This study provides a comprehensive environmental impact assessment of different train types in Morocco, including passenger-only, goods-only, and mixed-use services. Through a comparative evaluation based on climate change, respiratory effects, and acidification/eutrophication, we find that passenger-only trains exhibit the highest environmental impact across all categories due to their high energy consumption and emissions. Conversely, goods-only and mixed-use trains display markedly lower environmental impacts, emphasizing the role of service type and operational efficiency in mitigating environmental harm. Our findings underscore the need for strategic optimization in train services, particularly passenger-only operations, and open the door for comprehensive economic and environmental assessments of alternative train technologies and fuel mixtures in the context of Morocco’s decarbonization plans.

This paper introduces a comprehensive approach for sizing grid-connected hybrid renewable energy systems tailored for electric bus fleet operations. The study involves two main steps. First, a mathematical model that optimizes the configuration of such systems by considering daily electric bus consumption, solar irradiance, wind speed, and biomass potential is formulated. The model utilizes Pareto frontier multi-objective optimization to minimize the net present cost, the cost of energy, and greenhouse gas emissions. Second, the model is rigorously applied and tested in a real-world case study in Fez, Morocco, using HOMER Pro; the case study centers on the daily energy requirements of the buses, estimated at 2.5 megawatt hours per day, with a peak demand of 345 kilowatts. Two scenarios are explored, revealing a discernible trade-off dilemma between the full hybrid renewable energy scenario (Scenario 1) and the grid-connected hybrid renewable energy scenario (Scenario 2). In Scenario 2, the grid-connected hybrid renewable energy system demonstrates a notable 42.8% reduction in the net present cost, totaling USD 984,624. Similarly, the levelized cost of energy experiences a significant decrease, reaching approximately 0.08 USD/kWh, marking a 38.1% reduction. However, this apparent economic advantage is juxtaposed with a critical consideration—an increase in greenhouse gas emissions from null to 330,418 kg/year.

This study introduces a novel methodology for conducting a techno-economic analysis of green ammonia production using mathematical models that meticulously parameterize plant units and technical specifications. The approach involves two key steps: first, identifying and modeling the essential components of green ammonia production, such as electrolyzers, ammonia synthesis units, and plant configurations; second, developing a non-linear optimization model to minimize the levelized cost of ammonia, payback period, internal rate of return, and return on investment. The model also incorporates constraints like maintaining minimum plant unit loads and optimizing electricity costs. By leveraging renewable energy through power purchase agreements, the study ensures a stable energy supply and carbon neutrality across the ammonia value chain. Two scenarios are examined: one with a user-defined electrolyzer configuration and another with an optimized configuration. In the latter, electricity consumption drops to 10 MWh per ton of ammonia produced, saving 60 GWh of energy annually, along with reductions in capital costs by 53% and operating costs by 10% compared to the first scenario.