Environmental and Energy Study Institute (EESI)

On September 23, 2011, the Environmental and Energy Study Institute (EESI) held a briefing on an under-appreciated yet essential part of many communities’ infrastructure: district energy. District energy systems distribute thermal energy (steam, hot water, and/or chilled water) through a network of underground pipes to multiple buildings in an area, such as a downtown district, college or hospital campus, airport, or military base. By aggregating the heating and air conditioning supply for multiple buildings, district energy systems optimize thermal energy efficiency. They also achieve economies of scale that allow for the use of low-carbon, cost-effective thermal energy sources – such as the “waste” heat from power plants or industrial processes, combined heat and power, geothermal energy, deep lake water, or municipal solid waste and other types of biomass – that may not be feasible for individual buildings. At this briefing, district energy experts provided an overview of the technology and discussed case studies where district energy reduced operating costs, created jobs, strengthened grid reliability, reduced emissions, and converted waste streams into useful thermal energy. Speakers for this event included: