Any electrical service utility vehicle owned and operated by a public utility, as defined in § 56-265.1, and having a gross vehicle weight rating greater than 15,000 pounds may be equipped with clear auxiliary lights that shall be mounted on the lower portion of the vehicle and aimed downward for the exclusive use of ground lighting. Such lights shall be of a type approved by the Superintendent and shall not be used in a manner that may blind or interfere with the vision of the drivers of approaching vehicles. In no event shall such lights be lighted while the vehicle is in motion.