
far as possible, or at least, reducing the number of such
perforations to a minimum. Accordingly, as illustrated, the
structure is supported clear of the surface by legs 12, each of
which terminates in a foot 14 comprising a compression pad. These
pads are formed with a relatively large area, so as to spread the
load on the roof.
[0029] In order to avoid multiple perforations in the roof, the
structure is secured in position by a tensioning member 16 which is
attached to an anchoring point 18 on the roof. In this way, the
number of fixings to the roof can be substantially reduced, and a
relatively large structure can be attached to a roof with just one
or two fixings (for example). It will be appreciated that the use
of such a small number of fixings with a conventional system could
result in damaging turning moments being applied to the roof.
[0030] FIG. 2 illustrates a suitable anchoring structure, which
comprises a tie rod 20 of suitable length to extend through the
insulation layer 8, mounted on a fixing plate 22 having fixing
holes 24 which enable it to be screwed or bolted onto a roof member
26 of the support structure 6, as illustrated more clearly in FIG.
3. The upper end the tie rod 22 is threaded for attachment to a
plate 28 carrying the anchorage 18, and a sealing member 30, which
may for example comprise a suitably shaped piece of roofing felt,
is attached to the top of the mounting plate 28.
[0031] It will be understood that the construction of flat roofs of
this kind is such that the insulation layer 8 is generally of a
standard thickness, and consequently, the tie rod 20 only needs to
made in a few different standard lengths, to enable the mounting
plate 28 to be mounted at a suitable level, just above the
waterproof membrane 10. Accordingly, the upper end of the rod 20
may be threaded into a blind hole 32 in the base of the mounting
plate 28, or, of course, there may be a hole passing right through
the plate 28, and the tension rod 20 may be attached by means of a
suitable nut, provided that any resultant joint can be suitably
sealed.
[0032] Referring to FIGS. 4 and 5, a practical example of a "space
frame" PV mounting system 36 is illustrated, in cross-section in
FIG. 4 which shows the frame alone i.e. the specific arrangement
for mounting a PV module or other solar energy collector, 38. As
can be seen from the drawing, this comprises a primary structural
member 40 which, in the example, is a fairly substantial box
section, and two channel section members 42 and 44 which are
arranged facing one another, and extending parallel to the primary
box section 40. All three members are interconnected by a
triangulated space frame, an example of which is shown in the
perspective view of FIGS. 6a and 6b, and it will be appreciated
that this arrangement provides a very high strength-to-weight
ratio. In addition, it enables the mounting angle of the solar
energy collector 38 to be preset for its location, by suitably
dimensioning the interconnecting struts 46 and 48 forming the sides
of the triangle, so that when the primary box section structural
member 40 is mounted horizontally, the orientation of the frame
will automatically be suitable for the latitude of the
installation.
[0033] It will be appreciated that the frame may also be made up of
members of various different cross-sections, depending on the
application. For example the main structural member may be a tube
which is rotatably mounted in a collar on the support system so
that the frame can be set at different angles. The secondary
members, on which the actual solar collection device is mounted,
may also be of other cross-sections such as L-shaped or simply flat
strips so as to allow a variety of different fixing methods to be
employed. The spacing between the members can also be varied to
allow for different size panels or different fixing methods. The
frame may also be made in various different widths and lengths. For
example, the frame shown in FIG. 6b is approximately 6 metres in
length.
[0034] As illustrated in FIG. 5, outwardly extending legs 50, 52
are attached to the primary structural member 40 at intervals along
its length, and are terminated at their lower ends with pads 54,
56, which in turn rest on the upper surface of a flat roof 4. A
mounting eye 58 is fixed on the underneath surface of the member
40, and is connected to an anchorage 18 on the roof, by means of a
tension member 60 which can for example be a polymer cable. The
interconnection between the anchorage point 18, and the roof,
corresponds to that described above with reference to FIGS. 2 and
3, and accordingly, will not be described in detail here.
[0035] It will be appreciated that dependent upon the length of the
solar array, the support frame may be relatively long, as shown in
FIGS. 6a and 6b. If that is the case, it will be preferable to
provide two anchorage points 18, spaced-apart towards the end of
the structure, in order to stabilise it properly against possible
movement under the influence of weather, for example. Where a
smaller frame design is used, a single fixing point can be situated
in the centre of the frame, with multiple frames mechanically
joined by, for example, a flange, to prevent rotation of the
frames. It will be appreciated that this enables a relatively large
structure to be fixed firmly into position, without the need for a
large number of fixings, or the addition of unwieldy ballast to
hold it in the desired position.
[0036] The mounting system of the invention also lends itself well
to multiple modular PV installations or installations which can
easily be upgraded by adding another similar module. For this
purpose each module may be equipped with a built-in inverter, for
example a "string inverter" set up for its respective solar array,
so that additional arrays can simply be connected in parallel with
one another.
[0037] Alternatively a number of frames may be connected to a
central inverter. In this case each frame would be designed such
that it matched the electrical requirements of the inverter. For
example a 300 kW inverter might require 25 parallel strings of 24
PV modules attached in series. A frame in this case could have 8,
12, or 24 modules, meaning that 3, 2 or just one frame would be
required to create a string. This would simplify the design of the
electrical connections.
[0038] FIGS. 7a-7c illustrate some diagrammatic examples of further
possible stand-off mounting arrangements which are relatively
self-explanatory, the main parts being referenced similarly to
those in FIG. 1. As will be clear from the drawings, although it is
desirable to have at least two legs (FIG. 7a) with suitable
skid-shaped feet 14 it is also feasible to utilise a "braced
cantilever" geometry in which there is only one stiff leg (FIGS. 7b
and 7c) and the spaced-apart foot portions extend away from it in
the form of a single ring (7b) or two splayed apart feet (7c). Both
of these arrangements provide suitable spaced-apart foot portions
so that the anchorage (18) on the roof surface can be suitably
arranged between them to tension the stand against the surface.
[0039] FIG. 8 shows another example of a PV mounting system 36 in
which one of the channel section members 42,44 (FIG. 4) is replaced
by a clamping arrangement comprising first and second folded sheets
62, 64. The folded sheets 62, 64 are arranged such that the PV
module or other solar energy collector 38 can be securely clamped
therebetween. The folded sheets 62, 64 extend parallel to the
primary box section 40 (FIG. 4). The folded sheets are clamped
together by way of a nut 66 and a corresponding bolt 68 which
extends through a slot 70 in one of the folded sheets 62, 64. The
sheets 62, 64 may be made from aluminium. Although only one
clamping arrangement 62, 64 is shown in FIG. 8, it will be
appreciated that both of the channel section members 42, 44 could
be replaced therewith.
[0040] Referring to FIGS. 9a and 9b, an alternative example of an
anchorage 72 for securing the structure (not shown) to the roof
structure or member 26 is shown. The anchorage 72, which includes a
mount, is secured to the roof member 26 by means of screws 74 or
roofers' fixings of a suitable length which pass through an
intermediate, or sandwiched, panel 76. The intermediate panel 76,
preferably comprises a composite panel roof deck. A suitable
sealing method, for instance butyl tape, silicon, washers or
gaskets, 78 may be provided between the head 80 of the screws 74
and an upper surface of the panel 76. In this way, the anchorage 72
comprises a plate that sits on a roof 76 and is fixed to the
structural member 26 below the roof without compromising the
weather tightness of the roof. In the case of a membrane roof, the
anchorage may be compressible so that, if stood upon, tearing of
the membrane can be prevented.
[0041] Referring to FIG. 10, a fixing arrangement 82 for securing
the anchorage 72 to the roof member 26 is shown. In addition to the
intermediate panel 76 being secured to the structural member 26
indirectly by way of the screws 74, additional screws 84 may be
provided so as to fix the panel 76 directly to the structural
member 26.
* * * * *