Payments are central to modern economies and societies yet concerns over the environmental impact of payment services are growing, especially from a climate perspective. This study examines the climate impact of retail payments in Sweden in 2021, including cash, cards, Giro payments, Swish, and payment apps. It builds upon established life cycle assessment (LCA) methodologies to measure the climate impact of retail payment services in the Swedish market, and evaluates their individual and aggregate climate impact. A full LCA is performed for cash, card, and app payments, while a screening LCA, considering only energy and GHG emissions, is applied to Giro and Swish. The study identifies areas to reduce overall impact and provides valuable information for sustainable decision-making related to payments. Total climate effect of card payments in Sweden is higher than those of cash, mainly due to a higher number of card transactions. However, the per-transaction climate impact of cash is higher than all other payment services. The research shows that the emissions from operational energy use for Swish and Giro are very low compared to cash and even card payments. Transitioning to digital payment systems therefore presents a clear opportunity to reduce the climate impact per transaction as well as per value transacted or per krona. Total system impact depends on transaction volume, infrastructure, and user behaviour, which can be shaped by supportive policies. The paper outlines key factors deciding the climate impact of retail payments which lay the foundation for future international comparative studies. 

Biomass is a key renewable feedstock for producing green fuels; however, renewable feedstock presents a high risk for catalyst deactivation and poor stability. In addition, the heat source of industrial reforming processes comes from fuel combustion and most heat is lost in the flue gas. In this study, a Ni/Al2O3/FeCrAl-based monolithic catalyst with a periodic open cellular structure (POCS) was designed and 3D-printed. A reforming process was then conducted by directly heating the catalyst using electricity instead of fuel combustion. This e-reformer technology was demonstrated in continuous catalytic steam reforming of biomass pyrolysis volatiles. A high H2 yield of ≈7.1 wt % of biomass has been obtained at a steam-to-biomass (S/B) ratio of 4.5, reforming temperature of 800 °C and weight hourly space velocity (WHSV) of 310 h−1, resulting in an energy consumption of 8 kWhel kg−1 biomass (66% energy efficiency). The results show a successful demonstration of the electrified technology with improvement potential; in addition, a process was designed and assessed economically for synthetic natural gas (SNG) production of 80 MWHHV, comparing electrification and partial oxidation in different scenarios.

This chapter explores the critical role of fuels for marine propulsion. Maritime shipping is vital for international trade and is often considered a relatively energy-efficient mode of transport. Yet, maritime shipping is heavily dependent on fossil fuels and contributes approximately 3% of annual global greenhouse gas emissions. This chapter discusses the different fuels used in maritime shipping and examines transitions toward alternative fuels, such as biofuels, electrofuels, and hydrogen. The chapter also highlights the role of policy and infrastructural needs for scaling-up transitions to low- and zero-carbon energy sources in the maritime shipping industry.

The global Sustainable Development Goals highlight the necessity for affordable and clean energy, designated as SDG7. A sustainable and feasible biorefinery concept is proposed for the carbon-negative utilization of biomass waste for affordable H2 and battery anode material production. Specifically, an innovative tandem biocarbon + NiAlO + biocarbon catalyst strategy is constructed to realize a complete reforming of biomass pyro-vapors into H2+CO (as a mixture). The solid residues from pyrolysis are upgraded into high-quality hard carbon (HCs), demonstrating potential as sodium ion battery (SIBs) anodes. The product, HC-1600-6h, exhibited great electrochemical performance when employed as (SIBs) anodes (full cell: 263 Wh/kg with ICE of 89%). Ultimately, a comprehensive process is designed, simulated, and evaluated. The process yields 75 kg H2, 169 kg HCs, and 891 kg captured CO2 per ton of biomass achieving approx. 100% carbon and hydrogen utilization efficiencies. A life cycle assessment estimates a biomass valorization process with negative-emissions (−0.81 kg CO2/kg-biomass, reliant on Sweden wind electricity). A techno-economic assessment forecasts a notably profitable process capable of co-producing affordable H2 and hard carbon battery anodes. The payback period of the process is projected to fall within two years, assuming reference prices of 13.7 €/kg for HCs and 5 €/kg for H2. The process contributes to a novel business paradigm for sustainable and commercially viable biorefinery process, achieving carbon-negative valorization of biomass waste into affordable energy and materials.

Aviation and maritime shipping are hard-to-abate transport sectors that are heavily dependent on fossil fuels. They jointly account for nearly 10 % of global greenhouse gas emissions, while infrastructure and investments are locked into high-carbon pathways for decades. Fuels and technologies to decarbonize include advanced biofuels, electrofuels, hydrogen and electric propulsion. This research aims to analyse the decarbonization strategies for maritime shipping and aviation from a comparative perspective, and analyzing the role of different actors for disruption to break through carbon lock-in and path dependency. The research uses Sweden as a case study and applies qualitative methods, including expert interviews, focus group discussions and site visits. Our research finds that aviation and maritime shipping are slowly changing, albeit with different dynamics. Both sectors show that incumbent regime actors play a major role in shaping transition pathways and disrupting the (quasi)equilibrium, while niche innovation is often developed together by incumbents and niche players.

This study introduces a distributed electrified heating approach that is able to innovate chemical engineering involving endothermic reactions. It enables rapid and uniform heating of gaseous reactants, facilitating efficient conversion and high product selectivity at specific equilibrium. Demonstrated in catalyst-free CH4 pyrolysis, this approach achieves stable production of H2 (530 g h−1 L reactor−1) and carbon nanotube/fibers through 100% conversion of high-throughput CH4 at 1150 °C, surpassing the results obtained from many complex metal catalysts and high-temperature technologies. Additionally, in catalytic CH4 dry reforming, the distributed electrified heating using metallic monolith with unmodified Ni/MgO catalyst washcoat showcased excellent CH4 and CO2 conversion rates, and syngas production capacity. This innovative heating approach eliminates the need for elongated reactor tubes and external furnaces, promising an energy-concentrated and ultra-compact reactor design significantly smaller than traditional industrial systems, marking a significant advance towards more sustainable and efficient chemical engineering society.

The maritime shipping industry accounts for 3 % of global greenhouse gas emissions and delivers 90 % of globally traded goods. Maritime shipping is heavily reliant on fossil fuels. There is increasing policy pressure to cut emissions to achieve the Paris Agreement and to meet decarbonization targets. This paper aims to analyze sector coupling for decarbonization and sustainable energy transitions in maritime shipping, exploring the interlinkages between the transport, energy, industry, agriculture and forestry sectors. First, this paper analyses the opportunities and barriers for sector coupling between the maritime shipping sector and other industries. Second, this paper adds new knowledge on the wider implications of sustainable energy transitions and decarbonization for the maritime shipping sector, the role of various stakeholders in supporting or impeding sustainable energy transitions, policy issues at the international, regional and national level and the links to sector coupling. This research uses a mixed methods approach, applying both qualitative research including interviews and quantitative energy modeling. The research thereby links theories from sustainability transitions with techno-economic modeling approaches. Our research finds that the sector couplings between the transport, energy, industry, agriculture and forestry sectors are of growing importance as maritime shipping is transitioning towards decarbonized and renewable marine fuels. At the same time there is competition for scarce natural resources with other sectors, including aviation and road transport. Socio-technical aspects, particularly of financial and political nature, are key factors that determine the speed and direction of the transition, yet they remain under-explored.

Bioenergy with carbon capture and storage (CCS) in iron and steel production offers significant potential for CO2 emission reduction and may even result in carbon-negative steel. With a strong ambition to reach net-zero emissions, some countries, such as Sweden, have recently proposed measures to incentivise bioenergy with CCS (BECCS), which opens a window of opportunities to enable the production of carbon-negative steel. One of the main potential applications of this route is to decarbonise the iron reduction processes that account for 85 % of the total CO2 emission in the iron and steel plants. In this study, gasification is proposed to convert biomass into biosyngas to reduce iron ore directly. Different cases of integrating the biomass gasifier, Direct Reduced Iron (DRI) shaft furnace, and CCS are evaluated through process simulation work. Based on the result of the work, the proposed biosyngas DRI route has comparable energy demand compared to other DRI routes, such as the well-established coal gasification and natural gas DRI route. The proposed process can also capture 0.65-1.13 t of CO2 per t DRI depending on the integration scenarios, which indicates a promising route to achieving carbon-negative steel production.

This article investigates the potential of renewable and low-carbon fuel production for the maritime shipping sector, using Sweden as a case in focus. Techno-economic modelling and socio-technical transition studies are combined to explore the conditions, opportunities and barriers to decarbonising the maritime shipping industry. A set of scenarios have been developed considering demand assumptions and potential instruments such as carbon price, energy tax, and blending mandate. The study finds that there are opportunities for decarbonising the maritime shipping industry by using renewable marine fuels such as advanced biofuels (e.g., biomethanol), electrofuels (e.g., e-methanol) and hydrogen. Sweden has tremendous resource potential for bio-based and hydrogen-based renewable liquid fuel production. In the evaluated system boundary, biomethanol presents the cheapest technology option while e-ammonia is the most expensive one. Green electricity plays an important role in the decarbonisation of the maritime sector. The results of the supply chain optimisation identify the location sites and technology in Sweden as well as the trade flows to bring the fuels to where the bunker facilities are potentially located. Biomethanol and hydrogen-based marine fuels are cost-effective at a carbon price beyond 100 €/tCO2 and 200 €/tCO2 respectively. Linking back to the socio-technical transition pathways, the study finds that some shipping companies are in the process of transitioning towards using renewable marine fuels, thereby enabling niche innovations to break through the carbon lock-in and eventually alter the socio-technical regime, while other shipping companies are more resistant. Overall, there is increasing pressure from (inter)national energy and climate policy-making to decarbonise the maritime shipping industry.