Performance of a passive solar heating system in multi-span Moroccan greenhouse

L. Gourdo, H. Fatnassi, K. Achgar, A. Chraibi, B. Ouaddich, A. Wifaya, R. Bouharroud, H. Demrati, A. Bekkaoui, A. Aharoune, L. Bouirden
Greenhouse heating is an absolute necessity in winter season in order to keep air temperature inside the greenhouse above the good crop development conditions. The research of alternative clean energy sources for greenhouse heating has become nowadays more and more actual, due to high heating loads and the rising price of fossil fuels. Among the alternative energies to fossil fuels, the solar energy is the most cost-effective and viable to heat greenhouses in south Mediterranean basin. It is in this context that we have studied the performance of a passive solar heating system placed in multi-span Moroccan greenhouse tomato crop, in order to assess the effect of such system on the microclimate and tomato yield. This passive heating system uses water as heat storage and transfer fluid. The water is stored in black plastic sleeves positioned on both sides of crop rows near the roots. The surplus of solar energy is passively stored in the water during the day and released during the night. Comparison of results between two greenhouses (one equipped with the solar heating system and the other without) show that during the night, this system increased the greenhouse air temperature by a maximum of 3.9°C and reduced the air relative humidity of the greenhouse by 8.5%. This improvement in the microclimate in the heated greenhouse has led to an increase of the yield of fresh tomatoes by 30.7% compared to the control greenhouse.
Gourdo, L., Fatnassi, H., Achgar, K., Chraibi, A., Ouaddich, B., Wifaya, A., Bouharroud, R., Demrati, H., Bekkaoui, A., Aharoune, A. and Bouirden, L. (2020). Performance of a passive solar heating system in multi-span Moroccan greenhouse. Acta Hortic. 1296, 211-218
DOI: 10.17660/ActaHortic.2020.1296.27
solar energy, solar heating system, greenhouse, tomato crop

Acta Horticulturae