Study of a pilot photovoltaic-electrolyser-fuel cell power system for a geothermal heat pump heated greenhouse and evaluation of the electrolyser efficiency and operational mode

The intrinsic factor of variability of renewable energy sources often limits their broader use. The photovoltaic solar systems can be provided with a power back up based on a combination of an electrolyser and a fuel cell stack. The integration of solar hydrogen power systems with greenhouse heating equipment can provide a possible option for powering stand-alone greenhouses. The aim of the research under development at the experimental farm of Department of Agro-Environmental Sciences of the University of Bari Aldo Moro is to investigate on the suitable solutions of a power system based on photovoltaic energy and on the use of hydrogen as energy vector, integrated with a ground source heat pump for greenhouse heating in a self sustained way. The excess energy produced by a purpose-built array of solar photovoltaic modules supplies an alkaline electrolyser; the produced hydrogen gas is stored in pressured storage tank. When the solar radiation level is insufficient to meet the heat pump power demand, the fuel cell starts converting the chemical energy stored by the hydrogen fuel into electricity. This paper reports on the description of the realised system. Furthermore the efficiency and the operational mode of the electrolyser were evaluated during a trial period characterised by mutable solar radiant energy. Anyway the electrolyser worked continuously in a transient state producing fluctuations of the hydrogen production and without ever reaching the steady-state conditions. The Faradic efficiency, evaluated by means of an empirical mathematic model, highlights that the suitable working range of the electrolyser was 1.5÷2.5 kW and then for hydrogen production more than 0.21 Nm 3 h –1 .

[1]  E. Cerruto,et al.  Improvement in pesticide application on greenhouse crops: results of a survey about greenhouse structures in Italy , 2008 .

[2]  Giacomo Scarascia Mugnozza Dal fotovoltaico al termico , 2009 .

[3]  John K. Kaldellis,et al.  Optimal design of geothermal–solar greenhouses for the minimisation of fossil fuel consumption , 2006 .

[4]  Brant C. White,et al.  United States patent , 1985 .

[5]  P. Jena Materials for Hydrogen Storage: Past, Present, and Future , 2011 .

[6]  Andreas Züttel,et al.  Materials for hydrogen storage , 2003 .

[7]  Albino Maggio,et al.  Sustainable protected cultivation in a Mediterranean climate. Perspectives and challenges. , 2005 .

[8]  Domenico Casadei,et al.  Impianto sperimentale per la produzione di energia elettrica fotovoltaica con sistema di accumulo ad idrogeno , 2005 .

[9]  R. Valdés,et al.  Procedure for optimal design of hydrogen production plants with reserve storage and a stand-alone photovoltaic power system , 2012 .

[10]  E. David An overview of advanced materials for hydrogen storage , 2005 .

[11]  G. Vox,et al.  Radiometric properties of photoselective and photoluminescent greenhouse plastic films and their effects on peach and cherry tree growth , 2011 .

[12]  Ø. Ulleberg Modeling of advanced alkaline electrolyzers: a system simulation approach , 2003 .

[13]  J. O. Voogt,et al.  Greenhouse production systems for people , 2012 .

[14]  Lynne E. Macaskie,et al.  Integrating dark and light bio-hydrogen production strategies: towards the hydrogen economy , 2009 .

[15]  F. Mueller-Langer,et al.  Techno-economic assessment of hydrogen production processes for the hydrogen economy for the short and medium term , 2007 .

[16]  A. Morán,et al.  Hydrogen production: two stage processes for waste degradation. , 2011, Bioresource technology.

[17]  A. Ganguly,et al.  Modeling and analysis of solar photovoltaic-electrolyzer-fuel cell hybrid power system integrated with a floriculture greenhouse , 2010 .

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

[19]  Jacob Brouwer,et al.  Experimental results for hybrid energy storage systems coupled to photovoltaic generation in residen , 2011 .

[20]  Hüseyin Benli,et al.  A performance comparison between a horizontal source and a vertical source heat pump systems for a greenhouse heating in the mild climate Elaziğ, Turkey , 2013 .

[21]  B. Huyghebaert,et al.  Photovoltaic and geothermal integration system for greenhouse heating: an experimental study. , 2011 .

[22]  Rihab Jallouli,et al.  Sizing, techno-economic and generation management analysis of a stand alone photovoltaic power unit including storage devices , 2012 .

[23]  Onder Ozgener,et al.  Use of solar assisted geothermal heat pump and small wind turbine systems for heating agricultural and residential buildings , 2010 .

[24]  D. D. Feder,et al.  Perspectives and Challenges , 1961 .

[25]  J. Mergel,et al.  Highly efficient advanced alkaline electrolyzer for solar operation , 1992 .

[26]  Guangyi Cao,et al.  Dynamic modeling and sizing optimization of stand-alone photovoltaic power systems using hybrid energy storage technology , 2009 .

[27]  Alberto Pardossi,et al.  Chapter 1: Sustainable Greenhouse Systems. in “Sustainable Agriculture: Technology, Planning and Management”, Augusto Salazar e Ismael Rios Editors, Nova Science Publishers, Inc. NY USA , 2010 .

[28]  Alexandros Sotirios Anifantis,et al.  SOLAR THERMAL COLLECTORS FOR GREENHOUSE HEATING , 2008 .

[29]  J. Ni,et al.  Performance evaluation of ground source heat pump system for greenhouse heating in northern China , 2012 .

[30]  Gerasimos Lyberatos,et al.  Biohydrogen Production from Biomass and Wastes via Dark Fermentation: A Review , 2010 .

[31]  M. J. Khan,et al.  Pre-feasibility study of stand-alone hybrid energy systems for applications in Newfoundland , 2005 .

[32]  F. Kargı,et al.  Bio-hydrogen production from waste materials , 2006 .