Opportunities for peak shaving electricity consumption at container terminals

Opportunities for peak shaving electricity consumption at container terminals

Heij, R.

Tavasszy, L.A. (mentor)
Van Duin, J.H.R. (mentor)
Oey, M.A. (mentor)
Geerlings, H. (mentor)
Vloemans, P.H. (mentor)

Technology, Policy and Management

Transport & Logistics

2015-02-23

The throughput of containers is growing yearly (World Shipping Council, 2011). At the same time the capacity of containerships has grown from several hundreds of containers in the 1960s towards today’s 19,000 TEU carriers. In order to achieve efficient operations of these large containerships, container carriers require high handling speeds and low handling costs when visiting container terminals. This development stimulated continuous innovations at container terminals, resulting in growing automatisation of terminal operations. Where minimisation of costs has always been a key performance indicator for terminals, over the last decade the environmental performance has become another important performance indicator. This environmental performance is enforced by governments and port organisations as well as carriers who demand less emissions for handling their containers at a container terminal to improve the green image of their company and products. In order to save costs and to reduce the greenhouse gas emission (especially CO2) at container terminals, more terminal equipment gets powered by more environment-friendly energy sources like biodiesel, hybrid systems or electricity. Nowadays most modern container terminals are even fully electric. With a focus on higher handling speeds, the peak capacity of terminal equipment (i.e. number of terminal equipment that are operating at the same moment) increases. Because of the high price that is paid for the highest observed peak demand (leading up to 20-30% of the terminals’ energy bill), it is beneficial to keep the peak demand as low as possible to reduce handling costs. To investigate the opportunities for container terminals to reduce their peak demand, an energy consumption model is developed to visualise the energy consumption of terminal equipment at container terminals. The energy consumption model visualises the energy demand (kW/s) by focussing on the different movements that are executed by terminal equipment. This focus is important, since the energy consumption differs per movement. Hoisting a container consumes up to ten times more energy than a horizontal gantry movement. Based on the energy consumption model a simulation model is developed to test rules of operation (i.e. changes to the business operational procedures) that reduce the peak demand of terminals. Two rules of operation are tested to analyse their effect on peak demand and handling time: 1) limiting the number of simultaneously lifting quay cranes; 2) limiting the maximum energy demand per second. The potential reduction in peak demand is around 50% against an extra handling time of less than half a minute per hour. This can be achieved by reducing the maximum energy demand by 50%. By reducing the number of simultaneously lifting quay cranes the peak demand decreases up to 40%, which is lower than for limiting the energy demand per second. In this case the impact on terminal operations is also bigger, which makes it a less optimal solution. When reducing the peak demand by 50%, a container terminal with eight quay cranes is able to reduce their peak related energy costs with about €249,000 per year; a major potential saving for container terminals, which shows the opportunity for peak shaving the electricity demand at container terminals.

peak shaving
container terminals
electricity demand
energy consumption
terminal equipment
quay cranes
STS cranes

http://resolver.tudelft.nl/uuid:496725f4-ff7a-4319-bcaf-9e258e6dfe87

Student theses

master thesis

(c) 2015 Heij, R.