METHODS AND DEVICES FOR LARGE-SCALE SOLAR INSTALLATIONS
Methods and devices are provided for improved large-scale solar installations. In one embodiment, a junction-box free photovoltaic module is used comprising of a plurality of photovoltaic cells and a module support layer providing a mounting surface for the cells. The module has a first electrical lead extending outward from one of the photovoltaic cells, the lead coupled to an adjacent module without passing the lead through a central junction box. The module may have a second electrical lead extending outward from one of the photovoltaic cells, the lead coupled to another adjacent module without passing the lead through a central junction box. Without junction boxes, the module may use connectors along the edges of the modules which can substantially reduce the amount of wire or connector ribbon used for such connections.
1 . A photovoltaic module comprising:
a planar transparent module layer;
a planar module back layer; and
a plurality of photovoltaic cells between the module layer and the module back layer;
a first electrical lead extending outward from one of the photovoltaic cells into a first edge housing, the lead configured to be electrically coupled to an adjacent module without passing the lead through a central junction box, wherein the first edge housing extends over one surface and a side surface of the module back layer; and
a second electrical lead extending outward from another of the photovoltaic cells into a second edge housing, the lead configured to be electrically coupled to another adjacent module without passing the lead through a central junction box, wherein the second edge housing extends over one surface and a side surface of the module back layer;
wherein the first edge housing is located closer to one end of a long edge of the module and the second edge housing is located closer to an opposite end of the long edge of the module.
2 . A photovoltaic module comprising:
a planar transparent module layer;
a planar module back layer;
a plurality of photovoltaic cells between the module layer and the module back layer;
a plurality of solar cell interconnections;
a first electrical lead extending outward from one of the photovoltaic cells through a first opening in the module back layer into a first edge housing, the lead configured to be electrically coupled to an adjacent module without passing the lead through a central junction box; and
a second electrical lead extending outward from another of the photovoltaic cells through a second opening in the module back layer into a second edge housing, the lead configured to be electrically coupled to another adjacent module without passing the lead through a central junction box;
wherein the first edge housing is located closer to one end of a long edge of the module and the second edge housing is located closer to an opposite end of the long edge of the module.
3 . The module of claim 2 wherein the module is a frameless photovoltaic module without a frame surrounding a perimeter of the module.
4 . The module of claim 2 wherein the first electrical lead extends outward from the module through an opening in the module back layer.
5 . The module of claim 4 wherein the first electrical lead extends outward from the module through a non-central junction box.
6 . The module of claim 2 wherein the second electrical lead extends outward from the module through an opening in the module back layer.
7 . The module of claim 6 wherein the first electrical lead extends outward from the module through a non-central junction box.
8 . The module of claim 2 wherein the first electrical lead is a flat or round connector.
9 . The module of claim 2 wherein the second electrical lead is a flat or round connector.
10 . The module of claim 5 wherein the first or second connector has a length no more than about 2× a distance from one edge of the module to an edge of a closest adjacent module.
11 . The module of claim 6 wherein flat or round connector has a length no more than about 2× a distance from one edge of the module to an edge of a closest adjacent module.
12 . The module of claim 2 wherein the first electrical lead extends outward from an edge of the module layer along an outer perimeter of the module between module layers.
13 . The module of claim 2 wherein the second electrical lead extends outward from an edge of the module layer along an outer perimeter of the module between module layers.
14 . The module of claim 2 wherein the first electrical lead extends outward through an opening in the module back layer.
15 . The module of claim 2 wherein the first electrical lead extends outward from between the module layer and the module back layer through a moisture barrier.
16 . The module of claim 2 wherein the first electrical lead extends outward from between the module layer and the module back layer through a butyl rubber moisture barrier.
17 . The module of claim 2 wherein the first electrical lead extends outward through an opening in the module back layer, wherein a distance of the opening from the edge of the module is no more than about 2× a distance from one edge of the module to an edge of a closest adjacent module.
18 . The module of claim 2 wherein the second electrical lead extends outward through an opening in the module back layer.
19 . The module of claim 2 wherein the second electrical lead extends outward through an opening in the module back layer, wherein a distance of the opening from the edge of the module is no more than about 2× a distance from one edge of the module to an edge of a closest adjacent module.
20 . The module of claim 2 wherein the photovoltaic cell has a metallic underlayer.