Modular solar generating system

A modular solar generating system is disclosed. The system includes a plurality of self-contained solar modules which are interconnectedly disposed in an array about the perimeter of a rigid framework housing a sign, light, or other load means necessitating electrical power during the night time hours. The modules themselves consist of a photovoltaic plate sandwiched between two suitable cover plates, including in this arrangement one or more continuous conductors. The modules are linked together by way of male and female plug connectors whereby the array may then be electrically connected to a battery. When the modular system is arranged in this fashion and exposed to incident sunlight for an appropriate period of time, power may be provided to a sign, light or other electrical apparatus for nighttime use.

BACKGROUND 
The present invention relates generally to a modular solar generating 
system for use in providing power to illuminated outdoor signs. More 
particularly, this invention relates to an illuminated outdoor sign 
comprised of a rigid upright frame about which a plurality of solar 
modules are interconnectedly disposed. These modules are linked to a 
battery whereby electricity produced by the solar modules is stored for 
nighttime use in a lighting element of the sign or in some other fashion 
where electric power is required. 
Illuminated signs, billboards and warning signals are a common sight in 
both cities and along the sides of highways or major roads. While 
illuminated signs or signals constitute an effective advertising medium 
during nighttime hours, a variety of factors can reduce or eliminate the 
economic feasibility of supplying electricity to these signs. Such factors 
might include the remoteness of a given location from available power 
supplies or the expense of providing such electric power. 
For these reasons, various attempts have been made to develop solar powered 
generating systems which would transform the sun's energy into electricity 
which could be stored in batteries. This electricity may be later directed 
to provide electric power to an illuminated sign or other electrically 
dependent device during the nighttime hours. 
Many such attempts to produce a solar powered sign or signal have resulted 
in systems whereby solar panels have been remotely or incidentally 
attached to the sign or signal itself. This arrangement, however, has 
required a separate means for mounting the solar panels in a position 
above or proximate to the sign. The result has added complexity in the 
construction of the sign as well as greater exposure of the solar panel 
structure to adverse weather conditions. The placement of panels above or 
proximate to the signs has served to advertise the existence and identity 
of the solar panels, resulting in increased theft and vandalism. 
SUMMARY OF THE INVENTION 
The present invention overcomes many of the disadvantages of prior art sign 
or signal systems employing solar technology. 
The present invention relates generally to the use of photovoltaic cells to 
power a recharge system for replenishing one or more slow discharge 
batteries, which may then be used at selected times to power a variety of 
systems including illuminated signs. This new system may be used, for 
example, in providing battery power to signs, post and panel directional 
signals, security systems, as well as a variety of conventional and new 
lighting systems. 
More particular aspects of the invention include solar modules mounted 
about the periphery of a sign or other electrical component structure and 
are integrated in the outer facing of the structure by specially designed 
low profile channels. These channels form the outer edges of the sign or 
other structure and hold the solar modules securely in place. A specially 
designed top or cap channel is fitted with solar modules and then bridged 
along the top or side of the sign in order to complete the circuit. 
The solar module array is electrically connected to one or more energy 
storing devices which may be placed either within or below the structural 
framework of a given electrical component. In particular embodiments of 
the invention, the solar modules may be linked in series or parallel or in 
combinations thereof. In one embodiment of the invention, a voltage 
regulator is wired between the solar module array and the battery. 
The battery is wired to an illumination means of the sign or other desired 
electrical load. In one embodiment of the invention, a timer or controller 
is wired between the electrical load and the battery. In another 
embodiment of the invention, a photoelectric eye may be wired to this 
timer in a manner to actuate the electrical load at a particular time or 
under particular lighting conditions. 
Thus, the adjustable timer/controller means may allow the sign to be "on" 
for a desired length of time. It may also monitor the battery charge 
level, and automatically turn the sign or other load off if the batteries 
are low. 
The solar module, itself, is composed of a thin film photovoltaic plate or 
other photovoltaic material which is sandwiched between a transparent 
cover plate and a rigid back plate. One or more continuous conductor wires 
are cast into this back plate. An electrical connection between the 
continuous conductor(s) and the solar panels may be provided through a 
spring or other conductive means positioned between the positive or 
negative side of the photovoltaic panel and the continuous conductor. This 
configuration is designed to prevent the solar modules from being 
assembled improperly. The conductors can be placed to permit the panels to 
be connected in parallel or in series. 
In one embodiment of the device, a diode is wired to a positive conductor 
of each module. In one embodiment sub-array of blocking diodes 
electrically separate the respective sides of the sign preventing 
inadvertent power losses because different sides of a sign or structure 
will normally receive different amounts of sunlight during the course of 
each day. Thus if one side of the sign or structure is occasionally 
shaded, it will not dissipate energy from the panels on the other sides 
which are exposed to sunlight. The integration of a diode into each solar 
module also serves to prevent power loss due to damage or shading to one 
or more of the modules in the module array. 
In yet another embodiment of the device, a laminate material is interposed 
between the thin film photovoltaic plate and the cover and back plates. 
The addition of this laminate material serves to moderate any detrimental 
expansion differential between the exterior plate material and the 
material comprising the inner photovoltaic plate. 
The modular solar generating system described has many advantages over the 
prior art. The present system is completely self-contained, will 
automatically turn on and off, and requires no external power source or 
control. Additionally, the system is comprised of energy producing 
photovoltaic solar modules which form an integral yet inconspicuous 
structural component of the system. Thus simplifies set up of the 
structure while greatly reducing the incidence of vandalism and theft of 
the modules themselves. Integration of the modules in this fashion also 
serves to aesthetically improve the appearance of the sign or structure 
over similar structures described in the prior art. 
The present system eliminates the need for costly electrical hookup during 
installation, and in many cases, can be installed less expensively than 
conventional power systems. It also allows for flexibility of movement 
without the danger of disturbing or interfering with underground 
utilities, such as phone cables and sprinkler systems. The system 
conserves energy and reduces utility cost because it is completely solar 
powered. However, it may also be backed up by conventional electric 
service or as a back up to conventional electric service. The system can 
also provide power to systems that would otherwise be inoperative during 
interruptions in electrical service. 
The design of the photovoltaic modules themselves also demonstrates 
advantages over the prior art. First, each module is comprised of a plug 
means that eliminates the need for a separate wiring of the modules. By 
eliminating the external wiring required to interconnect the solar panels, 
system reliability is improved and costly manufacturing steps are 
eliminated. The present invention also affords greater design flexibility 
with few dimensional constraints. 
Each module is comprised of male and female coupling means which may be 
quickly attached or detached depending on any given application. The 
design of the present solar module enables rapid and simple modification 
of the solar collecting surface area by the addition or deletion of 
modules from the system. 
Another feature of this design is the structural strength imparted to the 
module by the incorporation of the continuous plug connectors. Two or more 
continuous connector wires are encapsulated into the module body, forming 
the male and female ends of the plug connectors. This arrangement imparts 
additional strength and rigidity to the module, reducing damage due to 
flexing during manufacturing, transportation, service and use. Thus, the 
electrical connector comprises a structural component as well as an 
electrical conductor and connector.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION 
FIG. 1 generally illustrates the component parts of the modular solar 
generating system 12. In one embodiment of the present invention, solar 
modules 10 are interconnectedly disposed in a module array about the 
periphery of a rigid frame 2. Frame 2 comprises one or more legs 3 for 
supporting the frame 2 above the mounting surface 4. A battery 5 
(including but not limited to deep cycle gel cell batteries) is 
electrically connected by a power line 6 to the solar module array. The 
power line 6 may run in the interior of one or more of the legs 3 as 
shown. The battery 5 may be buried or recessed beneath the mounting 
surface to hide it from view and to protect it from the elements. A cover 
(not shown) may be required to service the battery 5 and keep rain and 
other moisture out of the recess housing the battery 5. Also linked to the 
battery 5 is a lighting means 8. In one embodiment of the device, a 
regulator 7 is linked between the solar module array 1 and the battery 5. 
A translucent face plate 9 is disposed within the frame 2 and may include 
thereon lettering, messages, logos, or the like that form the subject of 
the display. 
FIG. 2 illustrates the component parts of another embodiment of the present 
invention. In this embodiment, a plurality of solar modules 10 are 
interconnectedly disposed about the perimeter of the sign system 12. This 
drawing illustrates the positioning of the continuous conductors 13 in the 
modules 10. At the top corners of the frame 2 where the solar modules 10 
abut, a corner connector piece 14 is positioned to form an electrical 
connection between the modules lining the top and the sides of the sign 
system 12. Also in this embodiment of the present invention, a battery 5 
is positioned on a removable tray 16 slidably mounted on the base of the 
sign frame 2. An insulating material 17, such as foam or other suitable 
material, may be incorporated into the outer structural panels 18 forming 
the base of the sign system 12. In this embodiment also, a reflective 
surface 20 is disposed within the sign frame 2 to maximize the 
illumination of the lighting means 8. A translucent face plate 9 is fitted 
within the frame 2 and may include lettering, messages, logos, etc., that 
form the subject of the display. 
FIG. 3A illustrates in detail the way in which the solar modules 10 are 
connected. Modules 10(a) and (b) disposed in the same plane are connected 
by plugging the male end 16 of leads 13 of module 10(a) into the female 
end 17 and of module 10(b). Modules 10(a) and (c) are disposed in 
different planes. Modules 10(a) and (c) are connected by a connector 14. 
The male ends 16 of the connector 14 are plugged into female ends of 
module 10(a). The male ends 16 of module 10(c) are plugged into the female 
ends 17 of the connector 14. 
A battery connector piece 29 is attached to a module 10(d) by the plug 
connectors 16 and 17. Electrical leads 6 from the connector 29 run to the 
battery (not shown). 
Referring to FIGS. 3A, 3B, and 3C, threaded connectors 21 disposed normal 
to the plane of the modular array are attached to the bottom of the 
channel 22 in which the modules are slidably mounted. The connectors 21 
make it possible to anchor the modular array to the structure framework 24 
by means of wing nuts 25 or other suitable fastening means. 
Referring in particular to FIGS. 3B and 3C, the channel 22 may be attached 
to the frame 2 or legs 3. In an alternate embodiment, the frame 2 and legs 
3 may be so designed as to define the channel 22. This feature reduces the 
number of components necessary for the construction of the system 12. In 
this fashion, the solar modules themselves would form at least one 
supporting face of the frame 2 and leg members 3. 
FIG. 4 generally illustrates an electrical schematic for the embodiments of 
FIGS. 1-3 and includes the modules 10 of the solar array. The battery 5 is 
electrically connected to the array combination. In some applications, it 
may be desirable to connect a voltage regulator 26 to the circuit between 
the solar array and the battery 5. A timer/controller 28 may be wired in 
the circuit between the battery 5 and the load 40. Various timers may be 
used including but not limited to multiple stage timers. It may also be 
desirable to wire a photoelectric eye 32 to the timer 28. In some 
applications it may be advantageous to shield the photoelectric eye 32. 
In a preferred embodiment of the present invention, it is desirable to 
insert a diode 34 in the circuit of each solar module 10 as shown. The 
diode 34 to the positive lead is selected to prevent undesired flow of 
current from those areas illuminated by sunlight to those areas not so 
illuminated. The placement of the diode also prevents leakage from power 
producing modules to a damaged module, and also prevents power leakage 
from the battery 5 to the module 10 at night. 
FIGS. 5A and 5B illustrate in an exploded view the component parts of each 
solar module 10. In one embodiment, a thin film photovoltaic plate 50 is 
sandwiched between a transparent cover sheet 51 and a rigid back sheet 52. 
The cover sheet 51 may be made of such transparent materials as glass, 
LEXAN, TEDLAR, urethane or acrylic polymers, etc. The back sheet 52 may be 
comprised of such materials as steel, glass, acrylic or urethane polymers, 
etc., to provide additional structural rigidity to the solar module 10. 
Continuous, parallel conductors 13 are aligned with or disposed within the 
bottom sheet 52 and are connected to the photovoltaic plate 50 by a 
suitable connector means 54. In some applications, a diode 34 may be wired 
between the positive conductor 13 and the photovoltaic plate 50. In other 
applications, it may be necessary to insert a suitable laminate material 
56 such as silicone, between the top plate 51 and the back plate 52 as to 
moderate undesired differences in expansion rates between the photovoltaic 
plate 50 and the top and back plates 51 and 52. In other applications, it 
may be desirable to encapsulate the entire module including the 
photovoltaic plate 50, the top and back plates 51 and 52 and the 
continuous conductors 13, in a transparent material such as acrylic, 
urethane, silicone, TEDLAR, LEXAN, etc. as to better insulate the module 
components from adverse conditions as well as providing additional 
rigidity to the modules themselves.