Geothermal heat pumps for sustainable farm climatization and field irrigation

Abstract In intensive breeding farms, maintaining an adequate indoor thermal environment and air quality is crucial in order to establish healthy conditions and increase productivity. In the EU, fossil fuels and electricity are the main energy sources adopted for this purpose, yet introducing renewable energy sources and efficient Heating Ventilating Air Conditioning systems would reduce energy consumption and improve sustainability. Another environmental concern in agricultural production is related to the intensive use of fertilizers, causing nitrate contamination in surface water and groundwater. Therefore, innovative strategies to reduce fertilizers and simultaneously reduce primary energy consumption are worthy of investigation. This paper addresses both issues, studying the application of geothermal heat pumps in the agro-zootechnical sector, where they are rarely applied and thus their potential needs to be verified. The study considers systems based on the closed loop configuration, i.e. Ground Source Heat Pumps (GSHP), and on the open loop configuration, i.e. Groundwater Heat Pumps (GWHP). Firstly, a pilot GSHP system for a piglet stable in Northern Italy is presented. Thanks to the use of both ground source and thermal recovery of air ventilation, the system achieves an appreciable reduction in both primary energy consumption and running costs, compared with a more traditional system typically adopted in this kind of farm. Secondly, the feasibility of an innovative concept of a GWHP combined with the irrigation system is studied through numerical modelling. The area of the piglet stable is represented in a flow and heat transport model; groundwater used by the heat pump is re-injected up-gradient during the cold season, while it is used for irrigation during the warm season. The system would provide energy-efficient climatization to the farm stables and, at the same time, promote the reuse of nitrogen in cultivated fields as a result of groundwater recirculation through irrigation.

[1]  Adriana Angelotti,et al.  A Numerical Study on the Impact of Grouting Material on Borehole Heat Exchangers Performance in Aquifers , 2017 .

[2]  S. Yun,et al.  Determination of natural backgrounds and thresholds of nitrate in South Korean groundwater using model-based statistical approaches , 2015 .

[3]  J. Lund,et al.  Direct utilization of geothermal energy 2015 worldwide review , 2011 .

[4]  Stephen P. Kavanaugh,et al.  Ground Source Heat Pumps : Design of Geothermal Systems for Commercial and Institutional Buildings , 1997 .

[5]  R. Aravena,et al.  Interaction between shallow and deep aquifers in the Tivoli Plain (Central Italy) enhanced by groundwater extraction: A multi-isotope approach and geochemical modeling , 2012 .

[6]  A. Pouyan Nejadhashemi,et al.  Climate change and livestock: Impacts, adaptation, and mitigation , 2017 .

[7]  Christian D. Langevin,et al.  Addition of simultaneous heat and solute transport and variable fluid viscosity to SEAWAT , 2006, Comput. Geosci..

[8]  Alessandro Casasso,et al.  Modelling thermal recycling occurring in groundwater heat pumps (GWHPs) , 2015 .

[9]  A. Agazzi,et al.  Alternative antimicrobials in the nutrition of postweaning piglets , 2002, Veterinary Record.

[10]  B. Clothier,et al.  Estimation of nitrate retention in a Ferralsol by a transient‐flow method , 2003 .

[11]  Son V. Nghiem,et al.  Groundwater vulnerability maps derived from a time-dependent method using satellite scatterometer data , 2015, Hydrogeology Journal.

[12]  SOLUZIONI ANALITICHE PER LA DETERMINAZIONE DELLO SPARTIACQUE PIEZOMETRICO DELLA ZONA DI CATTURA DI UNA BARRIERA DI POZZI , 2012 .

[13]  Beijia Huang,et al.  Life cycle sustainability assessment of ground source heat pump in Shanghai, China , 2016 .

[14]  Riccardo Bersezio,et al.  Combining sedimentological and geophysical data for high-resolution 3-D mapping of fluvial architectural elements in the Quaternary Po plain (Italy) , 2007 .

[15]  Hossein Yousefi,et al.  Numerical modeling and economic analysis of a ground source heat pump for supplying energy for a greenhouse in Alborz province, Iran , 2016 .

[16]  C. Welty,et al.  A Critical Review of Data on Field-Scale Dispersion in Aquifers , 1992 .

[17]  Md. Manirul Islam,et al.  Evaluation of a ground source geothermal heat pump to save energy and reduce CO2 and noxious gas emissions in a pig house , 2016 .

[18]  Nurettin Yamankaradeniz,et al.  Experimental study of horizontal ground source heat pump performance for mild climate in Turkey , 2009 .

[19]  S. Russo,et al.  Low-enthalpy geothermal energy: An opportunity to meet increasing energy needs and reduce CO2 and atmospheric pollutant emissions in Piemonte, Italy , 2009 .

[20]  Peter J. Thorburn,et al.  Nitrate in groundwaters of intensive agricultural areas in coastal Northeastern Australia , 2003 .

[21]  Antonio Colmenar-Santos,et al.  Geothermal source heat pumps under energy services companies finance scheme to increase energy efficiency and production in stockbreeding facilities , 2015 .

[22]  M. Giudici,et al.  Hydrogeophysical imaging of alluvial aquifers: electrostratigraphic units in the quaternary Po alluvial plain (Italy) , 2012, International Journal of Earth Sciences.

[23]  Cristiano Ballabio,et al.  Aquifer nitrate vulnerability assessment using positive and negative weights of evidence methods, Milan, Italy , 2012, Comput. Geosci..

[24]  J. Desmedt,et al.  Improving the energy efficiency of ground-source heat pump systems in heating dominated school buildings: A case study in Belgium , 2017 .

[25]  M. Z. Wang,et al.  Economic Performance Study on the Application of Ground Source Heat Pump System in Swine Farms in Beijing China , 2012 .

[26]  Arlen W. Harbaugh,et al.  MODFLOW-2000, The U.S. Geological Survey Modular Ground-Water Model - User Guide to Modularization Concepts and the Ground-Water Flow Process , 2000 .

[27]  Sungho Park,et al.  Geothermal resource assessment in Korea , 2010 .

[28]  C. Watson,et al.  Spatial and temporal variations in groundwater nitrate at an intensive dairy farm in south-east Ireland: insights from stable isotope data , 2011 .

[29]  Hikari Fujii,et al.  Cooling tests, numerical modeling and economic analysis of semi-open loop ground source heat pump system , 2018 .

[30]  J. F. Devlin,et al.  Challenges and a Strategy for Agricultural BMP Monitoring and Remediation of Nitrate Contamination in Unconsolidated Aquifers , 2015 .

[31]  Wei Zhang,et al.  Nitrate pollution of groundwater in northern China , 1996 .

[32]  Improving the environment for weaned piglets using polypropylene fabrics above the animals in cold periods , 2015, International Journal of Biometeorology.

[33]  D. Masseroni,et al.  Prospects for Improving Gravity-Fed Surface Irrigation Systems in Mediterranean European Contexts , 2017 .

[34]  R. Aravena,et al.  Evaluation of the sources of nitrogen compounds and their influence on the biological communities in the hyporheic zone of the Sagittario River, Italy: an isotopic and biological approach , 2017 .

[35]  Weibo Yang,et al.  A two-region simulation model of vertical U-tube ground heat exchanger and its experimental verification , 2009 .

[36]  Adriana Angelotti,et al.  Energy performance and thermal impact of a Borehole Heat Exchanger in a sandy aquifer: Influence of the groundwater velocity , 2014 .

[37]  Enrico Fabrizio,et al.  Energy Performance and Indoor Environmental Control of Animal Houses: A Modelling Tool☆ , 2015 .

[38]  Patrick Durand,et al.  Groundwater resource vulnerability and spatial variability of nitrate contamination: Insights from high density tubewell monitoring in a hard rock aquifer. , 2017, The Science of the total environment.

[39]  Arif Hepbasli,et al.  Exergoeconomic evaluation of a ground-source heat pump food dryer at varying dead state temperatures , 2017 .

[40]  Paul P. Wang,et al.  MT3DMS: A Modular Three-Dimensional Multispecies Transport Model for Simulation of Advection, Dispersion, and Chemical Reactions of Contaminants in Groundwater Systems; Documentation and User's Guide , 1999 .

[41]  Pan Xu,et al.  Feasibility of ground coupled heat pumps in office buildings: A China study , 2016 .