ABSTRACT
In the last few decades district heating systems have been widely used in a number of European countries using waste heat from electric generation or refuse incineration, as well as energy from primary sources such as geothermal wells or fossil fired boilers. The current world status of district heat utilization is summarized. Cost and implementation projections for district heating systems in the U.S. are discussed in comparison with existing modes of space conditioning and domestic water heating. A substantial fraction, i.e., up to ∼ one-half of the U.S. population could employ district heating systems using waste heat, with present population distribution patterns. U.S. energy usage would be reduced by an equivalent of ∼30% of current oil imports. Detailed analyses of a number of urban areas are used to formulate conceptual district energy supply systems, potential implementation levels, and projected energy costs. Important national ancillary economic and social benefits are described; and potential difficulties relating to the implementation of district heating systems in the U.S. are discussed. District heating systems appear very attractive for meeting future U.S. energy needs. The technology is well established. The cost/benefit yield is favorable, and the conservation potential is significant. District heating can be applied in urban and densely populated suburban areas. The remaining demand, in rural and low population density communities, appears to be better suited to other forms of system substitution.
