The role of electrification and hydrogen in breaking the biomass bottleneck of the renewable energy system – A study on the Danish energy system

The aim of this study is to identify the technical solution space for future fully renewable energy systems that stays within a sustainable biomass demand. In the transition towards non-fossil energy and material systems, biomass is an attractive source of carbon for those demands that also in the non-fossil systems depend on high density, carbon containing fuels and feedstocks. However, extensive land use is already a sustainability challenge and an increase in future demands threat to exceed global sustainable biomass potentials which according to an international expert consensus is around 10 – 30 GJ/person/year in 2050. Our analytical review of 16 scenarios from 8 independent studies of fully renewable energy system designs, and synthesis of 9 generic system designs, reveals the significance of the role of electrification and hydrogen integration for building a fully renewable energy system which respects the global biomass limitations. The biomass demand of different fully renewable energy system designs was found to lie in the range of 0 GJ/person/year for highly integrated, electrified, pure electrofuel scenarios with up to 25 GJ/person/year of hydrogen to above 200 GJ/person/year for poorly integrated, full bioenergy scenarios with no electrification or hydrogen integration. It was found that a high degree of system electrification and hydrogen integration of at least 15 GJ/person/year is required to stay within sustainable biomass limits.