[Big Dave]

Trains are indeed more fuel efficient than trucks. Look at one from the air...it approximates the shape of a spear. Add to that the rolling resistance is the same as a rubber tire on polished glare ice. Railroads are generally laid out along water grade. There is still a bit of track at over 2% grade but there ain't much. Even the UP's Sherman Hill grade and CSX' Cheviot Hill got bypassed.

A train will generally reach what railroaders call the "ruling grade" (a combination of steepness and length) and when the train tops that grade, the engineer can coast the rest of the way to the next stop. Quite often they will top the ruling grade and have to immediately go into dynamic braking.

Another advantage of railroads is that the amount of mainline track (where most of the energy is used) is down to about 10,000 miles. We are reaching the point where mainlines could be electrified. Electrification is well-proven old tech. Electrification allows railroads to free themselves (for mainline use at least) of oi and they could use electricity which in the US is mostly generated by coal or nuclear power. Speaking of dynamic braking, an electrified line can recycle about 85% of the energy needed to climb a hill. When a trian reaches the top of the hill, a dispatcher holds the train until another train starts up the hill. The train at the top of the hill is released and goes into dynamic braking and feeding the electricity back into the catenary, where the climbing train can use it. Very efficient.

Drawbacks of electrification: High capital cost. $10 million a mile on average. Railroads run at nearly right angles to high-voltage transmission lines. Lots of new high-voltage rights of way will be needed. Catenary electrification is butt ugly. The US does not have enough excess electricity to run electric mainline operations.