A power plant and method for harnessing power from a source of working fluid. The power plant may include a power shaft that includes a first power gear, a first reciprocating engine situated proximate to the power shaft and connected to the first power gear for delivering a power stroke. The first reciprocating engine may include a first bucket assembly which comprises a first bucket mounting frame, a first bucket, and a first connecting mechanism that connects the first bucket to the first bucket mounting frame to form a first hinge that pivots about a first pivot axis such that the first bucket creates a turning moment about the first pivot axis, and a first locking mechanism for selectively locking the first bucket in the first bucket mounting frame.