Experimental Measurements of Evacuated Enclosure Thermal Insulation Effectiveness for Vacuum Flat Plate Solar Thermal Collectors
Encapsulating the absorber of a flat plate solar thermal collector in vacuum by an enclosure that can be evacuated can result in a significant increase in collector performance and achievable operating temperatures. This is a result of the thermal insulation effectiveness of the vacuum layer surrounding the absorber, as less heat is lost during collector operation. This work describes experimental thermal insulation characterization tests of prototype vacuum flat plate solar thermal collectors that demonstrate the improvement in absorber heat loss coefficients. Furthermore, this work describes the selection and sizing of a getter, suitable for maintaining the vacuum inside the enclosure for the lifetime of the collector, which can be activated at low temperatures.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1124897Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 997
 R. Moss and S. Shire, “Design and performance of evacuated solar collector microchannel plates,” in EuroSun Conference, 2014.
 Kingspan Solar, “Thermomax FN.”
 F. Arya, T. Hyde, P. Henshall, P. Eames, R. Moss, and S. Shire, “Fabrication and characterisation of slim flat vacuum panels suitable for solar applications,” in EuroSun Conference, 2015, no. September 2014, pp. 16–19.
 F. Arya, T. Hyde, P. Henshall, P. Eames, R. Moss, and S. Shire, “Thermal analysis of flat evacuated glass enclosure for building integrated solar applications,” in Advanced Building Skins, 2015.
 C. B. Eaton and H. a. Blum, “The use of moderate vacuum environments as a means of increasing the collection efficiencies and operating temperatures of flat-plate solar collectors,” Sol. Energy, vol. 17, no. 3, pp. 151–158, 1975.
 Shire, G. S. F., R. W. Moss, P. Henshall, F. Arya, P. C. Eames, and T. Hyde, “Development of an efficient low-and medium-temperature vacuum flat-plate solar thermal collector,” in Renewable Energy in the Service of Mankind Vol II, Springer International Publishing, 2016, pp. 859–866.
 N. Benz and T. Beikircher, “High efficiency evacuated flat-plate solar collector for process steam production,” Sol. Energy, vol. 65, no. 2, pp. 111–118, 1999.
 P. Henshall, P. Eames, F. Arya, T. Hyde, R. Moss, and S. Shire, “Constant temperature induced stresses in evacuated enclosures for high performance flat plate solar thermal collectors,” Sol. Energy, vol. 127, pp. 250–261, 2016.
 P. C. Eames, “Vacuum glazing: current performance and future prospects,” Vacuum, vol. 82, no. 7, pp. 717–722, 2008.
 J. L. De Segovia, “Physics of outgassing,” Madrid, Spain, 1999.
 S. P. Vendan, L. P. A. Shunmuganathan, T. Manojkumar, and C. S. Thanu, “Study on design of an evacuated tube solar collector for high temperature steam Generation,” Int. J. Emerg. Technol. Adv. Eng., vol. 2, no. 12, pp. 539–541, 2012.
 M. M. Koebel, H. Manz, K. Emanuel Mayerhofer, and B. Keller, “Service-life limitations in vacuum glazing: A transient pressure balance model,” Sol. Energy Mater. Sol. Cells, vol. 94, no. 6, pp. 1015–1024, 2010.
 P. Henshall, R. Moss, F. Arya, P. Eames, S. Shire, and T. Hyde, “An evacuated enclosure design for solar thermal energy applications,” in Grand Renewable Energy International Conference and Exhibition, 2014.
 P. Henshall, E. McKenna, M. Thomson, and P. Eames, “Solar thermal collector component for high-resolution stochastic bottom-up domestic energy demand models,” in Sustainable Energy Technologies Conference, 2015.
 J. Duffie and W. Beckman, Solar engineering of thermal processes, Third. John Wiley and Sons, INC., 2006, pp. 242 - 245.
 J. Wang, P. C. Eames, J. F. Zhao, T. Hyde, and Y. Fang, “Stresses in vacuum glazing fabricated at low temperature,” Sol. Energy Mater. Sol. Cells, vol. 91, no. 4, pp. 290–303, 2007.
 A. Chambers, Basic Vacuum technology, 2nd ed. CRC Press, 1998, pp. 36.
 R. Ramesham, “Evaluation of Non-Evaporable Getters for High Vacuum Hermetic Packages,” 2003.
 P. Gallina, SAES “Personal Communication.” 2015.