Optimization of Hybrid Renewable Electrical Energy Systems for a Port.

Abstract

The port terminals in South Africa currently face significant challenges linked to electricity constraints and security. South Africa is predominantly reliant on coal-generated electricity from the local utility for the provision of base-load electricity to power operations, and municipal distribution systems in many areas. A reduction in power in the latter part of 2015 has resulted in the curtailment of load shedding that is continuing to date, 2019. This risk is not mitigated, it is ongoing. Port terminals in South Africa rely on the throughput of the vessels to ensure that freight is moved speedily. The aspects of port operations that are generally considered in measuring port performance and efficiency are berth productivity measured in moves or volumes per ship working hour also known as across the shipping rate, cargo dwell times, crane moves per hour, ship turnaround time with less focus or no energy management. The port operations are dependent on the throughput of the operation. The energy consumed for port operations is thus independent and is difficult to control in any sort of energy management plan. Coupling this with the time of use tariffs and demand penalties, the need for an adaptable hybrid system can alleviate some stresses and contribute positively to an energy management plan. This study aims to determine that the distributed generation and storage performed by a variety of small, grid-connected referred to as distributed energy resources mitigate the energy cost issues in the port environment and reduction of Green House Gases (GHG) emissions. Distributed resources can help reduce the capacity problems to which an aging or overstressed grid is liable. The study is contributing to reducing dependence on major power plants supply and redirecting the source of supply to renewable technologies. This results in eliminating the need to erect new big power generation and deferral of new capacity. It also demonstrates that PV Solar and Wind Turbine Generation can reduce environmental impacts and gas greenhouse gas emissions. Compared to the coal power plants, distributed generators units are renewable or low emission generator-based sources. The Homer Grid simulation tool suggest distributed generation to be the solution for the port i.e., the hybrid supply that includes the integration of photovoltaic generation, wind power generation, battery energy storage system (BESS) into the electricity Municipal Grid. Both Matlab and HOMER Grid optimizations tools are used to outline different options for reducing electricity costs. These tools compare the costs and savings and uses a powerful optimization to find the system that maximizes savings. We used these tools to analyze the distributed generation grid potential, peak renewables penetration, ratio of renewable sources to total energy, and grid stability. The tools present different study cases with optimal results. The outcome shows a decrease in the cost of energy in the long term and can contribute towards the better energy management of the port.