Global marine shipping annually accounts for about one billion tonnes of CO2 equivalent greenhouse gas emissions. Nuclear power propulsion may be an option to de-carbonise some niches of the merchant ocean fleet. This paper considers the three experimental nuclear-powered merchant ships launched and operated in the world so far; the iconic Savannah (USA), Otto Hahn (West Germany) and Mutsu (Japan). They were independently developed and operated in the 1960s and 1970s for technology demonstration and learning. A fourth ship, Sevmorput (Soviet Union/Russia, 1988–to date), is a pioneer in respect of its logistics functions and propulsion system. This paper develops a theoretical framework for the sustainability assessment of nuclear propulsion in ocean merchant shipping and presents a method for exploring nuclear propulsion, relative to flag state, ports, shipping resources and ocean transport services. The experimental ships’ transport efficiency is discussed and related to contemporary oil-fired shipping of general cargo, and to recent literature presenting possible future applications of merchant nuclear propulsion in some market niches. Insights provided include: (1) the experiments demonstrate that merchant nuclear propulsion may be technically feasible; (2) port and canal access for merchant nuclear-powered ships may be difficult and restricted; (3) the up-front costs, refuelling and end-of-life decommissioning costs of nuclear-powered ships are vast and uncertain against conventionally-powered ships; (4) because nuclear fuel is comparatively low-cost, the conventional oil-fired ship cost implications of high-speed operations do not apply.
This study presents a novel approach to forecast freight rates in container shipping by integrating soft facts in the form of measures originating from surveys among practitioners asked about their sentiment, confidence or perception about present and future market development. As a base case, an autoregressive integrated moving average (ARIMA) model was used and compared the results with multivariate modelling frameworks that could integrate exogenous variables, that is, ARIMAX and Vector Autoregressive (VAR). We find that incorporating the Logistics Confidence Index (LCI) provided by Transport Intelligence into the ARIMAX model improves forecast performance greatly. Hence, a sampling of sentiments, perceptions and/or confidence from a panel of practitioners active in the maritime shipping market contributes to an improved predictive power, even when compared to models that integrate hard facts in the sense of factual data collected by official statistical sources. While investigating the Far East to Northern Europe trade route only, we believe that the proposed approach of integrating such judgements by practitioners can improve forecast performance for other trade routes and shipping markets, too, and probably allows detection of market changes and/or economic development notably earlier than factual data available at that time.
A new power-to-X desulfurization technology has been examined. The technology uses only electricity to oxidize the hydrogen sulfide (H2S) found in biogas to elemental sulfur. The process works by using a scrubber where the biogas comes into contact with a chlorine containing liquid. This process is capable of removing close to 100% of H2S in biogas. In this paper a parameter analysis of process parameters has been carried out. In addition a long term test of the process has been performed. It has been found that the liquid flow rate has a small but notable influence on the process’ performance on removing H2S. The efficiency of the process largely depends on total amount of H2S flowing through the scrubber. As the H2S concentration increases, the amount of chlorine required for the removal process is also increased. A high amount of chlorine in the solvent may lead to unwanted side reactions.
The maritime industry is a crucial hard-to-abate sector that is expected to depend on high-energy density renewable liquid fuels in the future. Traditionally, decarbonization pathways have been assessed assuming exogenous cost trajectories for renewable liquid fuels based on an exogenous learning curve. While past studies have looked at the impact of endogenizing learning curves for a specific technology utilizing linear approximation, a fully endogenous direct non-linear implementation of learning curves in a detailed sectoral model (maritime industry) that explores dynamics concerning sensitive parameters does not yet exist. Here, we apply an open-source optimization model for decarbonizing the maritime industry and further develop the model by encompassing a nonconvex mixed-integer quadratically constrained programming approach to analyze the impact of endogenized learning curves for renewable fuel costs following an experience curve approach. We find that global greenhouse gas emissions are significantly lower (up to 25% over a 30 year horizon) when utilizing endogenously modeled prices for renewable fuels compared to commonly used exogenous learning frameworks. Furthermore, we find that conventional modeling approaches overestimate the cost of climate mitigation, which can have significant policy implication related to carbon pricing and fuel efficiency requirements. In a broader context, this emphasizes the potential opportunities that can be achieved if policymakers and companies accelerate investments that drive down the costs of renewable technologies efficiently and thus trigger endogenous experience-based learning in real life.
Large and remote offshore wind farms (OWFs) usually use voltage source converter (VSC) systems to transmit electrical power to the main network. Submarine high-voltage direct current (HVDC) cables are commonly used as transmission links. As they are liable to insulation breakdown, fault location in the HVDC cables is a major issue in these systems. Exact fault location can significantly reduce the high cost of submarine HVDC cable repair in multi-terminal networks. In this paper, a novel method is presented to find the exact location of the DC faults. The fault location is calculated using extraction of new features from voltage signals of cables' sheaths and a trained artificial neural network (ANN). The results obtained from a simulation of a three-terminal HVDC system in power systems computer-aided design (PSCAD) environment show that the maximum percentage error of the proposed method is less than 1%.
Adopting green vehicles in the transport sector is a highly effective policy for mitigating the sector’s carbon footprint. Moreover, the EU transport policy acknowledges the pivotal role of inland waterways (IWW) in decarbonizing Europe, with a strategic objective to enhance its modal share through the transition from road to IWW. This paper investigates the potential of electric autonomous Roll-on Roll-off (RoRo) ships to enhance the competitive edge of IWW as compared to road transport. This paper examines the impact of this innovative transport system on sustainability by analyzing Key Performance Indicators (KPIs) across economic and environmental dimensions using a comparative case study approach and quantitative analysis data. The main result is that implementing electric autonomous RoRo ships can lead to a 45 % reduction in OPEX (operational expenditure), with profitability expected after about 3.5 years. Emissions decrease by more than 60 %, and by 2030, CO2 emissions in the Well-to-Wake (WTW) cycle are projected to reduce by approximately 77,000 tonnes, aligning with EU transport and environmental policies.
This paper highlights the urgent need to accelerate research and action on ocean carbon sinks through human intervention, known as Global Ocean Negative Carbon Emissions (Global-ONCE) Programme, as a vital strategy in global efforts to mitigate climate change. Achieving 'net zero' by 2050 cannot rely on emission reductions alone, emphasising the necessity of complementary approaches. Global-ONCE's mission extends beyond scientific exploration. It embodies a profound commitment to protecting and restoring blue carbon ecosystems, as well as implementing ocean-based solutions that are sustainable, equitable, and inclusive. Early Career Ocean Professionals (ECOPs) are at the heart of these efforts, and their innovative approaches, technical expertise, and passion make them indispensable leaders in advancing ONCE initiatives. ECOPs bridge the gap between science and society, playing a relevant role in integrating cutting-edge research, technological advancements, and community-driven action to address climate threats. By bringing together diverse perspectives and leveraging their interdisciplinary expertise, ECOPs ensure ONCE strategies are grounded in scientific rigour and practical feasibility. Through advocacy, education, and collaboration, ECOPs not only spearhead research and innovation but also inspire collective action to safeguard our oceans. This paper amplifies the critical role of ECOPs as agents of change and calls for a unified global commitment to harness the ocean's potential for a climate-resilient future.
Closed-form expressions to estimate the energy absorption and damage extent for severe ship collision damages were initially developed in 1999 [1, 2], and further validated with experimental data in 2016 [3]. To gain further confidence for applications within design using the proposed analytical procedure, it is evident that more detailed and comprehensive comparisons and validations with experiments and numerical simulations are necessary. The purpose of the present paper is to use the analytical approach and finite element analyses to study in depth model-scale and full-scale collision tests so that to further quantify key calculation parameters and to verify the capability and accuracy of the proposed analytical method. In total 18 experimental tests and one full-scale collision accident are evaluated. The 18 experimental energy absorption-penetration and collision force-penetration curves, and the associated finite element simulations, are compared with results obtained from the analytical calculations. It can be concluded that the analytical method gives consistently good agreement with all experiments analysed here. Finally, an application of the analytical method is demonstrated by an example where speed restrictions are determined in a port to avoid LNG cargo leakage in an event of an LNG carrier being struck by another ship.
The 76th session of the Marine Environment Committee (MEPC 76) of the International Maritime Organization adopted several mandatory measures in June 2021 to reduce carbon emissions from ships. One of the measures is the carbon intensity indicator (CII), which is the carbon emissions per unit transport work for each ship. Several options of CIIs are available and none of them is chosen to be applied yet. We prove that, at least in theory, requiring the attained annual CII of a ship to be less than a reference value, no matter which CII option is applied, may increase its carbon emissions. Therefore, more elaborate models, combined with real data, should be developed to analyze the effectiveness of each CII option and possibly to design a new CII.
Maritime transport is the backbone of international trade. The amount of total international maritime trade in million tonnes loaded was 8408 in 2012 and had increased to 11.076 by 2019, for an average annual increase of 3.12%. In early 2020, the world fleet contained 98.140 ships of 100 gross tonnes and above with 2.06 million dead weight tonnage of capacity. The greenhouse gas (GHG) emissions from shipping activities are not negligible. According to the fourth GHG study commissioned by the International Maritime Organization (IMO), in 2018, global shipping emitted a total of 1056 million tonnes of carbon dioxide (CO2), accounting for around 2.89% of global anthropogenic CO2 emissions. Due to the international nature of shipping, efforts to control CO2 emissions from ships are absent from the Kyoto Protocol and the Paris Agreement. In an attempt to phase out carbon emissions from shipping entirely, the IMO formulated a strategy to cut the total annual GHG emissions from shipping by at least 50% from their 2008 levels by 2050; however, no mandatory rules have been promulgated since the release of this strategy.
Given the insufficient progress made by the IMO, the European Union (EU) decided to take a leading role in promoting the reduction of CO2 emissions from maritime transport. In 2015, the EU issued regulations on the monitoring, reporting, and verification (MRV) of CO2 emissions from ships with a gross tonnage above 5000 arriving at, within, or departing from ports under the jurisdiction of an EU member state, to come into force at the beginning of 2018. It should be noted that, under the MRV regime, even if only one port on a voyage is within the European Economic Area (EEA) and the other is not (e.g., a voyage from Rotterdam directly to Singapore), the ship must still report the total CO2 emissions of the whole voyage, rather than just the emissions of the part of the voyage within EU waters.
The MRV regime has been in operation for over two years, and the CO2 emissions data for the 2018 and 2019 reporting periods have already been published. Based on the data collected, on 16 September 2020, the European Parliament took the bold step of voting for the inclusion of maritime transport in the EU Emissions Trading System (ETS). This is a market-based system that uses economic tools such as a levy on bunker fuels and an emission trading system to provide monetary incentives for polluters to reduce emissions. The European Commission is conducting an impact assessment of the ETS, the results of which are expected in 2021. At this time, it is unclear how the inclusion of shipping into the EU ETS will work. There are two possibilities. The first is that only intra-EU voyages will be included; that is, only voyages from one EEA port to another EEA port will have to pay CO2 emission costs. The second is that both intra-EU voyages and voyages between an EEA port and a non-EEA port will have to pay CO2 emission costs, with the cost of a voyage between an EEA port and a non-EEA port being based on the CO2 emissions over the whole voyage, rather than the part of the voyage within EU waters. As the second possibility also covers the first possibility, we examine the implications of both possibilities but focus more on the second.