Our project is a new 8,700 square foot building to house pets awaiting adoption. Space for administrative functions and animal treatment is included in the new facility. Additional floor space was provided in the building for future use. A nominal 45-ton closed loop geothermal heat pump (GHP) system was installed to provide space heating and cooling capacity. This system consists of two water-to-water heat pumps connected to a vertical ground loop heat exchanger. These heat pumps supply either hot or chilled water to dual temperature coils in four air handling units. The two air handling units serving the animal wings are variable air volume. Manual switches have been provided to electrically open and close zone dampers in the animal housing area depending on space occupancy. Both air handling units are equipped with variable speed drives to vary supply and exhaust air flow in response to a duct static pressure control. These units also include plate type heat exchangers to pre-heat or pre-cool 100% outdoor air before it is conditioned by the hot or chilled water supplied by the heat pumps. Constant volume units serve the lobby and administration area. When outside weather conditions permit, two large sliding doors in the lobby can be opened to provide natural ventilation. These doors are interlocked through a control system to shut down the lobby air handling unit when either door is open. Gas duct heaters are installed upstream of all four air handling units to temper outdoor air (to about 40
Utility and municipal efficiency programs/protocols, including ASHRAE 90.1, do not allow a comparison between a baseline water-source system and an air source system. Due to different system characteristics and performance efficiencies, there is potential for the estimated energy savings to become skewed and overstated. This is also the case when trying to compare an electric resistant heat to gas fired heat sources. Again, the differential cost between these fuel sources can artificially inflate the Energy Cost Budget (ECB), dependant on which fuel source is modeled. Since ASHRAE 90.1-1999 is the credit\'s reference standard, then its modeling guidelines and protocols should be followed unless the local code is more stringent. Applicable internationally.