Energy consumption and greenhouse gas emissions from commercial and manufacturing sectors Specific studies on HVAC equipment and dairy processing

Commercial and manufacturing sectors in United States consumed approximately 50% of the total End use energy in 2010. In 2009, 81.5% of the greenhouse gas (GHG) emitted in the United States was energy related. From the broad aspects of commercial and manufacturing sectors; two relatively narrow and specific topics, commercial building's HVAC equipment and dairy processing were chosen to increase the understanding of the energy use and GHG emission in these two sectors. Few published studies related to these two specific areas are available. The first study in this thesis discussed the energy use and GHG emissions by HVAC equipment in commercial buildings. The second study in this thesis discussed the energy use and GHG emissions of dairy processing plant with 4 production sequences, fluid milk, cream, whey and cottage cheese. The mass and energy balance of each individual unit operation in the sequence were studied and the total GHG emissions per unit of final product were found. Compared to natural gas (NG) use, the GHG emission from electricity use by commercial building's HVAC equipment is dominant. Furthermore, energy use and GHG emissions were also influenced by these factors, source emission factors, climate, building specifications, HVAC capacity and building location geographical influence. NG based unit operation in dairy processing plant were found to be the largest GHG emitter. The studies found component-level study is critical and necessary to better understand fossil fuel based energy use and GHG emissions impact. GHG emissions due to inefficiencies at the electric power generation origins are magnified at consumer end.