Electification and Energy Management Systems in Maritime Ports : Modeling and Optimization Approach

Abstract

The maritime industry is a major contributor to global greenhouse gas emissions, accounting for 3 \% of total emissions. The global economy remains highly dependent on shipping as 90 \% of global goods are transported by sea. Ports are a central points of operation for transporting goods and people from sea to land and form centers of high energy consumption and high air and noise emissions. Port-based emissions are particularly harmful due to the proximity to large populations that experience the effects of local air pollution.

Electrification of port operations is presented as a key solution to reducing port based emissions and the reliance on fossil fuels. In ports, majority of emissions are caused by berthing ships, cranes, and cargo-handling operations, as well as land based logistics. Electrified ports enable the development for integrated port microgrids that combine loads and local power production under a single system. This enables implementing smart energy management systems to optimize port operations reducing costs and emissions as well as improve energy efficiency.

This thesis analyses energy usage in ports, identifying electrification opportunities, and operational flexibilities that support smart energy management. Additionally, energy management systems are further analyzed presenting the approaches for controlling port microgrids. A cost analysis study is presented using a Mixed-integer linear programming model of a passenger port with local solar production, battery energy storage and onshore power supply. This was used to analyze the operational cost benefits of smart energy management in ports as well as recognize how different patterns and components influence the results.

The findings present electrification of port machinery, providing ships with onshore power supply, and introducing renewable energy sources and energy storage in ports as a viable approach in reducing port based emissions and operational costs. Timing ship berthing, energy storage, refrigerated container yards, and cargo handling are recognized as key controllable flexibilities in port operations. Energy management systems utilize this flexibility through forecasts and optimization, to make short- and long-term power scheduling.

The cost analysis presented that an optimal scheduling reduced yearly operational costs by 6.4-12.2~\% depending on system configuration, aligning with figures presented in relevant literature. Sensitivity analysis showed that local production, battery energy storage capacity and power price had small but positive correlation with cost reduction, while demand had a strong negative correlation. This suggests that with more uncontrollable power demand relative to power production reduces the operational cost benefits of smart energy management. Analyzing price, demand, and solar patterns suggested that high price volatility as well as misaligned production and demand benefit smart energy management.