Definition: Pilot plant
The construction and operation of a pilot plant is a part of R&D as long as the principal purposes are to obtain experience and to compile engineering and other data. But if, as soon as this experimental phase is over, a pilot plant switches to operating as a normal commercial production unit, the activity can no longer be considered R&D even though it may still be described as a "pilot plant".
Organisation for Economic Co-operation and Development (OECD), "Main Definitions and Conventions for the Measurement of Research and Experimental Development (R&D). A Summary of the Frascati Manual 1993", OECD, Paris, 1994, p.13