At least three people have questioned whether using wood for locomotive fuel will cause all the forests to be cut down.
My first reaction has been "NO, NO, NO! I only want A FEW steam locomotives in service...bridging the gap until a better technology, such as electric trains, is installed and available, and after that in use for special applications."
But since several people are obviously worried already, I have done a "what-if" scenario that gets some perspective on the problem and should provide some reassurance.
I took numbers from the 2005 Burlington Northern Santa Fe Railway Annual Report to estimate the land area required to sustainably run a steam railroad. If you are affiliated with the BNSF, sorry. This is only for illustration. I don't expect you to go out and do this.
In 2005 the BNSF had 31,000 route miles and used 1,402 million gallons of diesel fuel. If we assume that steam locomotives are 1/4 the efficiency of diesel (eg. 7% vs 28%) then that would be 5,608 million gallons or about 39,256 million pounds of fuel, which is 19.6 million tons. Since wood has about 1/3 the heat value per pound than diesel fuel, that would be 58.8 million tons of wood. Assuming 2700 dry lb wood/cord, that would be 43.5 million cords. Using a sustainable 1 cord/ acre per year (this is a wood lot that is only thinned occasionally) we get 43.5 million acres, or 68,000 square miles.
Now that is a lot of land- bigger than Oregon. But this scenario involves the second biggest railroad in the country. If we divide the square miles by the route miles we get 1.9 miles. So if the BNSF planted a mile of forest on each side of the right-of-way, they could keep the railroad going with steam locomotives indefinitely!
Of course, that wouldn't work, for various reasons. For instance, much of the USA is not suitable for growing trees, and the land is being used for other things, etc. But the point is that in forested areas a swath of land along the track could be used to sustainably grow wood for locomotive fuel, without destroying all the forests.
It is interesting to look at the money that the BNSF spent on fuel in 2005, and compare that to the cords of wood equivalent. $1,959 million for 43.5 million cords is $45/cord that the railroad could pay and break even. A modern engine would be using stoker-fired briquettes, which would be far less cost to produce than cordwood. So maybe we are near the break-even point right now.
Copyright © 2007 Charles Turner