Review Design and technology for greenhouse cooling in tropical and subtropical regions: A review K.S. Kumar *, K.N. Tiwari, Madan K. Jha Indian Institute of Technology, Kharagpur 721302, India Contents 1. Introduction .................................................................................................... 1270 2. Greenhouse design and functional characteristics ...................................................................... 1270 2.1. Design ................................................................................................... 1270 2.2. Orientation and shape ...................................................................................... 1270 2.3. Height ................................................................................................... 1271 2.4. Covering materials ......................................................................................... 1271 2.5. Ventilation area............................................................................................ 1271 2.6. Insect-proof nets ........................................................................................... 1271 3. Greenhouse cooling technologies ................................................................................... 1271 3.1. Natural ventilation ......................................................................................... 1272 3.2. Evaporative cooling......................................................................................... 1272 3.2.1. Fan-pad system .................................................................................... 1272 3.2.2. Fog/mist system.................................................................................... 1273 3.2.3. Roof evaporative cooling ............................................................................. 1273 4. Shading........................................................................................................ 1273 5. Composite system ............................................................................................... 1273 5.1. Earth-to-air heat exchange system ............................................................................ 1273 6. Greenhouse design and cooling approach in tropical and subtropical regions ................................................ 1274 7. Conclusions and recommendations.................................................................................. 1274 8. Research gaps for future research ................................................................................... 1274 References ..................................................................................................... 1274 Energy and Buildings 41 (2009) 1269–1275 ARTICLE INFO Article history: Received 26 July 2009 Accepted 10 August 2009 Keywords: Greenhouse Structural design Natural ventilation Evaporative cooling Near infrared radiation Far infrared radiation Insect-proof nets Earth-to-air heat exchange system ABSTRACT Greenhouse technology is a viable option for sustainable crop production in the regions of adverse climatic conditions. High summer temperature is a major setback for successful greenhouse crop production throughout year. The main intent of the paper is to present a comprehensive review on the design and technology for cooling of greenhouse during summer months. Effect of characteristic design parameters on greenhouse microclimate and the applicable cooling technologies have been discussed. A detailed survey of literature revealed that, apart from cooling, studies on greenhouse design, evaluation of new cladding materials for greenhouse covering and natural ventilation with respect to local climate and agronomic condition is necessary to achieve desirable benefits. Analysis of the earlier studies revealed that a naturally ventilated greenhouse with larger ventilation areas (15–30%), provided at the ridge and sides covered with insect-proof nets of 20–40 mesh size with covering material properties of NIR (near infrared radiation) reflection during the day and FIR (far infrared radiation) reflection during night is suitable for greenhouse production throughout year in tropical and subtropical regions. Based on the review, salient areas in need of further research are focused. ß 2009 Elsevier B.V. All rights reserved. * Corresponding author at: Agricultural and Food Engineering Department, Indian Institute of Technology, Kharagpur 721302, India. Tel.: +91 3222 283151/91 9735370213 (M); fax: +91 3222 282243. E-mail address: kaduluru@yahoo.co.in (K.S. Kumar). Contents lists available at ScienceDirect Energy and Buildings journal homepage: www.elsevier.com/locate/enbuild 0378-7788/$ – see front matter ß 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.enbuild.2009.08.003