The world energy crisis and global warming call for a reduction of energy consumption. High speed rail, increasingly viewed as an effective solution to inter-city passenger transportation challenge of the 21st century, has the significant ability of increasing passenger capacity and reducing journey time. The advent of high speed rail provided many research opportunities. So far studies have been contributed from different perspectives: economical, environmental, and technical. The main research gaps are: addressing the problem of the effects of route geometry on train energy consumption and quantifying the contributing factors towards differences in energy consumption between different types of high speed trains. In addition, this energy ...