benefits, but also some risks, writes Worldwatch Institute Senior Researcher Michael Renner in the Institute's latest Vital Signs Online report. In 2013, people traveled an estimated 2,865 billion passenger-kilometers by intercity rail. Freight rail movements amounted to some 9,789 billion ton-kilometers worldwide.
The world's rail vehicle stock ran to almost 3 million locomotives, railcars, and coaches. Rail transport offers an energy-efficient way to move people and goods. Although different transportation modes are difficult to compare, available estimates indicate that rail transport generally requires less fuel than movement by road vehicles.
In the United States, intercity rail in 2012 required 78 percent of the energy (2,481 British thermal units, or Btu) per passenger mile required by cars (3,193 Btu). However, rail transport also brings challenges. Freight trains have long helped to maintain the resource-intensive global economy by moving raw materials from countries' interiors to export terminals. And other negative impacts are growing with the expansion of rail transport.
Rail is being used increasingly to move oil, for example, causing dangers of spills and explosions. In 2013, train shipments resulted in 117 oil spills in the United States, representing a nearly 10-fold increase over 2008. This year, a derailment in the U.S. state of Virginia caused a spill of 114,000 liters (30,000 gallons) of crude oil into a river. In Quebec, Canada, a derailment in 2013 led to an explosion that killed 47 people. Improved energy efficiencies and other smart choices can help to maximize positive impacts as rail systems grow.
Electrification of rail lines, for example, offers a number of advantages, including higher energy efficiency. Worldwide, 28 percent of rail lines are electrified, but the percentage varies enormously among individual countries-from as high as 100 percent of rail lines in Switzerland to as low as 2 percent in Indonesia.
The energy efficiency of freight rail vehicles has also increased massively, reducing by more than half the amount of energy required to haul one ton of freight over one kilometer (from 1,112 Btu in 1970 to 473 Btu in 2012 in the United States) as vehicle capacity increases.
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