AIS-Based Estimation of Hydrogen Demand and Self-Sufficient Fuel Supply Systems for RoPax Ferries

The International Maritime Organization (IMO) established new strategies that could lead to a significant reduction in the carbon footprint of the shipping sector to address global warming. A major factor in achieving this goal is transitioning to renewable fuels. This implies a challenge, as not only ship-innovative solutions but also a complete low-carbon fuel supply chain must be implemented. This work provides a method enabling the exploration of the potential of low-carbon fuel technologies for specific shipping routes up to larger sea regions. Several aspects including vessel sizes, impact of weather and shipping routes, emissions savings and costs are considered. The local energy use is determined with proven bottom-up prediction methods based on ship positioning data from the Automatic Identification System (AIS) in combination with weather and ship technical data. This methodology was extended by an approach to the generation of a basic low-carbon fuel system topology that enables the consideration of local demand profiles. The applicability of the proposed approach is discussed at hand via a case study on Roll-on/Roll-off passenger and cargo (RoPax) ferries transitioning from conventional fuels to a compressed hydrogen fuel system. The results indicate a potential reduction in emissions by up to 95% and possible system sizes and costs

Estimating Hydrogen Usage of a Crew Transport Vessel Fleet for Offshore Windfarm Maintenance

Using hydrogen fuel may help to decarbonize maritime transportation. This paper presents an estimate for the mass of hydrogen that would be needed to power the current fleet of crew transport vessels used for maintaining the German offshore wind farms. The estimate is based on a calculation of the marine diesel oil consumption of the current fleet. We use vessel position data, weather data, and diesel consumption estimates to perform this calculation. Various hull shapes are used in small coastal vessels. This creates a challenge to estimate their energy needs. As a shortcoming, certain effects are excluded from the current estimate. However, this work presents an approach that can be improved and used for estimating hydrogen consumption in future scenarios. In these scenarios, a vessel type and parameters can be set. While here the challenge was to create a generic model that can be applied to multiple types of vessels

CMTM6 shapes antitumor T cell response through modulating protein expression of CD58 and PD-L1

The dysregulated expression of immune checkpoint molecules enables cancer cells to evade immune destruction. While blockade of inhibitory immune checkpoints like PD-L1 forms the basis of current cancer immunotherapies, a deficiency in costimulatory signals can render these therapies futile. CD58, a costimulatory ligand, plays a crucial role in antitumor immune responses, but the mechanisms controlling its expression remain unclear. Using two systematic approaches, we reveal that CMTM6 positively regulates CD58 expression. Notably, CMTM6 interacts with both CD58 and PD-L1, maintaining the expression of these two immune checkpoint ligands with opposing functions. Functionally, the presence of CMTM6 and CD58 on tumor cells significantly affects T cell-tumor interactions and response to PD-L1-PD-1 blockade. Collectively, these findings provide fundamental insights into CD58 regulation, uncover a shared regulator of stimulatory and inhibitory immune checkpoints, and highlight the importance of tumor-intrinsic CMTM6 and CD58 expression in antitumor immune responses

AIS-Based Estimation of Hydrogen Demand and Self-Sufficient Fuel Supply Systems for RoPax Ferries

The International Maritime Organization (IMO) established new strategies that could lead to a significant reduction in the carbon footprint of the shipping sector to address global warming. A major factor in achieving this goal is transitioning to renewable fuels. This implies a challenge, as not only ship-innovative solutions but also a complete low-carbon fuel supply chain must be implemented. This work provides a method enabling the exploration of the potential of low-carbon fuel technologies for specific shipping routes up to larger sea regions. Several aspects including vessel sizes, impact of weather and shipping routes, emissions savings and costs are considered. The local energy use is determined with proven bottom-up prediction methods based on ship positioning data from the Automatic Identification System (AIS) in combination with weather and ship technical data. This methodology was extended by an approach to the generation of a basic low-carbon fuel system topology that enables the consideration of local demand profiles. The applicability of the proposed approach is discussed at hand via a case study on Roll-on/Roll-off passenger and cargo (RoPax) ferries transitioning from conventional fuels to a compressed hydrogen fuel system. The results indicate a potential reduction in emissions by up to 95% and possible system sizes and costs

A simulation-based approach for evaluating merchant fleet decarbonization strategies

The International Maritime Organization (IMO) aims to reduce the annual greenhouse gas emissions from international shipping by at least 50 % by 2050, compared to 2008. To this end, the organization has adopted a set of regulations, including the Energy Efficiency Design Index (EEDI), the Energy Efficiency eXisting ship Index (EEXI), and the Carbon Intensity Indicator (CII), which will require the maritime industry to transition to lower carbon operations. However, the issue of how this transition is to be achieved remains unresolved. Against this background, this paper proposes a simulation-based approach for predicting how a selected fleet of merchant ships may develop over time under various decarbonization strategies. The aim is to make it possible to identify and evaluate feasible decarbonization strategies, accounting for potential bottlenecks, for instance in terms of the supply and availability of individual low-carbon fuels and technologies. A case study is presented in which the approach is applied to a fleet of 254 ships, which is assumed to be roughly representative of ships above 400 gross tonnage serving German ports