Energy Freight Transportation

Generally speaking, freight transportation is a vital component of the economy. It supports production, trade, and consumption activities by ensuring the effi­cient movement of raw materials and finished goods and their on-time deliv­ery. Transportation accounts for a significant part of the final cost of products and represents an important component of the national expenditures of any country [7].

Freight transportation has always been an integral component of economic development. It has now emerged as one of the most critical and dynamic aspects of the transport sector, where change has become the norm. Freight transportation is the main element supporting global commodities and. more generally, supply chains, complex and functionally integrated networks of production, trade, and ser­vice activities that cover all stages of production from the transformation of raw materials to market distribution and after-market services [8J.

The cost of a transportation system directly influences the cost of finished goods. The rising cost and complexity of shipping and delivering goods is adding to pressures faced by manufacturers and producers across the globe. However, as a result of the surge in global activities over the past 10 years, this issue has taken on new dimensions and importance. Thus, the freight-transportation industry must per­form at a high level in order to become economically efficient. With respect to quality standards, transportation has to offer high-quality services while being reliable.

The political evolution of the world also affects the transportation sector. This fact becomes more important as the significant political and economic role of energy is taken into consideration. The appearance and expansion of energy term­inals in increasing free-trade zones, political changes that result in new markets, and growing economic globalization have tremendous consequences for the evolution of transportation systems. Not all of the consequences are studied or understood well, and they need to be evaluated to become apparent.

NG is a vital component of the world's supply of energy. NG has made a strong comeback in the global energy balance since the mid-1970s as a direct response to increasing crude oil prices that began then. This development was given further impetus in the late 1980s in light of new concerns about potential global warming and climate change. The low-carbon intensity of NG (lowest among the fossil fuels) has made it the fuel of choice from an environmental point of view [1].

The transportation economics of NG, as one major form of energy, depend greatly on the annual volume of gas fields and transport distances. However, consum­ers or existing gas pipelines are usually at long distances from NG fields where gas pipelines cannot be built and operated economically. In developing countries, economical transporting and storing of NG is an important issue.

Two technologies have been introduced to condense NG to make it easy to transport safely. LNG and compressed natural gas (CNG) technologies have been applied in the gas industry for several years. LNG technology can reduce its vol­ume by about 620 times using the liquefaction of NG, whereas CNG technology reduces its volume by about 200 times using compression [5]. Unit transport costs and unit storage costs are greatly reduced by both technologies.

The production, processing, transportation, and consumption of LNG and associ­ated products are an issue of great interest in the energy industry. An LNG supply chain consists of loading ports shipping LNG to one or more receiving ports [9]. A typical supply chain is depicted in Figure 21.1. The loading ports and receiving ports structures are depicted in more detail in Figures 21.2 and 21.3, respectively.

NG is one of the cleanest, most efficient, and most useful of all energy sources. It is basically formed of methane but also contains heavier hydrocarbons such as ethane, propane, and butane. After extraction, it is purified to make it easier to transport and store. Impurities such as water, sulfur, sand, and other compounds make NG harder to transport, so they must be separated and removed.

In its raw form, NG is unsuitable for delivery, so it is condensed into a liquid at almost atmospheric pressure by cooling it to approximately -162°C. LNG is about 1/614th the volume of NG at standard temperature and pressure. To transport it over long distances where pipelines do not exist, it is carried by specially designed cryogenic vessels and cryogenic tankers and stored in specially designed tanks [10].

Huge advances in maritime transportation technology have been made in recent decades. These advances now increase opportunities to transport energy, oil in par­ticular, over long distances. Since 1980, the world's maritime fleet has grown in

Figure 21.3 The structure of a receiving port [9].

parallel with the seaborne trade. Table 21.1 shows the growth of world fleet in the period of 23 years from 1980 to 2003 [11].

The ocean shipping industry has a monopoly on the transportation of energy to faraway continents and countries. Pipelines are the only transportation mode that is cheaper than ships, but they are far from versatile because they can move only fluid types of energy over Fixed routes, and they are feasible and economical only under specific conditions. Other modes of energy transportation (rail and truck) have their advantages, but ships are probably the least regulated mode of transportation because they usually operate in international waters, and few international treaties cover their operations.

Pipeline transportation is more economical over short distances, whereas LNG shipping is more attractive over greater distances (12]. Once NG is in the transmis sion network, it travels from suppliers to customers over long distances. The gas network can be described as having supply nodes, demand nodes, and intermediate nodes. The gas is injected into the system through the supply nodes and flows out of the system through the demand nodes, which are also known as consumers Demand nodes are classified as electrical customers and nonelectrical customers |1|. Electrical customers are combined-cycle power plants that use the gas as fuel to produce electrical energy. Nonelectrical customers are the remainder of NG sys­tem customers.

Except for the two technologies, some technologies, especially natural»as hydrate (NGH) technology, are being developed to store and transport NG.

Energy in transit is exposed to unexpected dangers that may cause extensive damage to life, property, and environment. For NG, incidents such as leak or spill, irregular high or low temperatures, explosion, and Пате can occur as it is trans­ported or stored [10]. Industry analysts have analyzed the statistical likelihood of these events occurring simultaneously, and transient analysis has been used to derive the level of support necessary in pipe design to ensure there would be no system failure [6].

Safety is a high priority with companies that are in charge of moving and dis­tributing NG. It is very important that they analyze the probabilities of failure in the system, assess the worst results of such incidents, and provide guidance in developing safety and security requirements.

In addition to establishing rules for a well-functioning internal gas market, the European Community wanted to provide measures that would provide an adequate level of security for gas supplies. The directive (2004-2004/67/EC) set out certain instruments that were to be used by each member state to enhance security [13]. The instruments are as follows:

• Provide pipeline capacity to enable diversion of supplies and system flexibility.

• Transmit system operator cooperation to coordinate dispatch.

• Invest in infrastructure for gas imports in the form of regasification terminals and

pipelines.

The evolution of technology has also had a major influence on energy freight transportation. The problem is whether the transportation system can adapt to advances in new technologies and fuels and whether it will be well organized and operated in the new era. Freight transportation must perform within rapidly changing technological, political, and economic conditions and trends. Significant changes in technology are not about traditional hardware but about advances in information technology and software. The introduction of the Internet and the increasing use of it has dramatically changed the process of transportation, the way it is being con­trolled. and the interaction between carriers, shippers, and terminals.

Intelligent transportation systems, on the other hand, offer means to efficiently operate and raise new challenges, as illustrated by the evolution toward modifying planned routes to respond in real time to changes in traffic conditions or new detnands. More complex planning and operating procedures are a direct result of these new policies, requirements, technologies, and challenges [14]. Freight trans­portation must adapt to and perform within these rapidly changing political, social, _and economic conditions and trends. In addition, freight transportation is in itself a _c0mplex domain. Many different firms, organizations, and institutions, each with its own set of objectives and means, make up the industry. Infrastructure and even service modifications are capital intensive and usually require long implementation delays; important decision processes are often strongly interrelated. It is thus a domain in which accurate and efficient methods and tools are required to assist and enhance analysis, planning, operation, and control processes.