Coal-fired steam engines powered the industrial revolution. Steam locomotives pulling cars were the first high speed land transportation. In fact, steam locomotives were used on mainline railroads in the United States until 1960 (http://en.wikipedia.org/wiki/Steam_locomotive). Big steam locomotives could generate more horsepower than diesel-electric locomotives, but required more refueling and maintenance. On the sea, everyone is aware of the transition from the great sailing ships on the oceans to steamships. Those too have been supplanted by diesel/bunker fuel propulsion.
It’s hard to see civilization as we know it functioning on coal as it’s primary transportation fuel again. Coal is a messy, inconvenient poor relation to oil for moving vehicles around. Coal has a lower energy density and generates more CO2 for the same of amount of energy produced It’s hard work to dig it out of the ground and harder to transport than oil. It doesn’t flow. It’s plant material compressed into a combustible rock after all. While coal works quite well for generating electricity in big coal-fired plants, can you imagine using a trunk full of coal to heat a boiler to produce steam to move your car? I suspect not. We will certainly see coal-generated electricity charging batteries for vehicles like the Chevy Volt, but the Volt’s 40 mile range with a huge $8,000-10,000 battery and overall $41,000 price is pretty inferior to the range and current cost of a conventional economy gas or diesel vehicle.
Like oil or gas, there is only a finite amount of coal in the crust of the Earth. The U.S. Energy Information Administration claims there are an estimated 929 billion tons (2000 lb)of recoverable coal. Expressed in metric tons (1000 kg), the World Coal Institute reports estimates of proven reserves at 847 billion tonnes. Here’s their chart of relative distribution–
This sounds like quite a bit, but worldwide consumption is over 6 billion tonnes per year. If we could somehow make up the decline in oil with coal, that consumption rate would need to more than double. Like oil or gas, there is likely to be a production peak in a coal-producing region, then a decline. Wikipedia has an article on this in which it is claimed that the peak energy production from coal was reached in the U.S. in 1998. There are harder and softer coals. The harder coals have more energy when burned. The U.S. is producing more total coal, but more of it is the softer, lower energy content varieties.
It occurs to me that as oil production declines, coal production might actually decline rather than grow. Petroleum-powered machines plan a big role in mechanized coal production and transport. In addition, if the economy is shrinking as a result of oil production decline, demand for coal could actually decline.