Boiler

The two 3,500-hp steeple compound Unaflow steam engines powering the S.S. Badger represent one of the last types of reciprocating marine steam engines. Built by the Skinner Engine Company, most Unaflow engines are single expansion. These feature tandem high- and low-pressure cylinders separated by a common head. The Badger's four Foster-Wheeler Type D marine boilers, which supply 470-psig steam to the engines, are among the last coal-fired marine boilers built. 

Formerly known as the Oneida Street Power Plant, this plant served from 1918 to 1920 as the pilot plant in the United States for the development and use of finely pulverized coal firing in the boilers of steam-electric power plants. The results of the Oneida experiences were major changes in boiler design and lower costs of power generation. Following the early years of central station electric development, experiments at Onieda Street resolved persisting inefficiencies at a time when coal was increasingly expensive and of poorer quality.

The Ljungstrom air preheater is a regenerative heat exchanger, invented in the 1920s and soon used throughout the world. Dr. Fredrik Ljungstrom, then technical director at Aktiebolaget Ljunstrom Angturbin, invented it for preheating combustion air in boiler plants, but the use has expanded to include energy recovery in combination with the removal of oxides of sulfur and nitrogen.