deferred maintenance has resulted in serious structural failures (IWUB, 2005). The IWUB identified approximately 20 construction and rehabilitation projects that it believes are critical to the inland waterways systems, with a total price tag to completion of more than $5.4 billion. This would require an annual expenditure of $477 million, about $100 million above the FY 2006 actual appropriation. However, this level of expenditure would not be sustainable with the current trust fund balance and expected future income (IWUB, 2005). Fund income has averaged about $100 million per year over its history, and it would be required to contribute $2.7 billion as its share of the $5.4 billion called for by the IWUB.

TRANSPORTATION OF COAL EXPORTS AND IMPORTS

Exports of coal from the United States are currently around 50 million tons, a little less than half of the record export tonnages transported in the 1980s. Exports are expected to decrease in the future, primarily due to the anticipated availability of low-cost coal supplies from South America, Asia, and Australia (EIA, 2006d). In fact, the EIA reference scenario predicts that the U.S. share of the total world coal trade will fall from 6 percent in 2003 to 3 percent in 2025. At the same time, U.S. imports of low-sulfur coal are projected to grow, from the current 28 million tons to almost 90 million tons by the year 2030. The potential need to meet tighter emissions targets may make coal imports an attractive option for coal-fired power plants in the Gulf Coast and Atlantic seaboard areas (EIA, 2006d).

The national transportation network is not expected to be challenged by these predicted export and import trends. Transloading terminals on the Gulf Coast and the Atlantic seaboard have adequate capabilities for managing such traffic, and they have managed increased volumes in the past. However, reversing or shifting the flow direction from export to import may present logistical and operational problems for the transportation infrastructure, principally the railroads.

ELECTRICITY TRANSMISSION

Constraints on the delivery of electricity from power plants can reduce the natural competitive advantage that coal-fired power plants have over plants fueled by oil or natural gas that cannot generate electricity as cheaply. Consequently, transmission constraints have the potential to limit future coal use. Coal’s competitive advantage relies on “economic dispatch”2 that theoretically operates in the electricity generation market (DOE, 2005). However, in practice

2

Every power plant has a schedule of production levels and costs. In theory, units are called upon to provide power in “merit order,” in which the least expensive units are dispatched first, with additional units being dispatched in order of increasing costs until electricity needs are met. Factors that could increase the production costs of coal-based plants and thereby alter dispatch order, such as environmental constraints, are discussed in Chapter 6.



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