The Offshore Floating Nuclear Plant (OFNP) design creatively builds on two established technologies, namely light water reactors (LWRs) and floating oil/gas platforms. Marine siting as well as several design features produce a particularly safe plant. The concept exploits the advances and experience in the construction of large floating structures in the oil/gas offshore industry and naval shipyards to decrease construction time and cost compared to standard nuclear power plants.

This work aims to compare the Net Present Value (NPV) of two different projects, when important uncertainties are taken into account:

- Construction of multiple (up to four) small modularunits (275 MW each)

- Construction of one single unit of equivalent power(1100 MW).

Some of the major sources of uncertainties in large and complex nuclear projects are price of electricity, construction cost, discount rate, years of operation, capacity factor and transportation costs. Such sources of uncertainty are quantified through specification of documented averages and reasonable ranges of variability.

This information is first used to perform a sensitivity analysis which shows that the NPV of an OFNP project is affected most strongly by price of electricity, construction cost and discount rate. Then, all uncertainties are assigned a probability distribution function (pdf) and combined with a Monte Carlo approach to generate a pdf for the NPV of a project.

The results show that construction of four small modular units is the preferred alternative as it is characterized by a higher average and median NPV. Additional qualitative advantages of the smaller modular units include the lower initial capital expenses, hence lower financial risk, and higher project flexibility overall.