**3. Energy analysis**

In the transport sector, mainly fuels based on crude oil are used, so there is a high dependence on fossil fuels. While diesel fuel showed a steady growth in Europe for several decades, gasoline fuel is now becoming more important again, according to the European Automobile Manufacturers Association (ACEA) [14]. Recently, dual-fuel gasoline/diesel engines were presented [15]. Electric vehicles are strongly on the rise and are expected to replace cars with internal combustion engine in future [16, 17].

The movements of goods and people are very different transport processes and are also recorded differently. It is customary to specify the transport performance in the freight sector in tonne kilometers (tkm) or in person kilometers (pkm). The transport service refers to the distance covered in the respective territory.

The steady growth of online commerce has and will continue to have a major impact on the transport sector in future [18].

Large online mail order companies promote the digitization of trade and thus the amount of goods that have to be transported to the end users. In Germany alone, freight traffic has risen by about 120% since 1990 [19]. Thus, the traffic volume takes up about 26% of the traffic-related energy consumption [20]. The strongest increase is recorded in road and rail transport. For the transport sector, energy intensity indicators are collected on the basis of energy consumption and the transport performance provided.

These energy intensity indicators are used as a statistical measure of energy efficiency. In order to support the sustainable development of economic and livelihood models, indicators in the transport sector should include resource efficiency. Due to the large increase in freight traffic in recent years, the objective within freight transport should be to decouple growth in terms of increased transport performance and CO2 emissions. Energy consumption in freight transport related to rail and aviation is around 15% in aviation and 2% in rail transport, respectively [4].

Overall, it can be summarized that the energy consumption has increased less than the transport performance. Thus, it can be concluded that energy efficiency in freight transport has increased, but growth is neutralizing the efficiency gains achieved [4].

As it can be seen in **Figure 3**, aviation has the highest specific energy consumption. Low oil prices encourage the (continued) use of older, less energy-efficient cargo aircraft, making them economically viable again or extending their useful

**117**

*Energy Efficiency Management: State of the Art and Improvement Potential Analysis…*

lifetime. This could have an impact on indicator development. In the second place is the use of trucks, which are logistically almost inevitable due to the infrastructure

*Development of specific energy consumption in freight traffic by mode of transport from 1995 to 2013* 

Atmospheric CO2, which stands at ~400 ppm, is both harmful and vital. Without the significant greenhouse gas CO2 and other natural greenhouse gases, the Earth's average surface temperature would be sub-zero, and life would not be possible. This natural balance is disturbed by excessive and increasing anthropogenic CO2 emissions. These disturbances lead to global warming, which has developed since the Industrial Revolution (~1750) and increased significantly in recent years [3, 22]. The steadily growing globalization is making a significant contribution to the greenhouse gas effect. Carbon dioxide is also produced in combustion processes of engines and other equipment, with most of the artificial and harmful CO2 emissions caused by the industrialized countries. In addition to carbon dioxide, e.g., methane (CH4) and nitrous oxide (N2O) contribute to the environmental impact. These gases have a higher global warming potential (GWP) than CO2 [23]. All

Natural greenhouse gases act as a kind of filter that lets the (short wavelength) sun's rays through and captures the heat radiation (long wavelength) from the Earth's surface, thereby enabling regulated global warming. The functioning of a greenhouse is also used, for example, in plant breeding. Colloquially, the term greenhouse

greenhouse gases can be converted into CO2eq (CO2 equivalents) [3].

**4.1 Natural and anthropogenic greenhouse effect**

in most countries, particularly for "last mile" delivery.

**4. CO2 emissions**

*(modified from [21], p. 246).*

**Figure 3.**

*DOI: http://dx.doi.org/10.5772/intechopen.86552*

*Energy Efficiency Management: State of the Art and Improvement Potential Analysis… DOI: http://dx.doi.org/10.5772/intechopen.86552*

**Figure 3.**

*Transportation Systems Analysis and Assessment*

**3. Energy analysis**

**Figure 2.**

In the transport sector, mainly fuels based on crude oil are used, so there is a high dependence on fossil fuels. While diesel fuel showed a steady growth in Europe for several decades, gasoline fuel is now becoming more important again, according to the European Automobile Manufacturers Association (ACEA) [14]. Recently, dual-fuel gasoline/diesel engines were presented [15]. Electric vehicles are strongly on the rise and are expected to replace cars with internal combustion engine in future [16, 17]. The movements of goods and people are very different transport processes and are also recorded differently. It is customary to specify the transport performance in the freight sector in tonne kilometers (tkm) or in person kilometers (pkm). The

transport service refers to the distance covered in the respective territory.

*Purchase and sale of emission certificates. Reproduced with permission from [9].*

is around 15% in aviation and 2% in rail transport, respectively [4].

impact on the transport sector in future [18].

transport performance provided.

The steady growth of online commerce has and will continue to have a major

Large online mail order companies promote the digitization of trade and thus the amount of goods that have to be transported to the end users. In Germany alone, freight traffic has risen by about 120% since 1990 [19]. Thus, the traffic volume takes up about 26% of the traffic-related energy consumption [20]. The strongest increase is recorded in road and rail transport. For the transport sector, energy intensity indicators are collected on the basis of energy consumption and the

These energy intensity indicators are used as a statistical measure of energy efficiency. In order to support the sustainable development of economic and livelihood models, indicators in the transport sector should include resource efficiency. Due to the large increase in freight traffic in recent years, the objective within freight transport should be to decouple growth in terms of increased transport performance and CO2 emissions. Energy consumption in freight transport related to rail and aviation

Overall, it can be summarized that the energy consumption has increased less than the transport performance. Thus, it can be concluded that energy efficiency in freight transport has increased, but growth is neutralizing the efficiency gains

As it can be seen in **Figure 3**, aviation has the highest specific energy consumption. Low oil prices encourage the (continued) use of older, less energy-efficient cargo aircraft, making them economically viable again or extending their useful

**116**

achieved [4].

*Development of specific energy consumption in freight traffic by mode of transport from 1995 to 2013 (modified from [21], p. 246).*

lifetime. This could have an impact on indicator development. In the second place is the use of trucks, which are logistically almost inevitable due to the infrastructure in most countries, particularly for "last mile" delivery.
