Energy demand hourly simulations and energy saving strategies in greenhouses for the Mediterranean climate

This research has been devoted to the selection of the most favourable plant solutions for ventilation, heating and cooling, thermo-hygrometric control of a greenhouse, in the framework of the energy saving and the environmental protection. The identified plant solutions include shading of glazing surfaces, natural ventilation by means of controlled opening windows, forced convection of external air and forced convection of air treated by the HVAC system for both heating and cooling. The selected solution combines HVAC system to a Ground Coupled Heat Pump (GCHP), which is an innovative renewable technology applied to greenhouse buildings. The energy demand and thermal loads of the greenhouse to fulfil the requested internal design conditions have been evaluated through an hourly numerical simulation, using the Energy Plus (E-plus) software. The overall heat balance of the greenhouse also includes the latent heat exchange due to crop evapotranspiration, accounted through an original iterative calculation procedure that combines the E-plus dynamic simulations and the FAO Penman-Monteith method. The obtained hourly thermal loads have been used to size the borehole field for the geothermal heat pump by using a dedicated GCHP hourly simulation tool.

[1]  Onder Ozgener,et al.  A parametrical study on the energetic and exergetic assessment of a solar-assisted vertical ground-source heat pump system used for heating a greenhouse , 2007 .

[2]  V. Sethi.  On the selection of shape and orientation of a greenhouse: Thermal modeling and experimental validation , 2009 .

[3]  V. P. Sethi,et al.  Survey and evaluation of heating technologies for worldwide agricultural greenhouse applications , 2008 .

[4]  K. A. Jamal.  Greenhouse cooling in hot countries , 1994 .

[5]  K. Al-Jamal.  Greenhouse cooling in hot countries , 1994 .

[6]  A. Sari,et al.  Lauric and palmitic acids eutectic mixture as latent heat storage material for low temperature heating applications , 2005 .

[7]  Ibrahim M. Al-Helal,et al.  Solar energy utilization by a greenhouse: General relations , 2011 .

[8]  Pitam Chandra,et al.  Effect of greenhouse design parameters on conservation of energy for greenhouse environmental control , 2002 .

[9]  G. C. Bakos,et al.  Greenhouse heating using geothermal energy , 1999 .

[10]  Enrico Fabrizio,et al.  Energy reduction measures in agricultural greenhouses heating: Envelope, systems and solar energy collection , 2012 .

[11]  Amílcar Fasulo,et al.  Geothermal contribution to greenhouse heating , 1999 .

[12]  V. Sethi,et al.  Survey of cooling technologies for worldwide agricultural greenhouse applications , 2007 .

[13]  Richard Labib,et al.  A Multiple Load Aggregation Algorithm for Annual Hourly Simulations of GCHP Systems , 2004 .

[14]  G. Mihalakakou,et al.  Energy conservation in greenhouses with buried pipes , 1996 .