The Plains End Power Station located in Colorado, USA, is one of the largest power plants with reciprocating engines as prime movers. In two units of this power plant there are totally 34 engine-generator sets driven by Wartsila reciprocating engines. Total installed capacity of the plant is ca. 230 MW. Plains End Power Station serves a source of peakload power and grid-stability plant, which is particularly important in an area with high wind power capacity. Features of the used engines like their high operational flexibility and very short start-up time, combined with the layout of multiple parallel gensets of relatively small outputs, greatly facilitates this type of operations, allowing to quickly and reliably supply amount of power currently needed for grid balancing. The paper presents operational experience and specific operational conditions of a peakload and grid-stability plant using gas reciprocating engines.