About 3 billion people use conventional carbon-based fuels such as wood, charcoal, and animal dung for their daily cooking needs. Cooking with biomass causes deforestation and habitat loss, emissions of greenhouse gases, and smoke pollution that affects people’s health and well-being. Hydrogen can play a role in enabling clean and safe cooking by reducing household air pollution and reducing greenhouse gas emissions. This first-of-a-kind review study on cooking with hydrogen assessed existing cooking technologies and hydrogen systems in developing country contexts. Our critical assessment also included the modelling and experimental studies on hydrogen. Renewable hydrogen systems and their adoptability in developing countries were analysed. Finally, we presented a scenario for hydrogen production pathways in developing countries. Our findings indicated that hydrogen is attractive and can be safely used as a cooking fuel. However, radical and disruptive models are necessary to transform the traditional cooking landscape. There is a need to develop global south-based hydrogen models that emphasize adoptability and capture the challenges in developing countries. In addition, the techno-economic assumptions of the models vary significantly, leading to a wide-ranging levelized cost of electricity. This finding underscored the necessity to use comprehensive techno-economic assumptions that can accurately predict hydrogen costs.

A battolyser is a combined battery electrolyser in one unit. It is based on flow battery technology and can be adapted to produce hydrogen at a lower efficiency than an electrolyser but without the need for rare and expensive materials. This paper presents a method of determining if a battolyser connected to a wind farm makes economic sense based on stochastic modelling. A range of cost data and operational scenarios are used to establish the impact on the NPV and LCOE of adding a battolyser to a wind farm. The results are compared to adding a battery or an electrolyser to a wind farm. Indications are that it makes economic sense to add a battolyser or battery to a wind farm to use any curtailed wind with calculated LCOE at £56/MWh to £58/MWh and positive NPV over a range of cost scenarios. However, electrolysers, are still too expensive to make economic sense.

High mass loading (ca. 30 mg/cm²) electrodes were prepared with carbon recovered from catalytic methane cracking (MC). As-fabricated supercapacitors displayed 74% of capacitance retention from 6 mA/cm² to 60 mA/cm² and a Ragone plot’s slope of −7 Wh/kW (compared to 42% and −31 Wh/kW, respectively, for high mass loading devices fabricated with commercial carbon). The high-rate capability of the MC-recovered carbon is attributed to the presence of carbon black and carbon nanotubes produced during the reaction, which likely increased the electronic and ionic conductivity within the electrode. These results suggest that the by-product of this hydrogen generation route might be a suitable active material for supercapacitors.

Prussian Blue is widely utilized as a cathode material in batteries, due to its ability to intercalate alkaline metal ions, including potassium. However, the exact location of potassium or other cations within the complex structure, and how it changes as a function of cycling, is unclear. Herein, we report direct insight into the nature of potassium speciation within Prussian Blue during cyclic voltammetry, via oper-ando potassium K-edge X-ray Absorption Near Edge Structure (XANES) analysis. Clear and identifiable spectra are experimentally differen-tiated for the fully intercalated (fully reduced Fe2+FeII Prussian White), partially intercalated (Prussian Blue; Fe3+FeII), and free KNO3(aq) elec-trolyte. Comparison of the experiment with simulated XANES of theoretical structures indicates that potassium lies within the channels of the Prussian blue structure, but is displaced towards the periphery of the channels by occluded water and/or structural water present resulting from [Fe(CN)6]4- vacancies. The structural composition from the charge carrier perspective was monitored for two samples of differing crystallinity and electrochemical stability. Reproducible potassium XANES spectral sequences were observed for crystalline Prus-sian blue, in agreement with retention of capacity; in contrast, the capacity of the poorly crystalline sample declined as the potassium became trapped within the partially intercalated poorly-crystalline Prussian blue. The cause of degradation could be attributed to a signif-icant loss of [Fe(CN)6]-[Fe(NC)6] ordering and the formation of a potassium-free non-conducting ferrihydrite phase. These findings demonstrate the potential of XANES to directly study the nature and evolution of potassium species during an electrochemical process.