The majority of the images in this collection come from the Delmarva Power and Light Company (DP&L), a predecessor of Conectiv, Inc. The images can generally be divided into three categories: DP&L equipment and facilities, DP&L employees, and views of buildings, both commercial and residential, throughout northern Delaware. DP&L facilities pictured include power plants at Edgemoor, Delaware City, and along the Indian River in Delaware. There are also a series of photographs of nuclear plants in Vienna, Maryland and Salem, New Jersey. Exterior and interior views of DP&L offices in Wilmington include photographs of the sales floor at the 600 Market Street office and three decades-worth of window displays advertising electric appliances and heating systems. Images of the DP&L office building at 800 King Street include its construction, the move from 600 Market Street, and the building's dedication. Smaller DP&L offices and substations throughout the state are also featured. Finally, electrical equipment, power lines, towers and wiring are featured in a number of photographs.

DP&L employees are featured in many of the above photographs, particularly in images of construction and the installation of power lines and equipment. Employee safety classes and training sessions are also featured. Candid images of employee leisure activities include company picnics and images from Quarter Century Club banquets. Most of the employee photographs in this collection, however, are posed individual or group portraits, a significant portion of which are identified.

The remaining portion of the collection is comprised of images of buildings throughout northern Delaware. These include structures in downtown Wilmington, especially buildings along Market Street and in the area of Rodney Square. The Grand Opera House is featured in a number of images, both before and after its restoration. Aerial images of the city are also included, many of which were taken before the Interstate 95 construction. Numerous commercial, industrial and residential areas outside of Wilmington, which were served by DP&L electricity, are also featured in the collection. These photographs include aerial views of Prices Corner, Merchandise Mart, and the Tri-State Mall, as well as street views of other stores around Wilmington. Industries served by DP&L include the Diamond Shamrock Chemical Company, Atlas Chemical Industries, General Motors and the Phoenix Steel Corporation. A selection of historical materials, including corporate timelines, newsletters and company press releases round out the collection.