Probably the same or longer. In fact, the NuScale concept has been pursued since 2002, so more like 2 decades from concept to NRC certification. And you can tack on another 10 years for their hardware demonstration according to their published timelines. Size is not the question here. It's the analysis of the neutronics, thermal hydraulics, coupling of various systems, accident sequence prediction, etc. What takes time is credibility, ultimately getting all the parties involved to believe the calculations and understand the engineering decisions, and collectively agree that it's gonna work out. Have to convince the regulators, the advisory boards, the utility customers, the DOE, the suppliers.
