Main title: Negative emissions in a future energy system: the role of biofuel and biochemical technologies Subtitle: Testing the robustness of Dutch strategies for achieving net-zero emissions in OPERA

Abstract

This research encompasses the use of mixed methods to answer the research questions, as both quantitative and qualitative methods were used. First, a quantitative assessment of residual and negative emissions in the baseline ADAPT and TRANSFORM scenarios was done. Then interviews and a workshop were organized to obtain qualitative data on biomass technology development. At the same time literature was studied to collect qualitative data on the development of biomass technologies. Thereafter, the OPERA model was run using an alternative scenario on technology development. The results of those runs were again quantitatively analyzed. Finally, mixed methods were used to determine alternative technologies in case the scaling of biofuel technology is too slow to realize sufficient negative emissions. This was based both on the modelling results as well as the literature study and opinions expressed in the interviews. This study has found that the pathways to negative emissions of current modelling studies are not robust. The interviews ascertained that the scale-up of biofuel and biochemical technologies in ADAPT and TRANSFORM is above realistic levels, especially in the short term. Non-technological obstacles are the dominant limitation to scale-up. Although some technological issues will have to be overcome during scale-up, the major concerns to project developers are biomass availability in the Netherlands, financing, and policy uncertainty. Modelling of a pessimistic technology development and cost scenario found a brief shift to biomass boilers and CHPs in 2035 when most alternative technologies were prohibited. Cost increases diverted biomethanol production to the use of external hydrogen. As a consequence CO2 could not be captured from the process. Similar conversion pathways are not available to other gasification technologies in OPERA. But this should be explored in future research. The most promising alternative technologies are constrained by a limited supply of feedstock. Bio-SNG and biomethanol production are the most viable technologies using woody biomass.