Energy is perhaps one of the most focused upon areas of our economy. With fears of peak oil and fossil-fuel produced global warming there is increasing consensus that we must look to reduce and offset our energy usage. Vehicles like the Tesla offer better energy efficiency, but still involve over 2,000 kilos of metal moving – often just for one person. Transit, by bus or train offers far greater energy efficiency.
Worldwide 98% of transport relies on oil, but in Japan this figure is slashed to 61%, still a long way from oil free, but a significant burden removed from an economy with little to no natural reserves of fossil fuels. Japan’s secret? Railways. Steel wheels and long vehicles offer far more efficient transportation, even at much greater speeds.
Not only can trains run directly off grid electricity, allowing the use of renewable generation or at least more efficient land based combustion plants, they’re incredibly efficient compared to their rubber wheeled counterparts. A modern, fully loaded Shinkansen Train uses about 25Wh per passenger km (one passenger carried 1 kilometer) – a well loaded road car (4 people, 6L/km) uses over 125Wh to do the same. Shifting to typical passenger loadings rail only does better, with the French TGV Atlantique using 7 times less energy than a typically loaded car (1.5 passengers).
Freight is perhaps more important than passengers. Our modern freight ecosystem typically involves shipping products around the world to consumers (often multiple times). So any improvements here can offer big savings.
For this data we’re looking at kJ per tonne km – that is the energy (in kilojoules) required to move 1 tonne 1 kilometer, 1 Wh is roughly 3.6kJ.
Air freight (6,900kJ/tonne-km) is unsurprisingly inefficient – thus why it’s mostly used only for small time sensitive, high value deliveries. Heavy trucking is still very inefficient, at 2426 kJ/tonne-km – despite the US’ vast interstate system. Finally domestic waterborne (160kJ/tonne-km) is the most efficient, pulling in just under main rail corridors (209kJ/tonne-km). Water transport is definitely a winner on the seaside, although rising fuel prices could make electrified rail more sensible in the future, however over land, where usable water corridors are few and far in between, rail is a great mode of transport.
What’s being highlighted here is just how much energy an efficient transportation system can save. In many cases, not only is rail faster, it’s also more energy efficient than “traditional” modes of transport.
Historical US Petrol Data: US Energy Information Administration
Passenger Transport Information:
- US Transport Book
- US Government Fuel Efficiency Data
- Wikipedia’s Energy Density Information
- Japan Railway and Transport Review