A method of installing on a horizontal or near-horizontal support surface a solar panel array including multiple solar panels may include, at the deployment site, fabricating from metal coil stock longitudinally continuous rack channels each having upstanding legs of different heights, locating the channels in parallel rows with a spacing determined by a width of the solar panels with interior spaces of the channels facing upwardly, weighing the channels down on the support surface by placing ballast in the channel spaces, and positioning the solar panels each with an edge supported by a high leg of one channel of the channels and an opposite edge supported by a low leg of an adjacent channel of the channels.