The Holtwood Steam Plant Design and Operation in Coordination With Water Power

The Holtwood Steam Plant is located in Lancaster County, Pa., on the Susquehanna River, about 24 miles above tide-water, adjacent to and closely coordinated with the 111,000-kw. hydro-electric plant of the Pennsylvania Water & Power Company, and through the latter company´s customers, it is a part of a hydro-steam system including Baltimore, Md., and Lancaster, York, and Coates-ville, Pa., with a total installed generator capacity of about 370,000 kw. and with high-tension connections to two other large systems. It is a pulverized fuel burning station, containing at present two 10,000-kw. generators and three l400-hp. boilers. The plant is laid out for an ultimate capacity of at least 120,000 kw. The station went into operation in July 1925. The paper gives the reasons for building a steam plant at Holtwood, some of them being general advantages in such a location for a plant, which is supplementary to a run-of-river hydroelectric plant, and others being the particular advantage, in this instance. In general, during the low-flow period, the steam plant carries the base load or belt generation, and during high flow, when the hydroelectric plant is operated at maximum capacity whenever the load permits, the steam plant carries the peaks. This station was especially planned to suit such conditions of operation and was designed for mechanical sturdiness, reliability of service, quick starting, ability to float in at no load, and for maximum coordination with the hydroelectric plant rather than for maximum economy or minimum first cost.