Nuclear microreactors offer reliable, low-carbon dispatchable power and heat for various end use applications. Although the direct electricity end uses are straightforward, the feasibility of microreactors' integration for thermal end use has not been analyzed in literature in sufficient detail. Delivering process heat generated by nuclear microreactors to supply the high temperatures essential for hydrogen production has been proposed as one cogeneration option that can further aid in the alleviation of climate change, since hydrogen can replace carbon-emitting fuels such as gasoline, diesel or natural gas. This review provides a novel perspective on the intersection of microreactors and process heat use by investigating hydrogen production technologies, microreactor designs and process heat integration options. A comprehensive overview of hydrogen production methods including electrolysis and thermochemical conversions of hydrocarbons and water is presented by classifying the methods based on process temperatures and maturity. Additionally, an in-depth summary detailing the reactor type, power output, and maximum operating temperature of many prospective microreactor designs has been created. Finally, heat transfer options for integrating microreactors to hydrogen production systems were evaluated. The intermediate heat exchanger (IHX) assessment considers IHX material, IHX type, and heat transfer media utilized within the apparatus.

Fluid-Structure Interaction (FSI) is a significant phenomenon in most nuclear reactors, causing effects such as Flow-Induced Vibration (FIV) and thermally-driven Core-Radial Expansion (CRE). We demonstrate that Cardinal, an open-source coupling of NekRS and OpenMC to MOOSE, can be used for modelling FSI by coupling the Tensor Mechanics Module from the Multiphysics Object Oriented Simulation Environment (MOOSE) to NekRS's Arbitrary Lagrangian-Eulerian (ALE) solver. The solid mechanics-thermal hydraulics coupling is implemented using efficient in-memory coupling and data transfers. We provide a preliminary demonstration of these capabilities with a 3-D FSI benchmark for an elastic block in crossflow.

本文定性地回顾了适用于未来氢经济的日本能源系统建模的文献,利用定量建模结果进行了日本氢能源的未来潜在部署分析.着重分析了能源储存、天然气供应网补充、电力生产以及交通四个关键领域,详细说明了氢技术的潜在范围,这些技术有望渗透到2050年以后的日本能源市场.除了关键建模结果以外,还描述了支撑日本未来潜在氢经济的政策、治理机制以及市场机制.研究发现,由于鼓励制定更为远大的实施目标、对技术和研发的投资以及未来碳定价制度的兴起,氢能研究和利用在交通运输、天然气供应网补充以及储能等最终用途领域可能会得到迅猛发展.另一方面,日本氢能源最初依赖进口,而氢能源进口价格又对其他国家氢能源使用的发展(尤其是电力生产行业)有重要影响.此外,日本的人口结构特征是人口老龄化以及人口逐渐减少,将此认识与日本人的能源使用偏好结合考虑,可能有助于实现向氢经济的平稳过渡.

Using Japan as a proxy for a developed nation, we investigated the role of existing and nascent technologies in curbing carbon emissions. We simulated possible pathways to meeting 2030 and 2050 emission targets within the Japanese electricity supply sector using a single-region model in The Integrated MARKAL-EFOM System (TIMES). Critically, our simulations incorporate novel technologies like hydrogen electrolysers, carbon capture, photochemical water splitting, and emerging photovoltaic cells, assess long-term impacts up to the year 2100, and include life-cycle emissions and learning curves for parameters such as investment cost, efficiency, and emission coefficients. Results indicate that a hybrid approach, using nuclear power and hydrogen from renewable energy-based electrolysis, is cost-effective and provides long-term emission reduction along with energy security. Nuclear, wind, solar, and hydrogen from renewables emerge as key emission reduction technologies, while natural gas with carbon capture plays a minor role in achieving emission reduction targets.

This research qualitatively reviews literature regarding energy system modeling in Japan specific to the future hydrogen economy, leveraging quantitative model outcomes to establish the potential future deployment of hydrogen in Japan. The analysis focuses on the four key sectors of storage, supplementing the gas grid, power generation, and transportation, detailing the potential range of hydrogen technologies which are expected to penetrate Japanese energy markets up to 2050 and beyond. Alongside key model outcomes, the appropriate policy settings, governance and market mechanisms are described which underpin the potential hydrogen economy future for Japan. We find that transportation, gas grid supplementation, and storage end-uses may emerge in significant quantities due to policies which encourage ambitious implementation targets, investment in technologies and research and development, and the emergence of a future carbon pricing regime. On the other hand, for Japan which will initially be dependent on imported hydrogen, the cost of imports appears critical to the emergence of broad hydrogen usage, particularly in the power generation sector. Further, the consideration of demographics in Japan, recognizing the aging, shrinking population and peoples’ energy use preferences will likely be instrumental in realizing a smooth transition toward a hydrogen economy.