Evaluation of Compressor Heat Pump for Root Zone Heating as an Alternative Heating Source for Leafy Vegetable Cultivation

Abstract

Protected horticulture is a high energy-consuming sector in which the optimization of energy use and cost for heating facilities is strategic in achieving high environmental and economic sustainability of production. The main aim of the project was to evaluate the use of a heat pump for basal heating as an alternative technology to grow crops with reduced canopies, such as basil. During the test, an area of the greenhouse contained two systems of coaxial pipes circulating warm water from a heat pump and a condensing boiler. These pipes were placed above the growing media. At the same time, a separate area of the same greenhouse contained a traditional heating system consisting of an air heater, the solution commonly used to heat greenhouses. Microclimatic conditions and energy consumption were analyzed for the three heating technologies. The energy analysis of the three experimental heating options showed that all of them could ensure suitable thermal conditions for cultivation in the winter period. Overall, the results confirmed the energy saving resulting from the adoption of the heat pump, underlining the importance of this device in terms of the support that the energy-saving goal receives.

Energy Use Efficiency and Carbon Footprint of Greenhouse Hydroponic Cultivation Using Public Grid and PVs as Energy Providers

“…The lowest EUE both in PPG and PV tanks were observed during the summer as a result of the higher cooling needs and the insufficient energy consumption of the photovoltaic panels, in combination with lower yield. Compared to [11], where different heating systems methods were used, the energy consumption in the current experimental study was lower. More specifically, during the similar experimental season, from February to March, the energy consumption per square meter and on an average per day amounted to 1 kWh m −2 d −1 for the the PPG tank and 0.73 kWh m −2 d −1 for the PV.…”

“…In the second scenario, a heat pump was used, while in the third scenario, a condenser boiler was selected and the pipes were placed on the surface of the crop. Regarding the total energy consumption from February to March, during 49 days of cultivation, the highest value was observed in the third scenario and was calculated to be 300.25 kWh m −2 , followed by the first scenario, with 175.91 kWh m −2 , while the second scenario had the lowest value of 159.41 kWh m −2 [11].…”

“…In the Mediterranean basin, the energy consumption for the cooling of the greenhouses was estimated at 100 kWh m −2 [10]. Three different greenhouse-heating scenarios were evaluated in Italy [11]. In the first scenario, the greenhouse was heated by using an air heater.…”

WP3 – Innovation in Agriculture and Forestry Sector for Energetic Sustainability

“…Papers submitted and published in this Special Issue "WP3-Innovation in Agriculture and Forestry Sector for Energetic Sustainability" bring together some of the latest research results in the field of biomass valorization and the process of energy production and climate change and other items about energetic sustainability [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Moreover it is very important to evaluate the safety aspects for energy plant use [21][22][23][24].…”

WP3—Innovation in Agriculture and Forestry Sector for Energetic Sustainability

“…Papers submitted and published in this Special Issue "WP3-Innovation in Agriculture and Forestry Sector for Energetic Sustainability" bring together some of the latest research results in the field of biomass valorization and the process of energy production and climate change and other items about energetic sustainability [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Moreover it is very important to evaluate the safety aspects for energy plant use [21][22][23][24].…”