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The impact on space conditioning energy use due to operating a heat pump water heater (HPWH) inside the conditioned space is analyzed based on 2010-2011 data from a research house with simulated occupancy and hot water use controls. The 2700 ft² (251 m²) house is located in Oak Ridge, TN (mixed-humid climate) and is equipped with a 50 gallon (189 L) HPWH that provided approximately 55 gallons/d (208 L/d) of hot water at 120°F (48.9°C) to the house during the test period. The HPWH has been operated every other week from December 2010 through November 2011 in two modes; a heat pump only mode, and a standard mode that utilizes 15355 Btu/h (4500 W) resistance heating elements. The energy consumption of the air-source heat pump (ASHP) that provides space conditioning for the house is compared for the two HPWH operating modes with weather effects taken into account. Impacts during the heating and cooling seasons are compared. [ABSTRACT FROM AUTHOR]

In this paper we present measured performance and efficiency metrics of Ground Source Heat Pumps (GSHPs) for space conditioning and for water heating connected to a horizontal ground heat exchanger (GHX) loop. The units were installed in a 345 m² (3700 ft²) high-efficiency test house built with structural insulated panels (SIPs), operated under simulated occupancy conditions, and located in Oak Ridge, Tennessee (USA) in US Climate Zone 4 . The paper describes distinctive features of the building envelope, ground loop, and equipment, and provides detailed monthly performance of the GSHP system. Space conditioning needs of the house were satisfied by a nominal 2-ton (7.0 kW) water-to-air GSHP (WA-GSHP) unit with almost no auxiliary (resistance) heat usage. Recommendations for further improvement through engineering design changes are identified. The comprehensive set of data and analyses demonstrate the feasibility and practicality of GSHPs in residential applications and their potential to help achieve source energy and greenhouse gas emission reduction targets set under the IECC 2012 Standard. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive simulation model for advanced membrane-based heat and mass exchanger (HMX) components which account for three separate fluid streams with complex flow patterns. The model was implemented with various liquid desiccants and their properties (including LiCl, CaCl and ionic liquid (IL)). Preliminary model validation is presented using data from a laboratory prototype absorber. The paper also presents implementation of the model into a sorption system modeling platform and analyzes potential benefit analysis of the HMX component in utilizing the sensible and latent heat removed in space cooling to heat water. The developed model and codes are expected to enable detailed optimization studies and identify novel configurations for the three-fluid HMX maximum performance and cost effectiveness. [ABSTRACT FROM AUTHOR]

We developed a detailed steady-state system model, to simulate the performance of an integrated five-zone Variable Refrigerant Flow (VRF)heat pump system. The system is multi-functional, capable of space cooling, space heating, combined space cooling and water heating, and dedicated water heating. Methods were developed to map the VRF performance in each mode, based on the data produced by the equipment system model. The performance maps were used in TRNSYS annual energy simulations. Using TRNSYS, we have successfully setup and run cases for a multiple-split, VRF heat pump and dehumidifier combination in 5-zone houses in 5 climates that control indoor dry-bulb temperature and relative humidity. We compared the calculated energy consumptions for the VRF heat pump against that of a baseline central air source heat pump, coupled with electric water heating and standalone dehumidifiers. In addition, we investigated multiple control scenarios for the VRF heat pump, i.e. on/off control, variable indoor air flow rate, and using different zone temperature setting schedules, etc. The energy savings for the multiple scenarios were assessed. [ABSTRACT FROM AUTHOR]