Roof integrated photovoltaic system with improved serviceability
A roof integrated photovoltaic mounting system includes a plurality of aluminum rails mountable in horizontal spaced relationship on a roof for receiving courses of photovoltaic panels or photovoltaic tiles. The PV panels or tiles have an extruded attachment feature along their forward edge portions that defines a downwardly projecting forwardly facing hook. Panels or tiles are installed by placing each panel or tile on a pair of rails and sliding the panel or tile down until its forward facing hook engages beneath a rear facing tongue on a rail below. A PV panel or tile in a next lower course is installed by slipping its rear edge beneath the forward edge of a panel or tile in a next higher course. The panel is then hinged down about its rear edge until its forward edge portion engages a support rail below. The panel is then slid down until the hook of its attachment fixture engages beneath the tongue of the downslope rail. When the entire array is installed in this manner, the forward edges of the panels are held down by the hook and tongue engagements and the rear edges are held down by being underneath the forward edges of panels in a next higher course. The procedure is reversed to remove a panel for servicing or replacement. In the case of solar glass tiles, water troughs are installed on the rails underlying abutting ends of tiles in a course to collect rainwater and direct it onto the upper surface of a tile in a next lower course.
1. A roof integrated photovoltaic system comprising:
a plurality of support rails mountable on a roof deck in spaced apart relationship with each rail extending substantially horizontally across the roof deck;
an upslope facing edge of each support rail having at least one first engagement feature;
a plurality of photovoltaic panels each having an upslope edge, a downslope edge, a right side edge, a left side edge, an upper surface for exposure to sunlight, and an underside;
the plurality of photovoltaic panels being installable on the plurality of support rails in courses with the downslope edges of photovoltaic panels in one course overlapping the upslope edges of photovoltaic panels in a next lower course and with the left side edge of each photovoltaic panel in a course abutting the right side edge of an adjacent panel in the course;
wherein the photovoltaic panels of one course are staggered with respect to photovoltaic panels in the next lower course;
a structure extending along the underside of each photovoltaic panel adjacent the downslope edge thereof;
at least one second engagement feature on the structure, the at least one second engagement feature configured to interlock with the first engagement feature of a downslope support rail when a photovoltaic panel is positioned on an upslope support rail and a downslope support rail and slid in a downslope direction;
wherein the first engagement feature comprises a upslope facing tongue and the at least one second engagement feature comprises a downslope facing hook configured to move beneath and thereby interlock with the upslope facing tongue; and
water troughs positioned beneath the abutting side edges of each pair of photovoltaic panels;
wherein each water trough configured to: (i) collect water that seeps between the abutting side edges of each pair of photovoltaic panels and (ii) direct the water onto a top surface of a photovoltaic panel in the next lower course;
whereby the downslope edge of each photovoltaic panel in one course is secured to the downslope rail on which it rests and the upslope edge of each panel is secured by the overlapping downslope edges of photovoltaic panels in a next higher course.
2. A roof integrated photovoltaic system as claimed in claim 1 wherein the support rails are formed of extruded aluminum.
3. A roof integrated photovoltaic system as claimed in claim 2 wherein the at least one engagement feature is part of the extruded aluminum support rails.
4. A roof integrated photovoltaic system as claimed in claim 1 further comprising brackets mountable to a deck of the roof, the plurality of support rails being mounted to the brackets.
5. A roof integrated photovoltaic system as claimed in claim 4 wherein the support rails are adjustably mountable to the brackets so that the support rails can be leveled.
6. A roof integrated photovoltaic system as claimed in claim 1 further comprising a water management trough extending beneath the abutting edges of adjacent photovoltaic panels, the left side edge and the right side edge of the photovoltaic panels comprising flashing that extends into the water management trough.
7. A roof integrated photovoltaic system as claimed in claim 1 wherein the structure extending along the underside of each photovoltaic panel comprises a frame member attached to the downslope edge of the photovoltaic panel, the frame member being profiled to define the structure extending along the underside of each photovoltaic panel.
8. A roof integrated photovoltaic system as claimed in claim 1 wherein the structure extending along the underside of each photovoltaic panel is adhered to the underside of each panel with adhesive.