Hydrogen-fueled internal combustion engines in combined heat and power (CHP) systems: A decarbonization strategy

Abstract

The worldwide shift to low-carbon energy has generated interest in hydrogen-fueled internal combustion engines, especially when combined with Combined Heat and Power (CHP) systems. This study employs a dual-method approach that integrates thermodynamic modeling of hydrogen and natural gas internal combustion engines across diverse compression and air-to-fuel ratios, alongside screening tools from the U.S. EPA and the UK Department for Business, Energy, and Industrial Strategy to evaluate technical and economic feasibility. Results indicate that hydrogen engines attain a maximum of 214.6 horsepower and 48.75 % efficiency at a compression ratio of 16, surpassing natural gas in power output while preserving competitive efficiency. Integration with CHP systems facilitates overall system efficiency of up to 85 %, accompanied by a 35 % decrease in greenhouse gas emissions. The paper provides a comprehensive analysis of NOx emissions in CHP-hydrogen engines. It suggests mitigation measures, including lean operation, exhaust gas recirculation (EGR), and heat recovery optimization, to achieve environmental compliance. The study's primary contribution is the formulation of conclusions and the conceptualization of an efficient, energy-saving hydrogen-based combined heat and power model by implementing both thermodynamic cycle modeling and catalog-based system selection. This innovative method presents a practical system evaluation with comprehensive thermal and emissions analysis, providing a solid decarbonization strategy for high-performance, distributed power generation.