Photovoltaic system, having - a plurality of bifacial PV modules that are arranged upright on a supporting structure, - wherein the supporting structure has several posts that are attached, in particular anchored, to or in the ground, - wherein crossbars are attached to the posts, which crossbars connect two neighboring posts to one another in each case, - wherein two posts and two crossbars in each case define a substantially rectangular mounting field, in which at least one PV module is arranged, - wherein the posts are configured in the form of longitudinal profiles, - wherein the posts are divided into at least one fastening section connected to the ground and a holding section connected thereto and extending above the fastening section, and - wherein holding surfaces are formed on the posts, to which holding surfaces an associated crossbar can be attached over a large area, characterized - in that the crossbars are narrower than the posts and are arranged centrally with respect to the posts, - in that the holding surfaces - are formed as flanges on one of the longitudinal profiles, wherein the respective flange extends along the entire holding section of the post and is part of the longitudinal profile and/or - are formed as tabs on respective openings of the longitudinal profiles, wherein the respective shape of a tab is predetermined by the shape of the associated opening in the respective longitudinal profile, and - in that the flanges and also the tabs extend in a direction and laterally offset to a plane that is formed by the PV modules and - in that respective outer edges of the respective post, which extend in the longitudinal direction of the post, are spaced further from the said plane of the PV modules than the respective flange or the respective tab. - a plurality of bifacial PV modules that are arranged upright on a supporting structure, - wherein the supporting structure has several posts that are attached, in particular anchored, to or in the ground, - wherein crossbars are attached to the posts, which crossbars connect two neighboring posts to one another in each case, - wherein two posts and two crossbars in each case define a substantially rectangular mounting field, in which at least one PV module is arranged, - wherein the posts are configured in the form of longitudinal profiles, - wherein the posts are divided into at least one fastening section connected to the ground and a holding section connected thereto and extending above the fastening section, and - wherein holding surfaces are formed on the posts, to which holding surfaces an associated crossbar can be attached over a large area, characterized - in that the crossbars are narrower than the posts and are arranged centrally with respect to the posts, - in that the holding surfaces - are formed as flanges on one of the longitudinal profiles, wherein the respective flange extends along the entire holding section of the post and is part of the longitudinal profile and/or - are formed as tabs on respective openings of the longitudinal profiles, wherein the respective shape of a tab is predetermined by the shape of the associated opening in the respective longitudinal profile, and - are formed as flanges on one of the longitudinal profiles, wherein the respective flange extends along the entire holding section of the post and is part of the longitudinal profile and/or - are formed as tabs on respective openings of the longitudinal profiles, wherein the respective shape of a tab is predetermined by the shape of the associated opening in the respective longitudinal profile, and - in that the flanges and also the tabs extend in a direction and laterally offset to a plane that is formed by the PV modules and - in that respective outer edges of the respective post, which extend in the longitudinal direction of the post, are spaced further from the said plane of the PV modules than the respective flange or the respective tab.