Virtually clean hydrogen from solar power and wood chips

 

Hydrogen can be made from solar energy splitting water and this is CO2 free however the Sun doesn’t shine all day and most systems to produce hydrogen involve some carbon dioxide emissions in some processes 1 kg of hydrogen would produce almost 30 kg of carbon oxide. A Kyoto University led team are developing a novel hydrogen plant design that can use biomass and solar energy and produce very low carbon dioxide emissions. They capture sunlight using special mirrors called heliostats that focus light onto receiver at the top of the tower structure this can reach up to 1000°C. This heat is transferred from the receiver into a gasifier where wood chips are intensely heated in the absence of oxygen. Rather than burning by combustion the wood chips are converted into a mixture of gases that contain a large proportion of hydrogen. The residue is solid carbon.



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