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Advanced Controls for Ground-Source Heat Pump Systems

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Advanced Controls for Ground-Source Heat Pump Systems ORNL/TM-2017/302 CRADA/NFE-13-04586 Advanced Controls for Ground-Source Heat Pump Systems Xiaobing Liu Patrick Hughes Anthony Gehl Shawn Hern (formerly ClimateMaster) CRADA final report for Dan Ellis (formerly CRADA number NFE-13-04586 ClimateMaster) Approved for public release. Distribution is unlimited. June 2017 DOCUMENT AVAILABILITY Reports produced after January 1, 1996, are generally available free via US Department of Energy (DOE) SciTech Connect. Website http://www.osti.gov/scitech/ Reports produced before January 1, 1996, may be purchased by members of the public from the following source: National Technical Information Service 5285 Port Royal Road Springfield, VA 22161 Telephone 703-605-6000 (1-800-553-6847) TDD 703-487-4639 Fax 703-605-6900 E-mail [email protected] Website http://www.ntis.gov/help/ordermethods.aspx Reports are available to DOE employees, DOE contractors, Energy Technology Data Exchange representatives, and International Nuclear Information System representatives from the following source: Office of Scientific and Technical Information PO Box 62 Oak Ridge, TN 37831 Telephone 865-576-8401 Fax 865-576-5728 E-mail [email protected] Website http://www.osti.gov/contact.html This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. ORNL/TM-2017/302 CRADA/NFE-13-04586 Energy and Transportation Science Division Advanced Controls for Ground-Source Heat Pump Systems Xiaobing Liu Patrick Hughes Anthony Gehl Shawn Hern (formerly ClimateMaster) Dan Ellis (formerly ClimateMaster) Date Published: June 2017 Prepared by OAK RIDGE NATIONAL LABORATORY Oak Ridge, Tennessee 37831-6283 managed by UT-BATTELLE, LLC for the US DEPARTMENT OF ENERGY under contract DE-AC05-00OR22725 Approved for Public Release iii TABLE OF CONTENTS LIST OF FIGURES ..................................................................................................................................... iv LIST OF TABLES ....................................................................................................................................... iv ACRONYMS .............................................................................................................................................. vii ABSTRACT .................................................................................................................................................. 1 1. STATEMENT OF OBJECTIVES ........................................................................................................ 2 2. BENEFITS TO THE FUNDING DOE OFFICE'S MISSION ............................................................. 2 3. TECHNICAL DISCUSSION OF WORK PERFORMED BY ALL PARTIES ................................... 3 3.1 A FIRST-OF-ITS-KIND FLEXIBLE RESEARCH PLATFORM FOR DGSHP SYSTEMS .................................................................................................................................. 3 3.1.1 Overview ........................................................................................................................ 3 3.1.2 Ground Source Emulator ............................................................................................... 3 3.1.3 Experimental DGSHP System ....................................................................................... 6 3.1.4 Data Acquisition System .............................................................................................. 10 3.1.5 Research Capability ..................................................................................................... 11 3.2 SMART WATER HEATING CONTROL FOR GS-IHP ........................................................ 11 3.2.1 Background and Introduction ...................................................................................... 11 3.2.2 Apparatus for Water Heating Test ............................................................................... 12 3.2.3 Water Heating Performance with Existing Control ..................................................... 14 3.2.4 New Controls ............................................................................................................... 18 3.2.5 Conclusions and Recommendations ............................................................................ 22 3.3 SMART PUMPING CONTROL .............................................................................................. 23 3.3.1 Background and Introduction ...................................................................................... 23 3.3.2 Simulation-based Study ............................................................................................... 24 3.3.3 Experimental Tests ....................................................................................................... 25 3.3.4 Conclusions and Recommendations ............................................................................ 31 4. SUBJECT INVENTIONS .................................................................................................................. 32 5. COMMERCIALIZATION POSSIBILITIES ..................................................................................... 33 6. PLANS FOR FUTURE COLLABORATION.................................................................................... 33 7. CONCLUSIONS ................................................................................................................................ 33 REFERENCES ........................................................................................................................................... 35 iii LIST OF FIGURES Figure 1. The building hosting the flexible DGSHP system test facility. ..................................................... 4 Figure 2. Diagram of the DGSHP test facility. ............................................................................................. 4 Figure 3. The ground source emulator. ......................................................................................................... 5 Figure 4. A control diagram of the ground source emulator. ........................................................................ 5 Figure 5. A screenshot of the control panel of the ground source emulator. ................................................ 6 Figure 6. Heat pumps, water tank, and hot water draw simulator. ............................................................... 7 Figure 7. Layout of heat pump, ductwork, and pipeline at (a) first floor and (b) second floor. ................... 8 Figure 8. Equipment of a central variable-speed pumping system. .............................................................. 9 Figure 9. Apparatus for evaluating water heating performance of GS-IHP................................................ 13 Figure 10. Piping connections and data collection points for the water tank. ............................................. 14 Figure 11. Comparison between the dedicated heat pump water heating with the GS-IHP (HP205) and the electric element water heating (HP105). ..................................................................... 15 Figure 12. Comparison of daily accumulative electricity consumption between the dedicated heat pump water heating and electric element water heating. ......................................................... 16 Figure 13. Comparison of water tank temperatures resulting from different water heating operations: (a) dedicated heat pump water heating and (b) electric element water heating. .................................................................................................................................... 17 Figure 14. An example of GS-IHP operation with existing controls: (a) power consumption and (b) average tank temperature and combined COP of simultaneous space cooling and water heating. .................................................................................................................................... 17 Figure 15. Ground source temperature when GS-IHP was operated with new control (tested on 7/29/2015). .............................................................................................................................. 19 Figure 16. Power consumption of GS-IHP resulting from two different controls. ..................................... 19 Figure 17. Performance of GS-IHP with 120°F tank temperature set point. .............................................. 20 Figure 18. Performance of GS-IHP with 130°F tank temperature set point. .............................................. 21 Figure 19. Performance of GS-IHP with 130°F tank temperature set point. .............................................. 22 Figure 20. Configuration of a typical DGSHP system with a central pump controlled to maintain (a)
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