Energy Efficiency Demonstration Residential Ductless Heat Pumps (DHP) Overview Ammi Amarnath Chris Trueblood 22 February 2010
Energy Efficiency Demonstration DHP: Overview Research Objectives Assess residential ductless heat pump technology by measuring its performance and efficiency Assess installation and operation in a field demonstration setting Assess occupant satisfaction and comfort 2
Energy Efficiency Demonstration DHP: Technology Background and Benefits Non-ducted, split system heat pumps Also known as mini- and multi-splits Developed in Japan as quieter, more efficient alternative to window units Space conditioning provided by distributing cooled and heated refrigerant through a network of refrigerant lines One outdoor unit connects to 1 or more (typically up to 4) fan-coil indoor units Systems often include: variable-speed fans variable-capacity compressors wireless controls 3
Energy Efficiency Demonstration DHP: Technology Background and Benefits Component options: one outdoor unit connects up to four indoor units Outdoor Unit Typical rated capacities: 0.75 ton to 4.0 ton Requires short ductwork Most popular indoor unit style 4
Energy Efficiency Demonstration DHP: Technology Background and Benefits Compared to conventional ducted unitary split systems Air duct losses are minimized or eliminated Can improve system efficiency 10% or more Inverter driven variable speed compressor and fan systems Operates continuously Matches partial load conditions Eliminates compressor cycling Efficiency ratings, up to: 25.0 SEER 14.5 EER 12.0 HSPF 5
Energy Efficiency Demonstration DHP: Technology Background and Benefits Improved comfort Each indoor unit has its own thermostat Multiple cooling/heating zones Improved humidity control (some units actively control humidity) Lower noise, both indoors and outdoors Typically easier installation Often favorable for retrofit applications Anticipated retail cost Typically $1,200 to $1,800 per rated ton for variable-speed DHP equipment, per system Installation varies widely from about $1,500 to more than $4,000 depending on layout 6
Energy Efficiency Demonstration DHP: Technology Equipment and Manufacturers Products Mitsubishi Ready to Deliver Mr. Slim ductless and short-duct LG Ready to deliver Art Cool ductless and short-duct Daikin Ready to deliver Quaternity ductless Fujitsu Ready to deliver Halycon ductless 7
Energy Efficiency Demonstration DHP: Demonstration Instrumentation Instrumentation Package Options for Field Measurements Lite package Energy and power for: (1) HVAC equipment and (2) whole house Full package adds Basic power quality data (volts, amps, VARs, and freq) Outdoor temperature, relative humidity Indoor temperature, up to 4 zones Refrigerant temperature on main lines, within outdoor unit COP package adds Airflow rate* Return air temperature, relative humidity* Supply air temperature, relative humidity* * At this time, COP package is considered for installations only with short-ducted indoor units 8
Energy Efficiency Demonstration DHP: Demonstration Instrumentation Data collection framework: full package Same approach for all packages 9
Energy Efficiency Demonstration DHP: Demonstration Instrumentation Network interface options 1 Ethernet Cable Network Switch (Gateway) 1 Ethernet Cable WiFi Access Point IEEE 802.11g WiFi Access Point Network Switch (Gateway) Internet EPRI Server 1 Ethernet Cable Cellular Modem GSM/GPRS Cellular Network 10
Energy Efficiency Demonstration DHP: Demonstration Instrumentation Full package: installation in a house 11
Energy Efficiency Demonstration: DHP Full Instrumentation Package Data Acquisition Panel: 24 wide, 14 tall Whole house power meter (with 2 split CTs) Refrigerant temp sensors (x2) Wireless base station (plugs into home router) Wireless indoor temp and humidity sensors (up to 4 per site) HVAC power meter (with 2 solid CTs) Not shown: outdoor temperature and humidity sensor 12
Energy Efficiency Demonstration DHP: Demonstration Site Selection Criteria All sites Owned by occupants Same family till end of project Standard utility rates Indoor wall space for instrumentation Pairing treatment/control sites Nearly identical dwellings Nearly identical historical energy consumption Treatment sites: new new DHP DHP Appropriate layout, floor plan plan Up Up to to 44 indoor indoor units units Up Up to to 55 ton ton total total capacity capacity Offsets all all existing HVAC Adequate physical space for for indoor/outdoor units Access to to install line-sets and and electrical service Control sites: existing HVAC Only Only one one system operating System tuned-up, meets code 13
Energy Efficiency Demonstration DHP: Demonstration Field Test Plan Overview Scope to include both heating and cooling modes, per host utility request Emphasis on right-sized and right-fitted residential applications Participant sites Treatment: provided with new DHP system 20 per host utility Ideally all 20 instrumented (minimum 10) Offsets entire existing HVAC system Control: existing HVAC system monitored Ideally 5 instrumented (minimum 2) per host utility Provides baseline for side-by-side comparison with treatments 14
Energy Efficiency Demonstration DHP: Demonstration Field Test Procedure Overview All sites monitored in parallel, up to 2 years Treatment sites All existing space conditioning systems disabled during demonstration Occupants instructed to operate DHP system normally, year-round for both heating and cooling seasons Control sites Occupants instructed to operate existing space conditioning systems normally, yearround for both heating and cooling seasons 15
Energy Efficiency Demonstration DHP: Demonstration Data Collection and Surveys Automated Data Acquisition Minimal intrusiveness to occupants Sample (or averaged) every 1-minute Daily uploads to EPRI, via internet Surveys For treatment sites only Occupants observations Before DHP installation After each cooling/heating season (twice per year) Installers experiences, comments after DHP installation 16
Together Shaping the Future of Electricity 17