Optimum design and orientation of the greenhouses for maximum capture of solar energy in North Tropical Region

• Published in: Energy conversion and management Vol. 105; pp. 1096 - 1104
• Main Authors: El-Maghlany, Wael M., Teamah, Mohamed A., Tanaka, Hiroshi
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-11-2015
• Subjects: Aspect ratio; Cost engineering; Ellipse aspect ratio; Energy conservation; Energy saving; Greenhouses; Mathematical analysis; Optimization; Seasons; Solar energy; Ellipse aspect ratio; Energy saving; Greenhouses; Solar energy
• ISSN: 0196-8904; 1879-2227
• DOI: 10.1016/j.enconman.2015.08.066

•Curved surface of greenhouse plays significant effect on collected solar energy.•Amount of gained energy per unit land area increases with ellipse aspect ratio.•The captured energy during the season per unit land area reaches 4.481GJ/m2.•Optimum orientation changes for different latitude angles.•At Z=4, cost of energy saving per square meter reaches to 50.971$/m2/season.
This investigation is devoted to calculate the amount of solar energy that can be captured by the greenhouse surface. This energy reduces the cost of fossil fuel or any other heating systems used to warm the greenhouse during winter season. The novelty in this study is the handling of the greenhouses surface analytically. The analytical solution is carried out for different elliptic curved surface aspect ratios, to reach the optimum one for maximum captured solar energy. The captured solar energy is calculated from 1st of November to the end of April (cold weather season). The study covers a range of ellipse aspect ratio, Z, from 0.25 to 4.0 and latitude angle ϕ from 24° to 31.2°. Also, the orientation of the greenhouse is studied. Finally, for the optimum case, the amount of energy capture and the energy saving cost are obtained. The results showed that, the captured solar energy per square meter of the greenhouse land area reaches its maximum value at aspect ratio equals 4. The corresponding maximum heating cost savings equals to 50.971$/m2/season.