Research Projects

With increasing concerns about climate change and fossil fuel depletion, the global energy landscape is shifting toward clean, renewable, and efficient energy systems. Hydrogen, with its high gravimetric energy density (~ 141.8 MJ/kg), emerges as a promising clean energy carrier; however, its low volumetric density (~ 0.01 MJ/L) hinders large-scale adoption. Ammonia, with 17.6 wt.% hydrogen content, moderate storage conditions (~ 10 bar, ~20 ºC), and widespread network for transportation, serves as an alternative hydrogen carrier. Hydrogen can be regenerated on-site via thermocatalytic ammonia cracking at 1 bar and ~ 600 °C. A novel solar tower simulator (STS) using a closed volumetric receiver has been developed for this purpose. The superheated ammonia, typically at 600 ºC and 1 bar, undergoes catalytic cracking, releasing product gases, nitrogen, and hydrogen at a high temperature (~ 400 ºC). The waste heat associated with these products, if not recovered for utilization, leads to a low system efficiency and a high energy demand. This proposal outlines a stepwise strategy to develop a novel waste heat recovery (WHR) and reuse sub-system to enhance the thermodynamic efficiency of the STS. The first phase involves a detailed modelling of the WHR mechanism for the STS will be performed to establish theoretical feasibility and to identify key design parameters. During this phase, various heat transfer fluids (HTFs), including thermal oils and nanofluids, are evaluated for optimal performance. Due to the complexity of early integration with the STS, a scaled, independent table-top test loop will be designed and analyzed to experimentally validate the WHR mechanism. This loop uses hot air as a heat source and water as the heat sink. It is designed using non-dimensional similarity principles to ensure results are scalable and relevant. This setup isolates the WHR and reuse sub-system for focused testing while avoiding ammonia-handling risks in early stages. Following successful validation, the refined WHR and reuse sub-system will be integrated into the STS to recover heat from superheated ammonia. Subsequently, the system will be adapted to recover and reuse the waste heat from the cracked gases. Final stages include techno-economic evaluation and development of generalized design guidelines for WHR and reuse sub-systems in hydrogen regeneration systems and other industrial applications. The expected result is a validated, modular, and scalable WHR design that enhances system efficiency and supports deployment in solar-based hydrogen production platforms. This contributes directly to India’s National Green Hydrogen Mission through energy-efficient thermal integration.