Cost and schedule reduction for next-generation Candu

AECL has developed a suite of technologies for CanduR reactors that enable the next step in the evolution of the Candu family of heavy-water-moderated fuel-channel reactors. These technologies have been combined in the design for the Advanced Candu Reactor TM1 (ACRTM), AECL's next generation Candu power plant. The ACR design builds extensively on the existing Candu experience base, but includes innovations, in design and in delivery technology, that provide very substantial reductions in capital cost and in project schedules. In this paper, main features of next generation design and delivery are summarized, to provide the background basis for the cost and schedule reductions that have been achieved. In particular the paper outlines the impact of the innovative design steps for ACR: - Selection of slightly enriched fuel bundle design; - Use of light water coolant in place of traditional Candu heavy water coolant; - Compact core design with unique reactor physics benefits; - Optimized coolant and turbine system conditions. In addition to the direct cost benefits arising from efficiency improvement, and from the reduction in heavy water, the next generation Candu configuration results in numerous additional indirect cost benefits, including: - Reduction in number and complexity of reactivity mechanisms; - Reduction in number of heavy water auxiliary systems; - Simplification in heat transport and its support systems; - Simplified human-machine interface. The paper also describes the ACR approach to design for constructability. The application of module assembly and open-top construction techniques, based on Candu and other worldwide experience, has been proven to generate savings in both schedule durations and overall project cost, by reducing premium on-site activities, and by improving efficiency of system and subsystem assembly. AECL's up-to-date experience in the use of 3-D CADDS and related engineering tools has also been proven to reduce both engineering and construction costs through more efficient work planning and use of materials, through reduced re-work and through more precise configuration management. Full-scale exploitation of AECL's electronic engineering and project management tools enables further reductions in cost. The Candu fuel-channel reactor type offers inherent manufacturing and construction advantages through the application of a simple, low-pressure low-temperature reactor vessel along with modular fuel channel technology. This leads to cost benefits and total project schedule benefits. As a result, the targets which AECL has set for replication units - overnight capital cost of $1000 US/kW and total project schedule (engineering/manufacturing/construction/commissioning) of 48 months, have been shown to be achievable for the reference NG Candu design. (authors)