A frame for supporting a photovoltaic module (PV) includes a plurality of sidewalls, which are arranged to support the PV module at a spaced distance from an installation surface. The sidewalls define an interior volume having an open top and open bottom. One sidewall has a plurality of openings defined therethrough along a portion of a length thereof. A plenum is disposed adjacent to an exterior surface of the first sidewall and extends along at least the portion of the length of the first sidewall having the plurality of openings defined therethrough. The plenum has an inlet port for receiving a flow of warmed air from a source of warmed air, and is configured to distribute the flow of warmed air through at least some of the plurality of openings in the first sidewall and into the interior volume.