September 2

have sprung to life in these recent years at the welcome sight of a possible nuclear power renaissance, IRIS (International Reactor Innovative and Secure) is the one that has moved most rapidly from an idea to a viable, albeit still at the preliminary design stage, commercial entry. IRIS is a modular pressurized water reactor with an integral configuration (all primary system components—pumps, steam generators, pressurizer, and control rod drive mechanisms—are inside the reactor vessel). It is offered in configurations of single or multiple modules, each having a power rating of 1000 MWt (about 335 MWe). The IRIS program began in October 1999 as one of the winning proposals in the first Nuclear Energy Research Initiative (NERI) solicitation by the Department of Energy, and it has since progressed through the conceptual design and moved to a stage in the preliminary design, which has allowed initiation of the licensing process, with the first meeting with the Nuclear Regulatory Commission on pre-application licensing held in October 2002. IRIS is also one of the reactor designs considered in determining the envelope of the early site permit (ESP) by three U.S. power generation companies— Dominion, Entergy, and Exelon. This early success of IRIS is attributable to two fundamental constituents of the IRIS approach: ■ IRIS is a very innovative reactor design with many attractive new features, especially in the safety area, but at the same time its technology is grounded on well-proven and universally familiar water reactors experience. ■ IRIS embodies a new paradigm with its development by an international partnership of industry, research organizations, academia, and power producers for potential future deployment in both developed and emerging markets. While most reactor programs have some international participation, such participation is of the contractor/supplier type and is not a qualifying characteristic; the internationality of IRIS is one of its very raisons d’être.