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This paper establishes the concept of hybrid PV systems where the ratio of different photovoltaic (PV) technologies is optimized so that their combined output profile best matches user requirements. The method is presented and applied to a case study where a two‐axis tracking concentrating photovoltaic (CPV) and a single‐axis silicon photovoltaic (SiPV) system installed at a sub‐tropical location in Australia, are to power the production of hydrogen by electrolysis. The analysis quantifies the performance of the PV systems from data gathered at the site and reveals the complementarity of these two systems in their output at different timescales. An optimization problem is then defined that seeks the optimal ratio of CPV and SiPV to achieve high annual power output and, importantly, a good match between power supply and demand profiles. The benefits of this approach are illustrated for a green hydrogen power‐to‐gas‐to‐power plant under two operating modes. For this case study, the optimal PV ratio of 0.33CPV: 0.67SiPV leads to reduced dependence on the electricity grid, and a maximum guaranteed minimal take‐up of hydrogen over all months in a year. Overall, the sustainability of the plant is increased without the need for additional storage, and therefore additional resources. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multiple in-situ techniques with the same time/temperature scale were integrated. • Six steps that measure the length change of brick during firing are identified. • The mineralogical transformation is closely related to the heating protocol. • Clay mineral proportions and types in source materials affect fired brick strength. The mineralogical transformation of clay material is critical to the firing process for brick manufacturing. In this study, a series of in-situ integrated techniques are used to study the properties of two clay mixtures routinely for production of bricks at a local factory in Queensland, Australia. In-situ XRD, thermal expansion/contraction, thermal weight loss, and microstructural evolution of brick bodies at high temperature have been investigated. Illite/mica persists until 950 °C during the firing process, while K-feldspar transforms into plagioclase with the addition of Ca cations from starting materials. A slower ramp rate decreases the onset temperature of many reactions, including the decomposition of calcite and nucleation/crystallisation of mullite. An increase of firing temperature from 950 to 1150 °C has significantly enhanced the compressive strength of the prepared brick buttons. In addition, six length changing steps have been identified across the temperature range from 30 °C to 950 °C. The contraction of kaolinite between about 420 °C to 850 °C might compensate for the thermal expansion of typical bricks, and may minimise the potential for failure during the α- to β-quartz inversion. However, the rapid shrinkage of metakaolin above 850 °C increases the risk of cracking in manufactured bricks. [ABSTRACT FROM AUTHOR]