International Journal of Energy Engineering          
International Journal of Energy Engineering(IJEE)
Frequency: Quarterly
Editor-in-Chief: Prof. Sri Bandyopadhyay(Australia)
A Variable Insulation System With Potential Application in Cold Climate Greenhouses
Full Paper(PDF, 8967KB)
Greenhouse structures are widely used to enable sheltered plant growth. However, traditional transparent greenhouse structures are generally only used in moderate climates because the cost of the energy required for heating in cold climates is prohibitively high. This paper describes a new approach to the design trade-off between light transmission and thermal insulation in greenhouse structures. Here, a low power variable insulation system combining sunlight-concentrating structures and low cost thermal insulation is shown to be a potentially practical solution. Experimental devices have achieved thermal insulation values exceeding 3.33 m2K/W (compared to 0.42 m2K/W for triple layer polycarbonate greenhouses) while also maintaining light transmittance values greater than 70%.
Keywords:Variable Thermal Insulation; Compound Parabolic Concentrator; Light Valve; Cold Climate Greenhouses
Author: Angel Valerio1, Michele Mossman1, Deborah Henderson2, Lorne Whitehead1
1.Department of Physics and Astronomy, The University of British Columbia, 6224 Agricultural Road, Vancouver, Canada
2.Institute for Sustainable Horticulture, Kwantlen Polytechnic University, 12666 72nd Avenue - Surrey, Canada
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