Comparing energy flow of greenhouse and open-field cucumber production systems in Iran

Abstract

The aim of this study was to compare the energy flow in greenhouse and open-field cucumber production systems in Iran. For this purpose, data were collected by using a face-to-face questionnaire performed with 100 cucumber farmers (50 farmers for greenhouse systems and 50 farmers for open-field cucumber systems) in summer 2010. Farmers were selected by random sampling method in Tehran and Kermanshah province of Iran. The results revealed that total energy consumption amount in greenhouse systems was 11709452.43 MJha-1 while in open-field systems it was 78476.33 MJha-1. The highest share of total input energy in greenhouse cucumber systems was recorded for diesel fuel with 99% while the highest share of input energy in open-field cucumber systems was observed for electricity power with 38%. Energy use efficiency in greenhouse systems (0.017) was lower than open-field systems (0.33). Energy productivity and specific energy in greenhouse production systems were 0.02 KgMJ-1 and 46.84 MJKg-1, respectively while that in open-field production systems were 0.41 KgMJ-1 and 2.38 MJKg-1, respectively. Accordingly, net energy in open-field cucumber production systems (-52171.93 MJha-1) was higher than greenhouse cucumber production systems (-11509452.43 MJha-1). Key words: Greenhouse, open-field, energy use efficiency.