Conserving energy in transportation

The transportation sector is responsible for an average of one third of the total energy demand in the majority of countries, including industrialized and developing countries. It also keeps increasing its share, while other sectors are reducing or maintaining their share in the total energy demand.

When comparing energy intensities (energy/ton-km or energy/passenger-km) among transport modes, it becomes clear that modal shift (e.g., from road to rail) is an important way of reducing energy consumption and still meeting the transport demand. However, energy accounting alone should not be used as the sole basis for determining the preferability of one mode over another, since each mode provides different services in terms of access, flexibility, convenience, time in transit, comfort, relative costs, safety etc. Also, an analysis of comparative energy intensities alone does not reveal the total energy actually used in a particular mode. Several components have to be considered for a thorough evaluation of potential transportation energy savings, including not only propulsion energy, but also energy to operate stations and other infrastructure, maintenance, energy to construct rights-of-way and manufacture vehicles, among others. Nevertheless, if the simplest analysis were made, then energy intensities of passenger transport modes, from highest to lowest, in general terms are: air, private automobile, urban mass transit, rail (local trains) and bus. For freight transport modes, energy intensities, from highest to lowest, are: air, road (trucks), rail, waterways and pipeline. It is recommended that countries explore possibilities for urban transport such as express bus lanes and mass transit systems, including light rail and metro service.

Besides modal shifts, there are several other ways to improve energy efficiency in transport. Increased efficiencies in transport equipment (vehicles, engines), increased load factor and improved usage patterns are among the main ways to conserve energy. In this regard, it is recommended that countries institute driver-training and vehicle-maintenance programmes.

Reduction in transport demand can also be achieved via improved telecommunications, better land-use patterns and adequate transportation planning. In terms of policy approaches, two basic options exist: direct co mm and and control (through regulation, administrative fiat, physical constraints) and indirect control (through fiscal measures), depending on whether market prices alone may secure the desired modifications. Examples of these two options include licensing schemes and road pricing or toll collection.