High-temperature electrolysis for large-scale hydrogen and syngas production from nuclear energy – summary of system simulation and economic analyses

Abstract

A research and development program is under way at the Idaho National Laboratory (INL) to assess the technological and scale-up issues associated with the implementation of solid-oxide electrolysis cell technology for efficient high-temperature hydrogen production from steam. This work is supported by the US Department of Energy, Office of Nuclear Energy, under the Nuclear Hydrogen Initiative. This paper will provide an overview of large-scale system modeling results and economic analyses that have been completed to date. System analysis results have been obtained using the commercial code UniSim, augmented with a custom high-temperature electrolyzer module. Economic analysis results were based on the DOE H2A analysis methodology. The process flow diagrams for the system simulations include an advanced nuclear reactor as a source of high-temperature process heat, a power cycle and a coupled steam electrolysis loop. Several reactor types and power cycles have been considered, over a range of reactor outlet temperatures. Pure steam electrolysis for hydrogen production as well as coelectrolysis for syngas production from steam/carbon dioxide mixtures have both been considered. In addition, the feasibility of coupling the high-temperature electrolysis process to biomass and coal-based synthetic fuels production has been considered. These simulations demonstrate that the addition of supplementary nuclear hydrogen to synthetic fuels production from any carbon source minimizes emissions of carbon dioxide during the production process.

An Optimization Framework for Dynamic Hybrid Energy Systems

“…However, to properly utilize the available analysis and optimization tools, a system that more closely models the relevant physical phenomena is needed. This would entail replacing the signal block component models with, for example, process models for the HTSE [14] and equivalent-circuit models for the battery [15]. To retain reasonable computational cost, reduced-order models constructed using surrogate-based techniques may also be applied [16,17,18].…”

Review of the Potential of Nuclear Hydrogen for Addressing Energy Security and Climate Change

“…A 600 MW th high-temperature reactor coupled to a dedicated HTE plant would have a hydrogen production capacity of about 85 million SCFD [36], very similar to a large SMR plant. The economics of the nuclear-HTE option will improve as the demand for natural gas increases and reserves are depleted.…”

Large Scale Hydrogen Production From Nuclear Energy Using High Temperature Electrolysis

“…Accordingly, a number of detailed process models have been developed at INL for largescale system analysis of high-temperature electrolysis plants including both steam electrolysis and co-electrolysis of steam and carbon dioxide [15,21,56]. These analyses have been performed using UniSim process analysis software [31] which inherently ensures mass and energy balances across all components and includes thermodynamic data for all chemical species.…”

“…The scale of these SMR plants provides a basis of comparison to proposed nuclear HTE plants. A 600 MW th high-temperature reactor coupled to a dedicated HTE plant would have a hydrogen production capacity of about 85 million SCFD [56], very similar to a large SMR plant. The economics of the nuclear-HTE option will improve as the demand for natural gas increases and reserves are depleted.…”