I2S-LWR Top-Down Differential Economics Evaluation Approach

Abstract

The Integral Inherently Safe Light Water Reactor (I2S–LWR) is a design concept of a large (~1000 MWe) light water reactor with integral primary circuit configuration. One of the key design features promoting inherent safety is implementation of an integral primary circuit configuration, which in turn requires a compact design of the core and primary circuit components. Assessments of the cost of I2S-LWR is an important aspect of the overall evaluation of the new reactor concept. There are several approaches to cost estimation and economics evaluation of the new nuclear power technologies. Frequently used guidelines rely on the Code of Accounts, originally developed in the U.S. Department of Energy (DOE) Energy Economics Data Base (EEDB) Program Code of Accounts, proposed as evaluation tool by C.R. Hudson, and further popularized in the guidelines for economic evaluation of bids, by The International Atomic Energy Agency (IAEA). The code of accounts allows to break down main costs (Total Capital Investment Cost, Fuel Cycle Cost, Operation and Maintenance) to individual systems and items. This work aims to implement and apply a top-down differential economics evaluation approach to the Code of Accounts based guidelines, to assess the costs of the I2S -LWR relative to a representative “standard” PWR. In this methodology, a representative PWR design was taken as a reference and the differential cost was estimated for each individual account based on the design difference (or similarity). Cost estimating techniques were applied to the accounts representing systems that differ from the ones of the reference PWR. In this manner, the cost of the common components cancels out, and the uncertainty in the estimate is reduced. While this preliminary evaluation yet needs to be completed, the indications so far are that the I2S-LWR LCOE will be economically competitive with a standard PWR.