A major new investment by Warren Buffet has turned attention to the freight rail industry. What travels by rail?
About 49% of rail freight is coal and another 2% is oil. About 10% consists of grain and grain products. Wood and paper account for 4%. About 10% of loads are non-petroleum chemicals. Stones, gravel, sand, clay and glass account for about 10% Most of the rest (13%) consists of other food products, metals and metal products, motor vehicles, waste and scrap materials. Many of these products aren't particularly time sensitive. Power plants, for example, stockpile huge amounts of coal at little cost. This allow them to be indifferent to modest delays in particular rail deliveries, so long as the average amount delivered over a period of months stays consistent.
Freight rail is very fuel efficient and cost efficient, and produces far fewer injuries that comparable freight trucking, but it is rather slow and isn't well integrated into the retail economy. For the most part, freight rail is moving raw materials that someone will turn into something else or be packaged later for retail sale.
Before we wax stary eyed about the possibilities of passenger rail, we should give serious consideration to how to improve freight rails as an alternative to long haul trucking. Simple innovations like more "passing lanes" for train cars, improved networks to facilitate intermodal transportation of shipping containers, better marketing by rail lines, and addressing the reputation rail has for not being on time would go a long way towards shifting freight from trucks to rail with minimal technological advances. This, in turn, could make a big dent in air pollution and our nation's reliance on oil.
Wider use of intermodal freight rail also paves the way for greater use of plug in electric commercial vehicles (which is a good thing to the extent we can find cleaner ways to generate electricity and multiple technologies to do that are maturing). The biggest weakness of plug in electric vehicles for long haul freight traffic is that limitations on battery technology limit the range of affordable vehicles, and the technology also requires a national network of compatible repowering stations. But, electric powered trucks designed to make short runs from freight rail cities to local warehouses and from local warehouses to local retail stores don't need much range and can repower from a single local facility designed to serve a fleet of vehicles. This kind of infrastructure can be built piecemeal, at a much lower cost, as the intermodal model proves that it can work. This approach also makes having consistent national standards for repowering vehicles unimportant. This approach makes it feasible even for different trucking firms in the same city to use incompatible technologies with no real ill effects.
Similarly, making intercity buses more attractive with existing technology is a more promising alternative to improving passenger transportation options than infrastructure intensive high speed rail lines, for the bulk of the United States that has fairly low population densities and good interstate highways already in place. Most of the barriers to widespread use of intercity buses are social and comfort driven, not technological. It is possible to make a bus pleasant and comfortable, but so far, most intercity bus service stalks the niche of truly marginal passengers who have no concern other than cost. Buses are far more fuel efficient and easier on road infrastructure and congestion than air travel or travel in personal vehicles, and are close to existing passenger rail in safety, speed and fuel efficiency (while being far cheaper to put in place and being far more flexible).
Freight rail and intercity buses aren't sexy. But, they are proven technologies that could significantly and fairly painlessly reduce U.S. oil dependency with minimal capital investments compare to the alternatives. Also, unlike a lot of other new energy technologies, they address the core energy and economic structure problem of the United States, which is petroleum dependence, rather than the only tenuously linked matter of overall energy efficiency.
Obviously, we should also be looking for less polluting ways of generating electricity (and of reducing electricity and natural gas consumption). The coal carried by rail, which is the dominant means of generating electricity and has almost no other use, poses far greater dangers to health and safety and the environment (including climate change) than most people realize. Also, we should obviously look for ways to make motor vehicles on roads more energy efficient. But, both of those changes require major infrastructure investments and less proven technology, so those changes will take longer to produce results than shifts to freight rail and interstate buses.