The integral pressurized water reactor (iPWR) will play an important role in nuclear energy development considering its outstanding safety features. To achieve high proliferation resistance, extended fuel cycles have been proposed. Other important issues to achieve nuclear energy long-term sustainability are the proper use of its fuel sources and the improvement of nuclear waste management. Therefore, fuels based on oxides mixture have been successfully used in several countries. Also, Thorium-based fuel incorporation is a current challenge for the new advanced reactor designs. This paper compared different fuel compositions using recycled Plutonium and Uranium in a conceptual reactor of the type iPWR. The use of Thorium as fertile material is presented as well. The presented study considers a standard fuel cycle with slightly enriched Uranium (below 5%) as reference. One-third of the conceptual iPWR’s core is loaded with MOX fuel assemblies and the other two-thirds with conventional UO₂. These proposed fuel cycles are compared with the standard full-UO₂ cycle, regarding the behavior of main safety parameters, fuel depletion, and waste production. The studied fuel compositions reached a fuel cycle length of 4 years, approximately. The results for the core parameters show that using MOX and Thorium-based fuels in iPWR fulfills the safety constraints.

整体式压水堆（iPWR）因其突出的安全特性，将在核能发展中发挥重要作用。为了实现高抗扩散性，已提出延长燃料循环。实现核能长期可持续性的其他重要问题是正确使用其燃料来源和改进核​​废物管理。因此，基于氧化物混合物的燃料已在多个国家成功使用。此外，基于钍的燃料掺入是新的先进反应堆设计的当前挑战。本文比较了在 iPWR 型概念反应堆中使用回收钚和铀的不同燃料成分。还介绍了使用钍作为可育材料。所提出的研究将标准燃料循环与轻度浓缩铀（低于 5%）作为参考。概念 iPWR 堆芯的三分之一装有 MOX 燃料组件，另外三分之二装有常规 UO₂ . 这些提议的燃料循环与标准的全 UO ₂循环在主要安全参数、燃料消耗和废物产生的行为方面进行了比较。研究的燃料组合物达到了大约 4 年的燃料循环长度。核心参数的结果表明，在 iPWR 中使用 MOX 和基于钍的燃料满足安全限制。