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A mental exercise on freight train efficiency
Author: Chris
Date: 02-15-2007 - 14:32
I just did a little mental exercise in the car on the way home and wanted to get some comment.
According to a program I saw on TV last week, the average truck engine puts out 300-400 horsepower. An SD70-series locomotive puts out 4000-4300 horsepower.
Let's assume the following hypothetical. Give the benefit of the doubt to the truck and put a 400-horse engine in the truck, and go with the 4000 hp motor in the locomotive. A typical 100-car tank train has 4 SD70MAC motors. According to one railroad official, a tank car holds approximately three tanker trucks' worth of fuel.
So, the train is hauling 300 tanker trucks worth of fuel and has 40 times as much horespower (4,000 x 4 = 16,000, and 16,000 / 400 = 40.
Now, 300 tanks / 40 times more horsepower equals 7.5. Does that mean that hauling a commodity by rail is 7.5 times as fuel-efficient as hauling it by truck?
I know rail is more efficient, but is it that big of a difference?
According to a program I saw on TV last week, the average truck engine puts out 300-400 horsepower. An SD70-series locomotive puts out 4000-4300 horsepower.
Let's assume the following hypothetical. Give the benefit of the doubt to the truck and put a 400-horse engine in the truck, and go with the 4000 hp motor in the locomotive. A typical 100-car tank train has 4 SD70MAC motors. According to one railroad official, a tank car holds approximately three tanker trucks' worth of fuel.
So, the train is hauling 300 tanker trucks worth of fuel and has 40 times as much horespower (4,000 x 4 = 16,000, and 16,000 / 400 = 40.
Now, 300 tanks / 40 times more horsepower equals 7.5. Does that mean that hauling a commodity by rail is 7.5 times as fuel-efficient as hauling it by truck?
I know rail is more efficient, but is it that big of a difference?
A mental exercise on freight train efficiency