Energy and Exergy Analyses of District Heating and Cooling Systems for Improvements in Sustainability and Performance

摘要

To advance long-term sustainability at the University of Idaho (UI) energy plant, energy and exergy losses are quantified and equipment improvements are prioritized accordingly. Emissions from biomass and natural gas are compared to show the impact of moisture content in the biomass versus the heating value of the biomass. The pressure reducing valve (PRV) restricts potential improvements from adjusting steam pressure, however replacing the PRV with a steam turbine results in increased system energy and exergy efficiencies while providing economic benefits by generating electricity. Utilizing waste to energy technology at UI energy plant provides opportunity to use municipal solid waste (MSW) as fuel and reduces the regional environmental impacts from waste on soil, water, and air while saving the landfills.