District energy networks are very common in dense downtown areas and at colleges and universities. They are also often found at medical campuses, military bases, office parks, convention centers, sports arenas, airports, sustainable housing developments, or other clusters of buildings. These systems combine of a combination of electricity generation, steam, heating, or cooling at a central plant and distribute that energy to a network of nearby buildings.
Individual buildings connected to the district system avoid the need to install and maintain their own boilers, furnaces, chillers, or air conditioners, saving on capital and maintenance costs. A central plant serving steady, even loads is more efficient than individual building heating and cooling systems that have to ramp up or down to meet the building’s needs.
Many district energy schemes use combined heat and power, recycling the thermal energy left over from electricity generation for heating or cooling. District energy systems can use a variety of conventional fuels such as natural gas, coal, or oil—whichever fuel is most competitive at the time. Many district energy systems are transitioning to all or partial use of a local resource such as renewable biomass or landfill gas.
Through the Southeast Clean Energy Application Center program, the N.C. Solar Center provides District Energy information, educational events, news and site assessments.