Economy prospects for roof-integrated desalination in greenhouses : -

Abstract

The results presented correspond to climate and market conditions as typical for countries like Tunisia. Three solar energy based system concepts for desalination of irrigation water are described and analysed: 1. Greenhouse-integrated system 2. Single effect process with heat pipe solar collectors 3. Mul-tiple cycle process with flat plate solar collectors. The design of each concept is illustrated and the principal performance is discussed. Water production costs including investment, maintenance and operation costs based on practical experiences are presented and compared. The greenhouse-integrated system is found to be the most economical concept. Compared to concept 3, which has lower water cost than concept 2, the estimated water cost is 60% lower for the greenhouse system (6.8 $/m3).Based on the concepts and water costs, the final revenues for commercial greenhouse growers are evaluated. Included are greenhouse, labour and transport and marketing costs as well as production market values for three typical alternatives of crop cultivation schedules. Here, estimated crop yield reductions for the desalination greenhouse of 15% in relation to a conventional greenhouse are regarded. The most important conclusion is that the desalination greenhouse competes well with the other technologies. Also analysed are future possibilities with more advanced, light selective absorber glass types used in the desalination roof. In this case the yield reduction is 5%. If these glass types are introduced at reasonable costs the greenhouse concept could be well competitive to the other technologies even for a developed solar collector market with 50% cost reduction

Keywords

Greenhouses; Irrigation; Desalination; Economy

Published in

Proceedings
2004, volume: 2004
Publisher: International Solar Energy Society

SLU Editors

• Jilar, Torbjörn

  • Department of Agricultural Biosystems and Technology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Horticulture

Publication identifier

• ISBN: 91-631-4740-8

Permanent link to this page (URI)

https://res.slu.se/id/publ/4439