Search Results (8)

This study evaluates the financial viability of different main engine–fuel configurations for a container vessel on a standardized Trans-Pacific route. Using Net Present Value (NPV) analysis over a 10 year evaluation period (2024–2033), it compares six propulsion scenarios, combining three Wärtsilä engine types and four fuel alternatives (HFO, LFO, LNG, Methanol). The framework integrates technical parameters, including engine power and fuel consumption, with financial instruments such as the Weighted Average Cost of Capital (WACC) and the Capital Asset Pricing Model (CAPM). Results show that the LNG-powered Wärtsilä 8V31DF achieves the highest NPV. Despite requiring the highest initial capital expenditure (CAPEX), this configuration delivers superior financial performance and remains robust under volatile market conditions. Sensitivity tests with ±20% freight–fuel shocks and alternative discount rates (5%, 7.18%, 10%) confirm that the relative ranking of propulsion options is stable. Methanol yields negative NPVs under current prices but could become competitive with bio-methanol cost reductions or strong carbon pricing. Limitations include constant non-fuel OPEX, fixed sea state, and the exclusion of explicit carbon price scenarios. From a policy perspective, LNG appears most viable in the short term, while long-term strategies should consider ammonia and hydrogen in line with IMO decarbonization pathways. Full article

Articulated Tugs and Barges (ATBs) are increasingly recognised for their effectiveness in transporting chemicals, petroleum, bulk goods, and containers, primarily due to their exceptional flexibility and fuel efficiency. Recent projections indicate that the ATB market is on track for significant growth, which is expected to lead to an increase in the annual growth rate from 2025 to 2032. This study aims to analyse the current advancements in ATB technology and provide insights into the ATB fleet and the systems that connect tugboats and barges. Furthermore, it highlights the advantages of this transportation system, especially regarding its role in enhancing energy efficiency within the maritime transport sector. Currently, there is limited information available in the public domain about ATBs compared to other commercial vessels. The analysis reveals that much of the required information for modern ATB design is not accessible outside specialised design companies. The study also focuses on conceptual design aspects, which include the main dimensions, articulated connections, propulsion systems, and machinery, concluding with an evaluation of economic viability. Special emphasis is placed on defining the main dimensions, which is a critical part of the complex design process. In this context, the ratios of length to beam (L/B), beam to draft (B/D), beam to depth (B/T), draft to depth (T/D), and power to the number of tugs cubed (Pw/N³) are established as design control parameters in the conceptual design phase. This aspect underscores the novelty of the present study. Additionally, the economic viability is analysed in terms of both CAPEX (capital expenditures) and OPEX (operational expenditures). While CAPEX does not significantly differ between the methods used in different types of commercial ships, OPEX should account for the unique characteristics of ATB vessels. Full article

The growing scale of offshore wind farms and increasing transmission distances has driven the demand for optimized offshore substation (OSS) configurations. This study proposes a comprehensive techno-economic framework to minimize the total lifecycle cost (LCC) of an OSS by determining the optimal number of OSSs and transformers considering wind farm capacity and transmission distance. The methodology incorporates three cost models: capital expenditure (CAPEX), operational expenditure (OPEX), and expected energy not supplied (EENS). CAPEX considers transformer costs, topside structural mass effects, and nonlinear installation costs. OPEX accounts for substation maintenance and vessel operating expenses, and EENS is calculated using transformer failure probability models and redundancy configurations. The optimization is performed through scenario-based simulations and a net present value (NPV)-based comparative analysis to determine the cost-effective configurations. The quantitative analysis demonstrates that for small- to medium-scale wind farms (500–1000 MW), configurations using 1–2 substations and 3–4 transformers achieve minimal LCC regardless of the transmission distance. In contrast, large-scale wind farms (≥1500 MW) require additional substations to mitigate transmission losses and disruption risks, particularly over long distances. These results demonstrate that OSS design should holistically balance initial investment costs, operational reliability, and supply security, providing practical insights for cost-effective planning of next-generation offshore wind projects. Full article

The study examined the potential changing roles of ports in terms of diversifying their revenue through the expansion of new markets in the Port of Ngqura. This is by means of the production and sales of renewable hydrogen as marine fuel produced from a wavefarm in Nelson Mandela Bay. A key objective of the study was to conduct a comprehensive techno-economic analysis of the feasible hydrogen production technologies based on the analysis performed, including alkaline electrolysis of seawater and renewable-powered electrolysis of seawater. The produced hydrogen aligns with global decarbonisation of ships and ports and will be used to supply the port with electricity, serve to refuel tugboats, and provide green hydrogen bunkering fuel for commercial shipping vessels. The Port of Ngqura is geographically well positioned to lead the production of zero carbon shipping fuel. This work considers the CAPEX and OPEX of a hydrogen plant using electrolysers and evaluates the current cost of production and selling price of hydrogen. The primary aim of this study was to examine the feasibility of hydrogen production through electrolysis of seawater at the Port of Ngqura. Through assessing resource and technological options, determining advantageous economic assumptions, and identifying existing limitations and potential opportunities, a feasibility study was conducted with special consideration of the site characteristics of Ngqura. The output of this study is a model that simulates the production, storage, and transportation of hydrogen gas from the Port of Ngqura, which was further used to analyse different case study scenarios. This approach directly addresses the main goal of the study. The results found showed that with wave energy convertors in a row of three next to each other, the energy produced by the wave farm was 2.973 TJ per month, which is equivalent to 18.58 tons of produced hydrogen when considering the lower heating value of hydrogen and assuming that hydrogen production efficiency is 75%. The anticipated hydrogen fuel will be able to refuel a tugboat with green hydrogen from the energy produced by the wave farm each month. It is predicted that the price of hydrogen is expected to drop, and the price of fossil fuel will gradually increase in the coming years. The fact that coal electricity can be produced on demand and wind and solar energy are weather dependent as a result lacks the ability to achieve a constant supply. There is currently an urgent need for energy storage and the efforts to study the production of hydrogen and ammonia. Hydrogen is still predicted to be more expensive than coal electricity; however, from this, maybe a critical cost for a kg of CO₂ could be calculated, which could make hydrogen competitive. The cost of green hydrogen production from wave energy in the Port of Ngqura was calculated as R96.07/kg (4.88 EUR/kg) of produced hydrogen, which is equivalent to 2.1 times the cost of the same energy supplied as Marine Diesel Oil (MDO) at current prices. Hydrogen from wave energy would thus become competitive with MDO; if a price is set for the emission of CO₂, this may also offset the difference in cost between MDO and hydrogen from wave energy. The carbon price necessary to make green hydrogen competitive would be approximately R6257/tonne CO₂, or 318 EUR/tonne CO₂, which is around 4.5 times the current trading price of carbon in the EU Emissions Trading Scheme. Full article

The International Maritime Organization (IMO) and European Union (EU) have set targets to reduce greenhouse gas (GHG) emissions. Focusing on ships above 5000 GT, their measures exclude several ship types, such as fishing vessels, offshore ships, and yachts. However, smaller ships generate 15–20% of the total GHG emissions. Multiple potential fuel alternatives are already in use or have been investigated to minimize carbon emissions for coastal ferries. This study evaluates the possibility of using alternative fuels for small ferries by seven different parameters: technical readiness, presence of regulations, GHG emission reduction effectiveness (with two different criteria), capital expenditure (Capex), operating expenditure (Opex), and ice navigation ability. The assessment is based on an evaluation of state-of-the-art literature as well as second-hand statistics and press releases. The study also reports the most recent implementations in each alternative technology area. As a result, it was found that although there are several measures with high potential for the future, the most feasible fuel alternatives for coastal ferries would be fully electric or diesel-electric hybrid solutions. Full article

The recent inclusion of shipping in the Fit for 55 legislation package will have large knock-on effects on the industry and consequently on end consumers. The present paper presents an innovative top-down methodology, the MSF455 model, which estimates the new vessel Operational Expenditure (OPEX) as per the provisions of the Fit for 55 package and various scenarios based on carbon tax, penalty allowances, maritime fuel tax and effect. The methodology is presented and tested against six scenarios that are based on Det Norske Veritas’s (DNV) fuel maritime projections. The model illustrates that the distinction between intra-EU and extra-EU penalty allowance creates a large disparity and thus reduction in the competitiveness of goods (produced and transported). Full article

This article proposes an analytical model for a conversion from Heavy Fuel Oil (HFO) to Liquide Natural Gas(LNG) dual-fuel engine in a fleet with three sizes of vessels in order to investigate the impact of the volatility of oil prices, and a declining Energy Return on Investment (EROI) on opting LNG as a reliable marine fuel. This study also attempts to echo the importance of looking through a new window to the process of energy opting in the maritime industries to comply with International Maritime Organization (IMO) regulations. With giving this awareness to the maritime society the new investment can be directed to resources that effectively keep the maritime economy growing and can also help build a sustainable future. In order to find the best answer, we need to seek alternative solutions that will sustain shipping’s competitive edge. In the first phase, the impact of a declining EROI gas is investigated. Then, in the second phase, to be able to find an optimal area to run the vessels, we apply the Computerized Engine Application System (CEAS) in order to predict the engine performance of different container vessels and outlined fuel consumption in various market and technical situations. Since the process found is a non-linear system, this paper attempts to investigate the ongoing trend of the EROI of LNG in applying a Net Present Value (NPV) as a simulation method in order to observe the system to which technical variables or legal frameworks is more sensitive. In the following order, we first characterise the uncertainty faced by policy-makers and complexity dynamics implications for investment decision-makers and technology adoption. The practical relevance here of the proposed applied methodology is subsequently discussed in reference to four scenarios relating to the above areas and introduces the most beneficial area between different vital variables and constraints. It is applicable for the management of cascading uncertainties and the cross-sectoral impact by introducing the most beneficial area between various vital variables and constraints; including LNG prices, Capital Expenditure (Capex), Operating Expenditure(Opex) and time of enforcement. Full article

When designing “multi-MW arrays” of Wave Energy Converters (WECs), having a low number of converters with high individual power ratings can be beneficial as the Operation and Maintenance (O&M) costs may be reduced. However, having converters of small dimensions or small power ratings could also be beneficial, as suggested by previous works, due to a reduction in material costs as compared to power production, and the use of small, inexpensive vessels. In this work, a case study investigating the optimum size of WEC for a 20 MW array is performed. Analysis is carried out based on the CorPower Ocean technology. In this case study, firstly a Levelized Cost of Energy (LCOE) model is created. This model incorporates the latest Capital Expenditure (CAPEX) estimates for CorPower Ocean’s 250 kW prototype. Using this techno-economic model, several sizes/ratings of WEC are tested for use in a 20 MW array. Operational Expenditure (OPEX) is calculated using two different calculation approaches in order to check its influence on final indicators. OPEX is firstly calculated as a percentage of CAPEX, as shown in previous works, and secondly using a failure-repair model, taking into account individual failures of WECs in the array. Size/rating analysis is carried out for several European locations in order to establish any dependence between site location and optimal WEC size/rating. Several metrics for techno-economic assessment of marine energy converters, other than LCOE, are compared in this work. A comparison of several devices with each these metrics is performed within this study. Full article