Charting the evolution of biohydrogen production technology through a patent analysis

• Technology evolution roadmap model is constructed using patent analysis model.
• Technology evolution of fermentative hydrogen production from biomass is analyzed.
• Hydrogen production method based on biomass waste is currently the main trend.

This study models the evolution of technologies for hydrogen production from the fermentation of biomass. We used a patent-clustering method to construct a technology network based on the mutual citation relationships between representative technology patents. Subsequently, we established an approximate matrix by analyzing the density of this citation network and identified the core technology cluster. We evaluated 2125 US patents from 2012 related to fermentative hydrogen production from biomass and divided the patents into four clusters according to their main technological areas. The largest cluster featured “the methods and systems that process useful gas by using waste and wastewater as feedstock and by enhancing biological (e.g., aerobic and anaerobic) processes,” indicating that this technology area currently represents the mainstream technology for such hydrogen production.