Currently, biomass utilization is predominantly directed toward bioenergy (BE) production. Yet, alternative pathways such as biochar carbon removal (BCR) and bioenergy with carbon capture and storage (BECCS) are emerging options within negative emission technologies. Given limited biomass resources, determining their most beneficial allocation remains a pressing question. This study addresses the research gap by jointly evaluating the private investment perspective (net private benefit, NPB) and the broader societal perspective (net social benefit, NSB). Through an integrated assessment framework, the analyses compare biomass utilization pathways across a range of technological, regulatory, and market developments. Herein, wheat straw in Germany was selected due to its high theoretical potentials. Under current conditions, BE shows the highest NPB, followed by BECCS, while BCR displays a negative NPB without policy or market adjustments. However, all pathways demonstrate positive NSB when environmental externalities are monetized. Scenario analyses indicate that BECCS can surpass BE in NPB with incentives such as higher carbon removal credit, cost reductions, or improved CO₂ storage infrastructure. BCR becomes NPB-positive under scenarios with either cost reductions or revenue increases. It surpasses BE only when both occur simultaneously but does not exceed BECCS in any scenario. As the energy sector decarbonizes, BCR and BECCS become increasingly competitive. The study emphasizes the need for flexible, context-dependent pathways and robust policy support to ensure that biomass utilization in Germany is viable from both private economic and societal standpoints.

The transition to a low-carbon economy necessitates effective carbon capture and storage (CCS) solutions, particularly for hard-to-abate sectors. Herein, pipeline networks are indispensable for cost-efficient (Formula presented.) transportation over long distances. However, there is deep uncertainty regarding which industrial sectors will participate in such systems. This poses a significant challenge due to substantial investments as well as the lengthy planning and development timelines required for (Formula presented.) pipeline projects, which are further constrained by limited upgrade options for existing infrastructure. The economies of scale inherent in pipeline construction exacerbate these challenges, leading to potential regret over earlier decisions. While numerous models were developed to optimize the initial layout of pipeline infrastructure based on known demand, a gap remains in addressing the incremental development of infrastructure in conjunction with deep uncertainty. Hence, this paper introduces a novel optimization model for (Formula presented.) pipeline infrastructure development, minimizing regret as its objective function and incorporating various upgrade options, such as looping and pressure increases. The model’s effectiveness is also demonstrated by presenting a comprehensive case study of Germany’s cement and lime industries. The developed approach quantitatively illustrates the tradeoff between different options, which can help in deriving effective strategies for (Formula presented.) infrastructure development.

The expansion of carbon dioxide removal (CDR) strategies is essential to achieve the climate targets. Among emerging CDR technologies, biochar holds particular promise due to its stable carbon storage and multiple co-benefits. While previous studies have examined the global potentials of biochar production, comprehensive assessments that include cost structures and spatial variability remain limited. This study addresses this gap and presents a comprehensive that integrates geospatial machine learning with techno-economic analysis to estimate region-specific biochar production costs at a global level. The derived approach estimates the biomass yields of various lignocellulosic biomass sources using an XGBoost machine learning model trained on climate and soil data. Roadside production costs are then calculated based on resource input parameters, followed by transport cost estimations using spatial distance metrics. Finally, pyrolysis costs are included to derive the total production cost of biochar per ton across regions globally. The results show substantial regional variation, with total production costs ranging from 113 to over 1500 €/ton. Sub-Saharan Africa, Latin America, and South Asia demonstrate the lowest median costs, below 300 €/ton, primarily due to low labor and biomass costs. Eucalyptus emerges as the most cost-efficient biomass provided it is cultivated. While the Kontiki flame curtain kilns are more cost efficient in low-income regions, advanced-technology plants become competitive in industrialized areas, especially when district heat is considered. These insights are crucial for guiding investments and policies that aim to expand biochar use as a viable and cost-effective CDR pathway.

The effectiveness of biochar as a soil amendment is highly dependent on local physical and chemical soil properties. Although the literature has already addressed biochar in several studies, there are still knowledge gaps. One the one hand, the relevant studies have primarily focused on field trials and small-scale applications at regional levels, overlooking the global perspective and regional differences. One the other hand, geospatial assessments lack quantitative evaluations and explanation, which are crucial for the model's applicability and the optimisation of biochar supply chains. Thus, this study addresses this gap by examining the impact of biochar on agriculture at a global scale. First, correlations between climate, soil, and fertiliser data, and maize yield are derived through Random Forrest machine learning algorithm. Subsequently, the relevant soil properties are adjusted to simulate the potential changes upon implementing biochar. Finally, the model projects the estimated maize yield following the introduction of biochar. Our findings demonstrate diverse effects of biochar, with notable increase in maize yield in arid regions of Africa and Asia. A substantial increase in maize yield is particularly expected in regions with a high bulk density, as biochar effectively loosens the soil, and in areas with a low soil organic carbon content, which is enhanced by biochar. Contrariwise, in northern South America, Central and North America, South-East Asia, and parts of Europe show low potential or even maize yield decreases. The model was also validated by comparing the results with 8 field trials from different countries, demonstrating a high level of accuracy. The outcomes are crucial for optimising biomass utilisation pathways, as it predicts the impact of biochar in different regions. Consequently, policy frameworks can be tailored to encourage biochar use in agriculture, especially in regions with the highest potentials, to fully leverage its sustainability and productivity benefits.

Carbon capture and storage will be necessary for some industries to reach carbon neutrality. One of the main associated challenges is the design of the network linking the CO ₂ sources to the storage sites. Establishing a CO ₂ network can be impacted by many uncertainties such as CO ₂ amounts, pipeline routes and the locations of emitters and carbon sinks. We present a framework to investigate different scenarios of a future CO ₂ network in Germany. The analyses compare the routes and associated costs of different scenarios. The developed model uses several geospatial datasets and an optimization scheme to yield realistic and cost-efficient outcomes. Parameters such as population density and existing infrastructure are integrated to calculate potential routes, which are then used as an input for the developed heuristic model to determine the optimum network. The derived framework is flexible and can be used for investigating other scenarios, regions and settings. The results show that the different scenarios have a profound impact on the optimal layout and costs. The investment costs of the investigated scenarios range between 1.3 and 3 billion EUR. The outcomes are important for academia, industry and policymaking for the ongoing discussions regarding the development of carbon infrastructure.

Conventional substrates like peat, stone wool and coconut coir are responsible for high greenhouse gas emissions in the horticultural sector, necessitating low-emission and cost-efficient alternatives. Herein, using miscanthus and biochar as substrate components as well as in cascading substrate application can be alternative practices in a sustainable bioeconomy. However, the carbon footprint and economic impacts of these practices in relation to crop yields have not yet been investigated. Hence, we combined life cycle carbon footprint assessment and costing to analyze the Global Warming Potential and value chain costs of horticultural substrates in tomato cultivation in North-Rhine Westphalia. We conducted a comparison between conventional substrates (peat, stone wool, and coconut coir) and single use and cascading miscanthus-based substrates with and without 1–2 % biochar addition of the miscanthus mass. Also, a subsequent scenario analysis was carried out to examine alterations in inputs and costs. Our results demonstrate that miscanthus-based substrates are climate-friendly and low-cost alternatives to the conventional practices. Switching to miscanthus-based substrates results in more emission savings than other input scenarios investigated. Additionally, incorporating biochar and adopting cascading methods contribute to lower emissions. Notably, biochar has the most significant impact, as its amount correlates with higher emission reductions. Additionally, costs for cascading miscanthus-based substrates are lower compared to conventional substrates. Overall, there is only a slight variance in costs between conventional and miscanthus-based substrates. However, with the introduction of carbon emission pricing and carbon removal certificates, miscanthus-based and biochar-containing substrates may emerge as more cost-efficient alternatives. Thus, by advancing financial instruments on carbon emissions and removal, introducing cascade use within and beyond the horticulture sector, and supporting cultivation of sustainable biomasses, miscanthus and biochar can effectively contribute to the development of a sustainable bioeconomy.

Polylactic acid (PLA) is the bioplastic with the highest market share. However, it is mainly produced from first-generation feedstock and there are various inconsistencies in the literature in terms of its production and recycling processes, carbon footprint, and prices. The aim of this study is to compile and contrast these aspects and investigate second-generation PLA production from technical, economic, and ecological perspectives simultaneously. The comprehensive analyses also show the chances and challenges of originating a PLA supply chain in a specific region. Herein, the German Federal State of North Rhine-Westphalia (NRW) has been chosen as a region of interest. In addition to highlighting the industrial capabilities and synergies, the study quantifies and illustrates the locations of different suitable second-generation feedstocks in the region. However, the identified potentials can be challenged by various obstacles such as the high demand of bioresources, feedstock quality, spatial aspects, and logistics. Furthermore, the substantial price gap between PLA and fossil-based plastics can also discourage the investors to include PLA on their portfolios. Thus, the study also provides recommendations to overcome these obstacles and promote the regional value chains of bioplastics which may serve as prototype for other regions.

North-Rhine Westphalia is the center of the German and European steel production. Its steel industry is heavily based on the primary production route and emits up to 30 Mt CO ₂ annually. One possible and increasingly prominent alternative to reduce these emissions is the hydrogen-based direct reduction. While this technology allows for a near climate-neutral production of primary steel, it poses substantial impacts on regional energy and material flows. Hence, the aim of this paper is to quantify the alterations in energy and material flows over time via integrating top-down energy and material flow models with bottom-up process models. The resulting values of emissions, energy, and material flows are then used to develop prospective scenarios that depict the requirements and consequences of potential pathways toward a climate-neutral steel production by 2045. The outcomes show that decarbonizing the North Rhine-Westphalian steel industry leads to an additional demand for renewable energies of up to 52.5 TWh per year, which represents 10% of the current electricity production in Germany. As securing the green electricity demand is a large challenge, the study also analyzes the impact of a partial recourse to natural gas as a reducing agent in combination with other measures like carbon capture and utilization/storage. The results show that such a recourse would reduce the electricity demand to 36.8 TWh. Hence, the paper illustrates relevant implications of the different scenarios, which can be used by policymakers to develop more realistic and resilient strategies for reaching carbon neutrality.