A powership (or power ship) is a special purpose ship, on which a power plant is installed to serve as a power generation resource.

Converted from existing ships, powerships are self-propelled, ready to go infrastructure for developing countries that plug into national grids where required.[1] Unmotorised powerships, known as power barges, are power plants installed on a deck barge. These are sometimes called floating power plants or barge mounted power plants. They were initially developed during World War II by General Electric for the War Production Board as a transportable large-scale power generation resource.

Powerships or power barges can be equipped with single or multiple gas turbines, reciprocating diesel and gas engines, boilers or nuclear reactors for electricity generation. Bureau Veritas, an international certification agency with experience in overseeing both shipbuilding and power plant development, classifies such floating power plants as "special service power plants