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Food Chemistry 2018 Journal of Food, Nutrition and Population Health
ISSN: 2577-0586 Page 90
July 23-24, 2018
Rome, Italy
3rd Edition of International Conference on
Agriculture &
Food Chemistry
J Food Nutr Popul Health 2018, Volume 2
DOI: 10.21767/2577-0586-C2-006
Agreenhouse is essentially an enclosed structure, which traps the
short wavelength solar radiation and stores the long wavelength
thermal radiation to create a favourable microclimate for higher
productivity. The sun’s radiation incident on the greenhouse has
two parts: direct radiation and an associated diffuse sky radiation.
The diffuse part is not focused by the lenses and goes right through
Frensel lenses onto the surface of the absorbers. This energy is
absorbed and transformed into heat, which is then transported via the
liquid medium in copper pipes to the water (heat) storage tanks or, if
used, open fish tanks. In this way, an optimal temperature for both
plant cultivation and fish production can be maintained. Stable plant
growth conditions are light, temperature and air humidity. Light for the
photosynthesis of plants comes from the diffuse radiation, which is
without substantial fluctuations and variation throughout most of the
day. The air temperature inside the greenhouse is one of the factors
that have an influence on the precocity of production. The selective
collector acts in a more perceptible way on extreme air temperatures
inside the greenhouse. Hence, the systemmakes it possible to avoid
the excessive deviation of the temperature inside the greenhouse and
provides a favourable microclimate for the precocity of the culture.
Sediment and some associated water from the sediment traps are
used as organic fertiliser for the plant cultivation. The present trend
in greenhouse cultivation is to extend the crop production season
in order to maximise use of the equipment and increase annual
productivity and profitability. However, in many Mediterranean
greenhouses, such practices are limited because the improper
cooling methods (mainly natural or forced ventilation) used do not
provide the desired micro-climatic condition during the summer of a
composite climate. Also, some of these greenhouses have been built
where the meteorological conditions require some heating during the
winter, particularly at night. The worst scenario is during the winter
months when relatively large difference in temperature between day
and night occurs. However, overheating of the greenhouse during the
day is common, even in winter, requiring ventilation of the structure.
Hence, several techniques have been proposed for the storage of the
solar energy received by the greenhouse during the day and its use to
heat the structure at night.
Application of Greenhouses for Sustainable Food Production
Abdeen Mustafa Omer
Energy Research Institute (ERI), United Kingdom