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Methane pyrolysis has emerged as a promising low-carbon hydrogen production method, serving as a bridge from conventional fossil fuels to renewable energies (REs). A recent technique for sustainable hydrogen production involves the process of methane pyrolysis in molten salt. To better understand the potential of sustainable turquoise hydrogen production, this paper presents a techno-economic assessment of methane pyrolysis in molten salt combined with a high-temperature heliostat solar field. In addition, a high-temperature thermal energy storage (HTES) unit is utilized to ensure uninterrupted hydrogen production during periods of solar unavailability, thereby contributing to the economic viability of the overall system. The proposed system can produce about 9 tons of H 2 /day and 27 tons of solid carbon/day with a round-trip efficiency of 49.8 % and a levelized cost of hydrogen (LCOH) of 1.93 $/kg. To further decarbonize the process, the feasibility of utilizing REs as the source of electricity for the HTES was analyzed, yielding a synergistic achievement of clean and economic hydrogen production. This configuration resulted in a LCOH of 1.25 $/kg, after including the United States (US) clean hydrogen production tax incentives. The proposed system shows the potential to achieve the US Department of Energy target of 1 $/kg of hydrogen with a 20 % reduction in the cost of RE infrastructure. • Proposing a novel design for methane pyrolysis in molten salt based on heliostat solar field. • Utilizing high-temperature thermal energy storage for continuous hydrogen production. • Performing a comprehensive techno-economic analysis by including clean hydrogen tax incentives. • Reaching a hydrogen cost of 1.25 $/kg by incorporating the US clean hydrogen tax incentives. • Achieving the target of hydrogen shot (1 $/kg of H 2) through a 20 % reduction in the cost of RE infrastructure. [ABSTRACT FROM AUTHOR]

Abstract: Solar power tower (SPT) systems are viewed as one of the most promising technologies for producing solar electricity, in which direct solar radiation is reflected and concentrated by a field of giant mirrors (heliostats) onto a receiver placed at the top of a tower. However, the optimized design of a heliostat field is a rather complex problem because the annual performance of a heliostat is a function of not only the instants of time considered and its own position, but also the relative location of neighbouring heliostats, which cause shadows and blockings. A variety of procedures may be found in the open literature, although there is great lack of information on the details of an optimized layout. This review shows that these complex problems have partially led to the expansion of parabolic trough technologies in USA and Spain in spite of their lower thermodynamic efficiencies compared with solar tower power. As a modest support of SPT systems, the authors have presented elsewhere the abilities of a new code called campo for fast and accurate calculations of the shadowing and blocking factor for each and every heliostat. This work explores a review of the optimized heliostat field layouts yielded by campo. Campo commences the optimization search based on the densest layout, with the worst shadowing and blocking factor, but with good values for the other optical factors, and then progresses towards gradually expanded distributions. The search for maximum annual energy through campo results in a clear, steady and reproducible procedure. Finally, as an example of this new procedure, some options of optimized heliostat field layouts are reviewed using as input parameters the scarce open literature data on Gemasolar, the first solar power tower commercial plant with molten salt storage in the world. [Copyright &y& Elsevier]