System for retrofitting energy supply modules in the region of a traffic route, which traffic route has along both longitudinal sides a multiplicity of support masts, whereby the system: has a multiplicity of transverse supporting cables (11, 14), which are extendable over the traffic route, transversely to the traffic route, between opposite support masts, and has a multiplicity of solar panels (20, 21), which are mountable on the transverse supporting cables (11, 14) over the traffic route, characterized in that, for each support mast of the multiplicity of support masts, the system: has at least one elongated attachment element, which is mountable on each of the said support masts, and which reinforces the stiffness of each of the said support masts over a majority of the length of each of the said support masts; has at least one first diversion element, which is attachable on an upper region of each of the said support masts, and by means of which one of the said transverse supporting cables is able to be diverted from its transverse orientation to a substantially vertical orientation; has at least one fixing element which is attachable on a lower region (4, 5, 6) of each of the said support masts, and by means of which a substantially vertically oriented supporting cable (11, 14) is able to be anchored in a tensioned way on the said lower region (4, 5, 6); whereby the forces which are exerted by the solar panels (20, 21) on the said transverse supporting cable (11, 14) are conducted through the transverse supporting cable via the at least one first diversion element and into the lower region (4, 5, 6) of each of the said support masts. has a multiplicity of transverse supporting cables (11, 14), which are extendable over the traffic route, transversely to the traffic route, between opposite support masts, and has a multiplicity of solar panels (20, 21), which are mountable on the transverse supporting cables (11, 14) over the traffic route, characterized in that, for each support mast of the multiplicity of support masts, the system: has at least one elongated attachment element, which is mountable on each of the said support masts, and which reinforces the stiffness of each of the said support masts over a majority of the length of each of the said support masts; has at least one first diversion element, which is attachable on an upper region of each of the said support masts, and by means of which one of the said transverse supporting cables is able to be diverted from its transverse orientation to a substantially vertical orientation; has at least one fixing element which is attachable on a lower region (4, 5, 6) of each of the said support masts, and by means of which a substantially vertically oriented supporting cable (11, 14) is able to be anchored in a tensioned way on the said lower region (4, 5, 6); whereby the forces which are exerted by the solar panels (20, 21) on the said transverse supporting cable (11, 14) are conducted through the transverse supporting cable via the at least one first diversion element and into the lower region (4, 5, 6) of each of the said support masts. has at least one elongated attachment element, which is mountable on each of the said support masts, and which reinforces the stiffness of each of the said support masts over a majority of the length of each of the said support masts; has at least one first diversion element, which is attachable on an upper region of each of the said support masts, and by means of which one of the said transverse supporting cables is able to be diverted from its transverse orientation to a substantially vertical orientation; has at least one fixing element which is attachable on a lower region (4, 5, 6) of each of the said support masts, and by means of which a substantially vertically oriented supporting cable (11, 14) is able to be anchored in a tensioned way on the said lower region (4, 5, 6); whereby the forces which are exerted by the solar panels (20, 21) on the said transverse supporting cable (11, 14) are conducted through the transverse supporting cable via the at least one first diversion element and into the lower region (4, 5, 6) of each of the said support masts.