While previous research has focused on single industrial sectors or specific technologies, this study aims to explore the impacts of various industrial technology options on the use of biomass and electricity in a future fossil free Swedish industry. By building a small optimization model, that decomposes each industrial sector into site categories by type and technology to capture critical synergies among industrial processes. The results show important synergies between electrification, biomass and CCS/U (sequestration of CO₂ is required to reach net-zero emissions). Reaching an absolute minimum of biomass use within the industry has a very high cost of electricity due to the extensive use of power-to-gas technologies, and minimising electricity has a high cost of biomass due to extensive use of CHP technologies. Meanwhile, integrated bio-refinery processes are the preferable option when minimising the net input of energy. There is, thus, no singular best technology, instead the system adapts to the given circumstances showing the importance of a detailed bottom-up modelling approach and that the decarbonisation of the industry should not be treated as a site-specific problem, but rather as a system-wide problem to allow for optimal utilisation of process synergies.

There is great uncertainty about what technologies will be available in time to meet Swedish Government, 2017 net-zero emission target for the industrial sector. This study therefore investigated how the availability of innovative technologies affects cost-effective pathways to meeting this target. The investigation employed scenario analyses using TIMES-Sweden with a new techno-economic database of industrial technologies. The scenarios varied according to how the net-zero target was defined and which technologies could be used to meet the target. Technology readiness levels (TRLs) were used to define which and when new technologies were available for investments. Based on the scenario results, a technology prioritisation pattern was identified, indicating the conditions under which technology options generated cost-efficient solutions from a systems perspective. If carbon offsetting was allowed, then carbon capture and storage (CCS) was promoted, using biofuels as a supplement. When carbon offsetting was restricted, technologies using biofuels and/or electrification options were preferred. In all scenarios, the use of heat pumps and the integration of biofuel production in the forest industry, for example, strengthened sector coupling and were favoured for the efficient use of biomass. The results also revealed that a net-zero industry with restricted use of carbon offsetting relies on technologies with a TRL of 6 (on a scale of 9) to become available; in such cases, hydrogen electrolysis and black liquor gasification were key. When carbon offsetting was unrestricted, CCS technologies combined with low-cost negative emissions provided the most cost-efficient solution, but it led to fossil fuel lock-in. For Sweden, the local availability of biomass provides a competitive advantage when the use and production of biofuels both reduces the need for using more costly power-to-fuel solutions in industry and makes available low-cost negative emissions.

Despite the time-dependent behavior of carbon stored in plastic materials, literature assessing carbon flows into and from plastic typically applies a static approach. To better understand the climate impacts of such storage, this study explores how carbon stored in plastics can contribute over time to the national climate inventory with various emphasis on recycling. This is accomplished by implementing material stock change estimations for carbon in plastic materials that follow first-order decay and include impacts from recycling rates in the Integrated MARKAL-EFOM System model generator for Sweden (TIMES-Sweden). Thereafter, three approaches to how carbon released from the plastic material stock is accounted for in the national climate inventory were applied to determine how each approach affects resulting emission and net-zero pathways in different recycling rate scenarios. An accounting approach that follows the first-order decay pattern of material stocks was found to be important for capturing the impacts of recycling and for neither over- nor underestimating the emission impact from carbon stored in plastics. Accounting for carbon stored in plastics may provide important incentives for producing renewable plastics and reducing dependence on carbon removal technologies. Because of its synergies with recycling, the carbon storage potential of plastic products is well worth recognizing and promoting in a policy setting that aims for circularity. For Sweden, this reduces the need for bioenergy carbon capture and storage and makes more biomass-based carbon and electricity available for use elsewhere in the energy system.

By sharing their resources, individual countries could play an important role in supporting other countries ambition of reducing emissions. This study explores the costs and conditions for increased production and export of renewable olefins in Sweden while also reaching net-zero greenhouse gas emissions. We use the comprehensive energy system model TIMES-Sweden to generate a marginal cost curve and identify preferred technologies. The marginal cost curve is created by combining the cost of production for renewable olefins across 20 cases with successively increasing olefin export levels. The derived marginal cost curve for increased olefin production shows that using biomass in biorefineries and biogenic-CO2 in power-to-fuel concepts powered by wind power are the most competitive options for Sweden. A carbon fee on fossil plastic of 155-290 EUR/t CO2 can incentivize a production of 3.5 Mt renewable olefins in Sweden. At the same time, not recognising the potential negative emission contribution from carbon stored in plastic in combination with carbon removal credits provides a major policy uncertainty for increased production using biomass-based CO2. The required technology development for production of up to 8Mt renewable olefins imposes no new challenges to the energy system, they overlap with needs in other sectors. If high levels of olefin export are wanted, we urge policy makers to think bigger rather than different.