Definition and Analysis of Modularity Degree of Nuclear Power Plant Construction

Modular Construction, as a significant feature of AP1000 Nuclear Power Plant (NPP) technology, has currently become one of the major directions of the technological development of most NPP construction worldwide. Based on data of composition, quantity, cost of various structural and mechanical modules in the Nuclear Island of NPP, this paper researches into the history of NPP construction’s development toward the modular mode, and into previous practices of NPP construction, especially the practice of AP1000 NPP in China under construction; analyzes the pertinence and the degree of influence among the key elements; and brings up with the fundamental definition of “Modularity Degree” for NPP construction. Further, with the definition proposed, the paper, considering the NPP Nuclear Island Construction as the object, aims to build a relation model and evaluation index for “Modularity Degree”, project cost and construction duration.