Performance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generation

The study presents a complete one-dimensional model to evaluate the parameters that describe the operation of a Proton Exchange Membrane (PEM) electrolyzer and PEM fuel cell. The mathematical modeling is implemented in Matlab/Simulink® software to evaluate the influence of parameters such as tempera...

Full description

Autores:
Escobar Yonoff, Rony
Maestre Cambronel, Daniel Esteban
Charry, Sebastián
Rincón Montenegro, Adriana
Portnoy, Ivan
Tipo de recurso:
Article of journal
Fecha de publicación:
2021
Institución:
Corporación Universidad de la Costa
Repositorio:
REDICUC - Repositorio CUC
Idioma:
eng
OAI Identifier:
oai:repositorio.cuc.edu.co:11323/8362
Acceso en línea:
https://hdl.handle.net/11323/8362
https://doi.org/10.1016/j.heliyon.2021.e06506
https://repositorio.cuc.edu.co/
Palabra clave:
Electrolyzer
Fuel cell
Economic assessment
Proton exchange membrane
Electric power generation
Rights
openAccess
License
CC0 1.0 Universal
id RCUC2_74d2746903512fe276baf9972427ab8a
oai_identifier_str oai:repositorio.cuc.edu.co:11323/8362
network_acronym_str RCUC2
network_name_str REDICUC - Repositorio CUC
repository_id_str
dc.title.eng.fl_str_mv Performance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generation
title Performance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generation
spellingShingle Performance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generation
Electrolyzer
Fuel cell
Economic assessment
Proton exchange membrane
Electric power generation
title_short Performance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generation
title_full Performance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generation
title_fullStr Performance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generation
title_full_unstemmed Performance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generation
title_sort Performance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generation
dc.creator.fl_str_mv Escobar Yonoff, Rony
Maestre Cambronel, Daniel Esteban
Charry, Sebastián
Rincón Montenegro, Adriana
Portnoy, Ivan
dc.contributor.author.spa.fl_str_mv Escobar Yonoff, Rony
Maestre Cambronel, Daniel Esteban
Charry, Sebastián
Rincón Montenegro, Adriana
Portnoy, Ivan
dc.subject.eng.fl_str_mv Electrolyzer
Fuel cell
Economic assessment
Proton exchange membrane
Electric power generation
topic Electrolyzer
Fuel cell
Economic assessment
Proton exchange membrane
Electric power generation
description The study presents a complete one-dimensional model to evaluate the parameters that describe the operation of a Proton Exchange Membrane (PEM) electrolyzer and PEM fuel cell. The mathematical modeling is implemented in Matlab/Simulink® software to evaluate the influence of parameters such as temperature, pressure, and overpotentials on the overall performance. The models are further merged into an integrated electrolyzer-fuel cell system for electrical power generation. The operational description of the integrated system focuses on estimating the overall efficiency as a novel indicator. Additionally, the study presents an economic assessment to evaluate the cost-effectiveness based on different economic metrics such as capital cost, electricity cost, and payback period. The parametric analysis showed that as the temperature rises from 30 to 70 °C in both devices, the efficiency is improved between 5-20%. In contrast, pressure differences feature less relevance on the overall performance. Ohmic and activation overpotentials are highlighted for the highest impact on the generated and required voltage. Overall, the current density exhibited an inverse relation with the efficiency of both devices. The economic evaluation revealed that the integrated system can operate at variable load conditions while maintaining an electricity cost between 0.3-0.45 $/kWh. Also, the capital cost can be reduced up to 25% while operating at a low current density and maximum temperature. The payback period varies between 6-10 years for an operational temperature of 70 °C, which reinforces the viability of the system. Overall, hydrogen-powered systems stand as a promising technology to overcome energy transition as they provide robust operation from both energetic and economic viewpoints.
publishDate 2021
dc.date.accessioned.none.fl_str_mv 2021-06-09T16:07:48Z
dc.date.available.none.fl_str_mv 2021-06-09T16:07:48Z
dc.date.issued.none.fl_str_mv 2021
dc.type.spa.fl_str_mv Artículo de revista
dc.type.coar.fl_str_mv http://purl.org/coar/resource_type/c_2df8fbb1
dc.type.coar.spa.fl_str_mv http://purl.org/coar/resource_type/c_6501
dc.type.content.spa.fl_str_mv Text
dc.type.driver.spa.fl_str_mv info:eu-repo/semantics/article
dc.type.redcol.spa.fl_str_mv http://purl.org/redcol/resource_type/ART
dc.type.version.spa.fl_str_mv info:eu-repo/semantics/acceptedVersion
format http://purl.org/coar/resource_type/c_6501
status_str acceptedVersion
dc.identifier.issn.spa.fl_str_mv 2405-8440
dc.identifier.uri.spa.fl_str_mv https://hdl.handle.net/11323/8362
dc.identifier.doi.spa.fl_str_mv https://doi.org/10.1016/j.heliyon.2021.e06506
dc.identifier.instname.spa.fl_str_mv Corporación Universidad de la Costa
dc.identifier.reponame.spa.fl_str_mv REDICUC - Repositorio CUC
dc.identifier.repourl.spa.fl_str_mv https://repositorio.cuc.edu.co/
identifier_str_mv 2405-8440
Corporación Universidad de la Costa
REDICUC - Repositorio CUC
url https://hdl.handle.net/11323/8362
https://doi.org/10.1016/j.heliyon.2021.e06506
https://repositorio.cuc.edu.co/
dc.language.iso.none.fl_str_mv eng
language eng
dc.relation.references.spa.fl_str_mv [1] G. Abu-Rumman, A.I. Khdair, S.I. Khdair, Current status and future investment potential in renewable energy in Jordan: an overview, Heliyon 6 (2) (2020), e03346.
[2] G.V. Ochoa, C. Isaza-Roldan, J. Duarte Forero, Economic and exergo-advance analysis of a waste heat recovery system based on regenerative organic rankine cycle under organic fluids with low global warming potential, Energies 13 (6) (2020) 1317.
[3] A. Ursúa, P. Sanchis, Static–dynamic modelling of the electrical behaviour of a commercial advanced alkaline water electrolyser, Int. J. Hydrogen Energy 37 (24) (2012) 18598–18614.
[4] K. Zeng, D. Zhang, Recent progress in alkaline water electrolysis for hydrogen production and applications, Prog. Energy Combust. Sci. 36 (3) (2010) 307–326.
[5] G. Amador, et al., Characteristics of auto-ignition in internal combustion engines operated with gaseous fuels of variable methane number, J. Energy Resour. Technol. 139 (2017).
[6] J. Duarte Forero, G. Valencia Ochoa, J. Piero Rojas, Effect of the geometric profile of top ring on the tribological characteristics of a low-displacement diesel engine, Lubricants 8 (8) (2020) 83.
[7] G. Valencia, C. Penaloza, J. Forero, Thermo-economic assessment of a gas ~ microturbine-absorption chiller trigeneration system under different compressor inlet air temperatures, Energies 12 (2019) 4643.
[8] F. Guti errez-Martín, L. Amodio, M. Pagano, Hydrogen production by water electrolysis and off-grid solar PV, Int. J. Hydrogen Energy xxxx (2020).
[9] M.H.S. Bargal, M.A.A. Abdelkareem, Q. Tao, J. Li, J. Shi, Y. Wang, Liquid cooling techniques in proton exchange membrane fuel cell stacks: a detailed survey, Alexandria Eng. J. 59 (2) (2020) 635–655.
[10] R.E. Yonoff, G.V. Ochoa, Y. Cardenas-Escorcia, J.I. Silva-Ortega, L. Merino-Stand, ~ Research trends in proton exchange membrane fuel cells during 2008–2018: a bibliometric analysis, Heliyon 5 (5) (2019), e01724.
[11] M. Abdollahzadeh, P. Ribeirinha, M. Boaventura, A. Mendes, Three-dimensional modeling of PEMFC with contaminated anode fuel, Energy 152 (2018) 939–959.
[12] M. Sahraoui, Y. Bichiou, K. Halouani, Three-dimensional modeling of water transport in PEMFC, Int. J. Hydrogen Energy 38 (2012).
[13] J.-P. Kone, X. Zhang, Y. Yan, G. Hu, G. Ahmadi, Three-dimensional multiphase flow computational fluid dynamics models for proton exchange membrane fuel cell: a theoretical development, J. Comput. Multiph. Flows 9 (2017), 1757482X1769234.
[14] K. Shekhar, An Investigation into the Minimum Dimensionality Required for Accurate Simulation of Proton Exchange Membrane Fuel Cells by the Comparison between 1- and 3-dimension Models, 2013.
[15] Z. Abdin, C.J. Webb, E.M. Gray, PEM fuel cell model and simulation in Matlab–Simulink based on physical parameters, Energy 116 (2016) 1131–1144.
[16] S.L. Chavan, D.B. Talange, Modeling and performance evaluation of PEM fuel cell by controlling its input parameters, Energy 138 (2017) 437–445.
[17] T. Yigit, O.F. Selamet, Mathematical modeling and dynamic Simulink simulation of high-pressure PEM electrolyzer system, Int. J. Hydrogen Energy 41 (32) (2016) 13901–13914.
[18] Z. Abdin, C.J. Webb, E.M. Gray, Modelling and simulation of an alkaline electrolyser cell, Energy 138 (2017) 316–331.
[19] B. Han, S.M. Steen, J. Mo, F.-Y. Zhang, Electrochemical performance modeling of a proton exchange membrane electrolyzer cell for hydrogen energy, Int. J. Hydrogen Energy 40 (22) (2015) 7006–7016.
[20] M. Alibaba, R. Pourdarbani, M.H.K. Manesh, G.V. Ochoa, J.D. Forero, Thermodynamic, exergo-economic and exergo-environmental analysis of hybrid geothermal-solar power plant based on ORC cycle using emergy concept, Heliyon 6 (4) (2020), e03758.
[21] K. Moorthy, N. Patwa, Y. Gupta, et al., Breaking barriers in deployment of renewable energy, Heliyon 5 (1) (2019), e01166.
[22] F. Alshehri, V.G. Su arez, J.L. Rueda Torres, A. Perilla, M.A.M.M. van der Meijden, Modelling and evaluation of PEM hydrogen technologies for frequency ancillary services in future multi-energy sustainable power systems, Heliyon 5 (4) (2019), e01396.
[23] C.A. Frangopoulos, L.G. Nakos, Development of a model for thermoeconomic design and operation optimization of a PEM fuel cell system, Energy 31 (10–11) (2006) 1501–1519.
[24] A.A. AlZahrani, I. Dincer, Exergoeconomic analysis of hydrogen production using a standalone high-temperature electrolyzer, Int. J. Hydrogen Energy xxxx (2020).
[25] T. Taner, S.A.H. Naqvi, M. Ozkaymak, Techno-economic analysis of a more efficient hydrogen generation system prototype: a case study of PEM electrolyzer with Cr-C coated SS304 bipolar plates, Fuel Cells 19 (1) (2019) 19–26.
[26] E.I. Zoulias, N. Lymberopoulos, Techno-economic analysis of the integration of hydrogen energy technologies in renewable energy-based stand-alone power systems, Renew. Energy 32 (4) (2007) 680–696.
[27] M. Thema, F. Bauer, M. Sterner, Power-to-Gas: electrolysis and methanation status review, Renew. Sustain. Energy Rev. 112 (Sep-2019) 775–787. Elsevier Ltd.
[28] H. Steeb, W. Seeger, H. Aba Oud, Hysolar: an overview on the German-Saudi Arabian programme on solar hydrogen, Int. J. Hydrogen Energy 19 (8) (1994) 683–686.
[29] T. Lepage, M. Kammoun, Q. Schmetz, A. Richel, Biomass-to-hydrogen: a review of main routes production, processes evaluation and techno-economical assessment, Biomass Bioenergy 144 (Jan-2021) 105920. Elsevier Ltd.
[30] D. Milani, A. Kiani, R. McNaughton, Renewable-powered hydrogen economy from Australia’s perspective, Int. J. Hydrogen Energy 45 (46) (2020) 24125–24145.
[31] I. Dincer, C. Acar, Review and evaluation of hydrogen production methods for better sustainability, Int. J. Hydrogen Energy 40 (34) (2014) 11094–11111.
[32] K.K.T. Thanapalan, J.G. Williams, G.P. Liu, D. Rees, Modelling OF a PEM fuel cell system, IFAC Proc. Vol. 41 (2) (2008) 4636–4641.
[33] T. Mennola, et al., Mass transport in the cathode of a free-breathing polymer electrolyte membrane fuel cell, J. Appl. Electrochem. 33 (11) (2003) 979–987.
[34] H. Pukrushpan, T. Jay, Anna G. Stefanopoulou, Peng, Control of Fuel Cell Power Systems, Springer, 2004.
[35] J.H. Nam, M. Kaviany, Effective diffusivity and water-saturation distribution in single- and two-layer PEMFC diffusion medium, Int. J. Heat Mass Tran. 46 (24) (2003) 4595–4611.
[36] R. García-Valverde, N. Espinosa, A. Urbina, Simple PEM water electrolyser model and experimental validation, Int. J. Hydrogen Energy 37 (2) (2012) 1927–1938.
[37] H. Gorgün, Dynamic modelling of a proton exchange membrane (PEM) electrolyzer, € Int. J. Hydrogen Energy 31 (1) (2006) 29–38.
[38] K.S. V Santhanam, R.J. Press, M.J. Miri, A. V Bailey, G.A. Takacs, Introduction to Hydrogen Technology, Wiley, 2017.
[39] C. Vallieres, D. Winkelmann, D. Roizard, E. Favre, P. Scharfer, M. Kind, On Schroeder’s paradox, J. Membr. Sci. 278 (1) (2006) 357–364.
[40] L. Onishi, J. Prausnitz, WaterNafion equilibria. Absence of Schroeder’s paradox, J. Phys. Chem. B 111 (2007) 10166–10173.
[41] T.A. Zawodzinski, M. Neeman, L.O. Sillerud, S. Gottesfeld, Determination of water diffusion coefficients in perfluorosulfonate ionomeric membranes, J. Phys. Chem. 95 (15) (1991) 6040–6044.
[42] F. Marangio, M. Santarelli, M. Calì, Theoretical model and experimental analysis of a high pressure PEM water electrolyser for hydrogen production, Int. J. Hydrogen Energy 34 (3) (2009) 1143–1158.
[43] D.J. Kim, M.J. Jo, S.Y. Nam, A review of polymer–nanocomposite electrolyte membranes for fuel cell application, J. Ind. Eng. Chem. 21 (2015) 36–52.
[44] J. Qi, Y. Zhai, J. St-Pierre, Effect of contaminant mixtures in air on proton exchange membrane fuel cell performance, J. Power Sources 413 (2019) 86–97.
[45] J. Milewski, G. Guandalini, S. Campanari, Modeling an alkaline electrolysis cell through reduced-order and loss-estimate approaches, J. Power Sources 269 (2014) 203–211.
[46] P.D. Beattie, V.I. Basura, S. Holdcroft, Temperature and pressure dependence of O2 reduction at Pt∣Nafion® 117 and Pt∣BAM® 407 interfaces, J. Electroanal. Chem. 468 (2) (1999) 180–192.
[47] N.M. Markovi c, B.N. Grgur, P.N. Ross, Temperature-dependent hydrogen electrochemistry on platinum low-index single-crystal surfaces in acid solutions, J. Phys. Chem. B 101 (27) (1997) 5405–5413.
[48] M.G. Santarelli, M.F. Torchio, P. Cochis, Parameters estimation of a PEM fuel cell polarization curve and analysis of their behavior with temperature, J. Power Sources 159 (2) (2006) 824–835.
[49] T.E. Springer, T.A. Zawodzinski, S. Gottesfeld, Polymer electrolyte fuel cell model, J. Electrochem. Soc. 138 (8) (1991) 2334–2342.
[50] F. Barbir, Fuel cell electrochemistry, in: PEM Fuel Cells: Theory and Practice, Academic Press, Burlington, 2005, pp. 33–72.
[51] R.M. Dell, P.T. Moseley, D.A.J. Rand, Hydrogen, fuel cells and fuel cell vehicles, in: Towards sustainable road transport, Academic Press, Boston, 2014, pp. 260–295.
[52] F. Barbir, T. Gomez, Ef ficiency and economics of proton exchange membrane (PEM) fuel cells, Int. J. Hydrogen Energy 22 (10–11) (1997) 1027–1037.
[53] F. Barbir, Fuel cell applications, in: F. Barbir (Ed.), PEM Fuel Cells, second ed., Academic Press, Boston, 2013, pp. 373–434.
[54] L. Zhou, Progress and problems in hydrogen storage methods, Renew. Sustain. Energy Rev. 9 (4) (Aug-2005) 395–408. Elsevier Ltd.
[55] S.K. Kamarudin, W.R.W. Daud, A. Md. Som, M.S. Takriff, A.W. Mohammad, Technical design and economic evaluation of a PEM fuel cell system, J. Power Sources 157 (2) (2006) 641–649.
[56] S. Rahimi, M. Meratizaman, S. Monadizadeh, M. Amidpour, Techno-economic analysis of wind turbine-PEM (polymer electrolyte membrane) fuel cell hybrid system in standalone area, Energy 67 (2014) 381–396.
[57] A. Mayyas, et al., Manufacturing cost analysis for proton exchange membrane water electrolyzers manufacturing cost analysis for proton exchange membrane water electrolyzers, Natl. Renew. Energy Lab. (2019) 65. August.
[58] R. Yukesh Kannah, et al., Techno-economic assessment of various hydrogen production methods – A review, Bioresour. Technol. 319 (Jan-2021) 124175. Elsevier Ltd.
[59] G. Valencia Ochoa, C. Acevedo Penaloza, J. Duarte Forero, Thermoeconomic ~ optimization with PSO algorithm of waste heat recovery systems based on organic rankine cycle system for a natural gas engine, Energies 12 (21) (2019) 4165.
[60] F. Consuegra, A. Bula, W. Guillín, J. S anchez, J. Duarte Forero, Instantaneous incylinder volume considering deformation and clearance due to lubricating film in reciprocating internal combustion engines, Energies 12 (8) (2019) 1437.
[61] G. Valencia Ochoa, J. C ardenas Gutierrez, J. Duarte Forero, Exergy, economic, and life-cycle assessment of ORC system for waste heat recovery in a natural gas internal combustion engine, Resources 9 (1) (2020) 2.
[62] Z. Zhang, X. Wang, X. Zhang, L. Jia, Optimizing the performance of a single PEM fuel cell, J. Fuel Cell Sci. Technol. 5 (3) (2008).
[63] A. Fontalvo, J. Solano, C. Pedraza, A. Bula, A. Gonzalez Quiroga, R. Vasquez Padilla, Energy, exergy and economic evaluation comparison of small-scale single and dual pressure organic rankine cycles integrated with low-grade heat sources, Entropy 19 (10) (2017) 476.
dc.rights.spa.fl_str_mv CC0 1.0 Universal
dc.rights.uri.spa.fl_str_mv http://creativecommons.org/publicdomain/zero/1.0/
dc.rights.accessrights.spa.fl_str_mv info:eu-repo/semantics/openAccess
dc.rights.coar.spa.fl_str_mv http://purl.org/coar/access_right/c_abf2
rights_invalid_str_mv CC0 1.0 Universal
http://creativecommons.org/publicdomain/zero/1.0/
http://purl.org/coar/access_right/c_abf2
eu_rights_str_mv openAccess
dc.format.mimetype.spa.fl_str_mv application/pdf
dc.publisher.spa.fl_str_mv Corporación Universidad de la Costa
dc.source.spa.fl_str_mv Heliyon
institution Corporación Universidad de la Costa
dc.source.url.spa.fl_str_mv https://www.sciencedirect.com/science/article/pii/S2405844021006095?via%3Dihub
bitstream.url.fl_str_mv https://repositorio.cuc.edu.co/bitstreams/94124f75-97cb-4e2b-996f-dc6206a530ab/download
https://repositorio.cuc.edu.co/bitstreams/dff04a24-585b-4f59-914d-7d0872640841/download
https://repositorio.cuc.edu.co/bitstreams/8b40e446-0d47-41f3-ac6a-ea9aa108109b/download
https://repositorio.cuc.edu.co/bitstreams/3dbf70ba-569b-4889-b747-f74ff4388862/download
https://repositorio.cuc.edu.co/bitstreams/16f40937-2a73-4eb0-8148-daddf03f66d7/download
bitstream.checksum.fl_str_mv 2156e0296442c475d4181cf54a4819be
42fd4ad1e89814f5e4a476b409eb708c
e30e9215131d99561d40d6b0abbe9bad
2bfc333415704dd14f5592973a5cf310
28ff31b818413e907e4b00d1e6069012
bitstream.checksumAlgorithm.fl_str_mv MD5
MD5
MD5
MD5
MD5
repository.name.fl_str_mv Repositorio de la Universidad de la Costa CUC
repository.mail.fl_str_mv repdigital@cuc.edu.co
_version_ 1811760761060458496
spelling Escobar Yonoff, RonyMaestre Cambronel, Daniel EstebanCharry, SebastiánRincón Montenegro, AdrianaPortnoy, Ivan2021-06-09T16:07:48Z2021-06-09T16:07:48Z20212405-8440https://hdl.handle.net/11323/8362https://doi.org/10.1016/j.heliyon.2021.e06506Corporación Universidad de la CostaREDICUC - Repositorio CUChttps://repositorio.cuc.edu.co/The study presents a complete one-dimensional model to evaluate the parameters that describe the operation of a Proton Exchange Membrane (PEM) electrolyzer and PEM fuel cell. The mathematical modeling is implemented in Matlab/Simulink® software to evaluate the influence of parameters such as temperature, pressure, and overpotentials on the overall performance. The models are further merged into an integrated electrolyzer-fuel cell system for electrical power generation. The operational description of the integrated system focuses on estimating the overall efficiency as a novel indicator. Additionally, the study presents an economic assessment to evaluate the cost-effectiveness based on different economic metrics such as capital cost, electricity cost, and payback period. The parametric analysis showed that as the temperature rises from 30 to 70 °C in both devices, the efficiency is improved between 5-20%. In contrast, pressure differences feature less relevance on the overall performance. Ohmic and activation overpotentials are highlighted for the highest impact on the generated and required voltage. Overall, the current density exhibited an inverse relation with the efficiency of both devices. The economic evaluation revealed that the integrated system can operate at variable load conditions while maintaining an electricity cost between 0.3-0.45 $/kWh. Also, the capital cost can be reduced up to 25% while operating at a low current density and maximum temperature. The payback period varies between 6-10 years for an operational temperature of 70 °C, which reinforces the viability of the system. Overall, hydrogen-powered systems stand as a promising technology to overcome energy transition as they provide robust operation from both energetic and economic viewpoints.Escobar Yonoff, Rony-will be generated-orcid-0000-0002-7214-8974-600Maestre Cambronel, Daniel Esteban-will be generated-orcid-0000-0002-0390-1555-600Charry, SebastiánRincón Montenegro, Adriana-will be generated-orcid-0000-0002-1324-9740-600Portnoy, Ivan-will be generated-orcid-0000-0002-7334-7596-600application/pdfengCorporación Universidad de la CostaCC0 1.0 Universalhttp://creativecommons.org/publicdomain/zero/1.0/info:eu-repo/semantics/openAccesshttp://purl.org/coar/access_right/c_abf2Heliyonhttps://www.sciencedirect.com/science/article/pii/S2405844021006095?via%3DihubElectrolyzerFuel cellEconomic assessmentProton exchange membraneElectric power generationPerformance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generationArtículo de revistahttp://purl.org/coar/resource_type/c_6501http://purl.org/coar/resource_type/c_2df8fbb1Textinfo:eu-repo/semantics/articlehttp://purl.org/redcol/resource_type/ARTinfo:eu-repo/semantics/acceptedVersion[1] G. Abu-Rumman, A.I. Khdair, S.I. Khdair, Current status and future investment potential in renewable energy in Jordan: an overview, Heliyon 6 (2) (2020), e03346.[2] G.V. Ochoa, C. Isaza-Roldan, J. Duarte Forero, Economic and exergo-advance analysis of a waste heat recovery system based on regenerative organic rankine cycle under organic fluids with low global warming potential, Energies 13 (6) (2020) 1317.[3] A. Ursúa, P. Sanchis, Static–dynamic modelling of the electrical behaviour of a commercial advanced alkaline water electrolyser, Int. J. Hydrogen Energy 37 (24) (2012) 18598–18614.[4] K. Zeng, D. Zhang, Recent progress in alkaline water electrolysis for hydrogen production and applications, Prog. Energy Combust. Sci. 36 (3) (2010) 307–326.[5] G. Amador, et al., Characteristics of auto-ignition in internal combustion engines operated with gaseous fuels of variable methane number, J. Energy Resour. Technol. 139 (2017).[6] J. Duarte Forero, G. Valencia Ochoa, J. Piero Rojas, Effect of the geometric profile of top ring on the tribological characteristics of a low-displacement diesel engine, Lubricants 8 (8) (2020) 83.[7] G. Valencia, C. Penaloza, J. Forero, Thermo-economic assessment of a gas ~ microturbine-absorption chiller trigeneration system under different compressor inlet air temperatures, Energies 12 (2019) 4643.[8] F. Guti errez-Martín, L. Amodio, M. Pagano, Hydrogen production by water electrolysis and off-grid solar PV, Int. J. Hydrogen Energy xxxx (2020).[9] M.H.S. Bargal, M.A.A. Abdelkareem, Q. Tao, J. Li, J. Shi, Y. Wang, Liquid cooling techniques in proton exchange membrane fuel cell stacks: a detailed survey, Alexandria Eng. J. 59 (2) (2020) 635–655.[10] R.E. Yonoff, G.V. Ochoa, Y. Cardenas-Escorcia, J.I. Silva-Ortega, L. Merino-Stand, ~ Research trends in proton exchange membrane fuel cells during 2008–2018: a bibliometric analysis, Heliyon 5 (5) (2019), e01724.[11] M. Abdollahzadeh, P. Ribeirinha, M. Boaventura, A. Mendes, Three-dimensional modeling of PEMFC with contaminated anode fuel, Energy 152 (2018) 939–959.[12] M. Sahraoui, Y. Bichiou, K. Halouani, Three-dimensional modeling of water transport in PEMFC, Int. J. Hydrogen Energy 38 (2012).[13] J.-P. Kone, X. Zhang, Y. Yan, G. Hu, G. Ahmadi, Three-dimensional multiphase flow computational fluid dynamics models for proton exchange membrane fuel cell: a theoretical development, J. Comput. Multiph. Flows 9 (2017), 1757482X1769234.[14] K. Shekhar, An Investigation into the Minimum Dimensionality Required for Accurate Simulation of Proton Exchange Membrane Fuel Cells by the Comparison between 1- and 3-dimension Models, 2013.[15] Z. Abdin, C.J. Webb, E.M. Gray, PEM fuel cell model and simulation in Matlab–Simulink based on physical parameters, Energy 116 (2016) 1131–1144.[16] S.L. Chavan, D.B. Talange, Modeling and performance evaluation of PEM fuel cell by controlling its input parameters, Energy 138 (2017) 437–445.[17] T. Yigit, O.F. Selamet, Mathematical modeling and dynamic Simulink simulation of high-pressure PEM electrolyzer system, Int. J. Hydrogen Energy 41 (32) (2016) 13901–13914.[18] Z. Abdin, C.J. Webb, E.M. Gray, Modelling and simulation of an alkaline electrolyser cell, Energy 138 (2017) 316–331.[19] B. Han, S.M. Steen, J. Mo, F.-Y. Zhang, Electrochemical performance modeling of a proton exchange membrane electrolyzer cell for hydrogen energy, Int. J. Hydrogen Energy 40 (22) (2015) 7006–7016.[20] M. Alibaba, R. Pourdarbani, M.H.K. Manesh, G.V. Ochoa, J.D. Forero, Thermodynamic, exergo-economic and exergo-environmental analysis of hybrid geothermal-solar power plant based on ORC cycle using emergy concept, Heliyon 6 (4) (2020), e03758.[21] K. Moorthy, N. Patwa, Y. Gupta, et al., Breaking barriers in deployment of renewable energy, Heliyon 5 (1) (2019), e01166.[22] F. Alshehri, V.G. Su arez, J.L. Rueda Torres, A. Perilla, M.A.M.M. van der Meijden, Modelling and evaluation of PEM hydrogen technologies for frequency ancillary services in future multi-energy sustainable power systems, Heliyon 5 (4) (2019), e01396.[23] C.A. Frangopoulos, L.G. Nakos, Development of a model for thermoeconomic design and operation optimization of a PEM fuel cell system, Energy 31 (10–11) (2006) 1501–1519.[24] A.A. AlZahrani, I. Dincer, Exergoeconomic analysis of hydrogen production using a standalone high-temperature electrolyzer, Int. J. Hydrogen Energy xxxx (2020).[25] T. Taner, S.A.H. Naqvi, M. Ozkaymak, Techno-economic analysis of a more efficient hydrogen generation system prototype: a case study of PEM electrolyzer with Cr-C coated SS304 bipolar plates, Fuel Cells 19 (1) (2019) 19–26.[26] E.I. Zoulias, N. Lymberopoulos, Techno-economic analysis of the integration of hydrogen energy technologies in renewable energy-based stand-alone power systems, Renew. Energy 32 (4) (2007) 680–696.[27] M. Thema, F. Bauer, M. Sterner, Power-to-Gas: electrolysis and methanation status review, Renew. Sustain. Energy Rev. 112 (Sep-2019) 775–787. Elsevier Ltd.[28] H. Steeb, W. Seeger, H. Aba Oud, Hysolar: an overview on the German-Saudi Arabian programme on solar hydrogen, Int. J. Hydrogen Energy 19 (8) (1994) 683–686.[29] T. Lepage, M. Kammoun, Q. Schmetz, A. Richel, Biomass-to-hydrogen: a review of main routes production, processes evaluation and techno-economical assessment, Biomass Bioenergy 144 (Jan-2021) 105920. Elsevier Ltd.[30] D. Milani, A. Kiani, R. McNaughton, Renewable-powered hydrogen economy from Australia’s perspective, Int. J. Hydrogen Energy 45 (46) (2020) 24125–24145.[31] I. Dincer, C. Acar, Review and evaluation of hydrogen production methods for better sustainability, Int. J. Hydrogen Energy 40 (34) (2014) 11094–11111.[32] K.K.T. Thanapalan, J.G. Williams, G.P. Liu, D. Rees, Modelling OF a PEM fuel cell system, IFAC Proc. Vol. 41 (2) (2008) 4636–4641.[33] T. Mennola, et al., Mass transport in the cathode of a free-breathing polymer electrolyte membrane fuel cell, J. Appl. Electrochem. 33 (11) (2003) 979–987.[34] H. Pukrushpan, T. Jay, Anna G. Stefanopoulou, Peng, Control of Fuel Cell Power Systems, Springer, 2004.[35] J.H. Nam, M. Kaviany, Effective diffusivity and water-saturation distribution in single- and two-layer PEMFC diffusion medium, Int. J. Heat Mass Tran. 46 (24) (2003) 4595–4611.[36] R. García-Valverde, N. Espinosa, A. Urbina, Simple PEM water electrolyser model and experimental validation, Int. J. Hydrogen Energy 37 (2) (2012) 1927–1938.[37] H. Gorgün, Dynamic modelling of a proton exchange membrane (PEM) electrolyzer, € Int. J. Hydrogen Energy 31 (1) (2006) 29–38.[38] K.S. V Santhanam, R.J. Press, M.J. Miri, A. V Bailey, G.A. Takacs, Introduction to Hydrogen Technology, Wiley, 2017.[39] C. Vallieres, D. Winkelmann, D. Roizard, E. Favre, P. Scharfer, M. Kind, On Schroeder’s paradox, J. Membr. Sci. 278 (1) (2006) 357–364.[40] L. Onishi, J. Prausnitz, WaterNafion equilibria. Absence of Schroeder’s paradox, J. Phys. Chem. B 111 (2007) 10166–10173.[41] T.A. Zawodzinski, M. Neeman, L.O. Sillerud, S. Gottesfeld, Determination of water diffusion coefficients in perfluorosulfonate ionomeric membranes, J. Phys. Chem. 95 (15) (1991) 6040–6044.[42] F. Marangio, M. Santarelli, M. Calì, Theoretical model and experimental analysis of a high pressure PEM water electrolyser for hydrogen production, Int. J. Hydrogen Energy 34 (3) (2009) 1143–1158.[43] D.J. Kim, M.J. Jo, S.Y. Nam, A review of polymer–nanocomposite electrolyte membranes for fuel cell application, J. Ind. Eng. Chem. 21 (2015) 36–52.[44] J. Qi, Y. Zhai, J. St-Pierre, Effect of contaminant mixtures in air on proton exchange membrane fuel cell performance, J. Power Sources 413 (2019) 86–97.[45] J. Milewski, G. Guandalini, S. Campanari, Modeling an alkaline electrolysis cell through reduced-order and loss-estimate approaches, J. Power Sources 269 (2014) 203–211.[46] P.D. Beattie, V.I. Basura, S. Holdcroft, Temperature and pressure dependence of O2 reduction at Pt∣Nafion® 117 and Pt∣BAM® 407 interfaces, J. Electroanal. Chem. 468 (2) (1999) 180–192.[47] N.M. Markovi c, B.N. Grgur, P.N. Ross, Temperature-dependent hydrogen electrochemistry on platinum low-index single-crystal surfaces in acid solutions, J. Phys. Chem. B 101 (27) (1997) 5405–5413.[48] M.G. Santarelli, M.F. Torchio, P. Cochis, Parameters estimation of a PEM fuel cell polarization curve and analysis of their behavior with temperature, J. Power Sources 159 (2) (2006) 824–835.[49] T.E. Springer, T.A. Zawodzinski, S. Gottesfeld, Polymer electrolyte fuel cell model, J. Electrochem. Soc. 138 (8) (1991) 2334–2342.[50] F. Barbir, Fuel cell electrochemistry, in: PEM Fuel Cells: Theory and Practice, Academic Press, Burlington, 2005, pp. 33–72.[51] R.M. Dell, P.T. Moseley, D.A.J. Rand, Hydrogen, fuel cells and fuel cell vehicles, in: Towards sustainable road transport, Academic Press, Boston, 2014, pp. 260–295.[52] F. Barbir, T. Gomez, Ef ficiency and economics of proton exchange membrane (PEM) fuel cells, Int. J. Hydrogen Energy 22 (10–11) (1997) 1027–1037.[53] F. Barbir, Fuel cell applications, in: F. Barbir (Ed.), PEM Fuel Cells, second ed., Academic Press, Boston, 2013, pp. 373–434.[54] L. Zhou, Progress and problems in hydrogen storage methods, Renew. Sustain. Energy Rev. 9 (4) (Aug-2005) 395–408. Elsevier Ltd.[55] S.K. Kamarudin, W.R.W. Daud, A. Md. Som, M.S. Takriff, A.W. Mohammad, Technical design and economic evaluation of a PEM fuel cell system, J. Power Sources 157 (2) (2006) 641–649.[56] S. Rahimi, M. Meratizaman, S. Monadizadeh, M. Amidpour, Techno-economic analysis of wind turbine-PEM (polymer electrolyte membrane) fuel cell hybrid system in standalone area, Energy 67 (2014) 381–396.[57] A. Mayyas, et al., Manufacturing cost analysis for proton exchange membrane water electrolyzers manufacturing cost analysis for proton exchange membrane water electrolyzers, Natl. Renew. Energy Lab. (2019) 65. August.[58] R. Yukesh Kannah, et al., Techno-economic assessment of various hydrogen production methods – A review, Bioresour. Technol. 319 (Jan-2021) 124175. Elsevier Ltd.[59] G. Valencia Ochoa, C. Acevedo Penaloza, J. Duarte Forero, Thermoeconomic ~ optimization with PSO algorithm of waste heat recovery systems based on organic rankine cycle system for a natural gas engine, Energies 12 (21) (2019) 4165.[60] F. Consuegra, A. Bula, W. Guillín, J. S anchez, J. Duarte Forero, Instantaneous incylinder volume considering deformation and clearance due to lubricating film in reciprocating internal combustion engines, Energies 12 (8) (2019) 1437.[61] G. Valencia Ochoa, J. C ardenas Gutierrez, J. Duarte Forero, Exergy, economic, and life-cycle assessment of ORC system for waste heat recovery in a natural gas internal combustion engine, Resources 9 (1) (2020) 2.[62] Z. Zhang, X. Wang, X. Zhang, L. Jia, Optimizing the performance of a single PEM fuel cell, J. Fuel Cell Sci. Technol. 5 (3) (2008).[63] A. Fontalvo, J. Solano, C. Pedraza, A. Bula, A. Gonzalez Quiroga, R. Vasquez Padilla, Energy, exergy and economic evaluation comparison of small-scale single and dual pressure organic rankine cycles integrated with low-grade heat sources, Entropy 19 (10) (2017) 476.PublicationORIGINALPerformance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generation.pdfPerformance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generation.pdfapplication/pdf3834056https://repositorio.cuc.edu.co/bitstreams/94124f75-97cb-4e2b-996f-dc6206a530ab/download2156e0296442c475d4181cf54a4819beMD51CC-LICENSElicense_rdflicense_rdfapplication/rdf+xml; charset=utf-8701https://repositorio.cuc.edu.co/bitstreams/dff04a24-585b-4f59-914d-7d0872640841/download42fd4ad1e89814f5e4a476b409eb708cMD52LICENSElicense.txtlicense.txttext/plain; charset=utf-83196https://repositorio.cuc.edu.co/bitstreams/8b40e446-0d47-41f3-ac6a-ea9aa108109b/downloade30e9215131d99561d40d6b0abbe9badMD53THUMBNAILPerformance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generation.pdf.jpgPerformance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generation.pdf.jpgimage/jpeg62838https://repositorio.cuc.edu.co/bitstreams/3dbf70ba-569b-4889-b747-f74ff4388862/download2bfc333415704dd14f5592973a5cf310MD54TEXTPerformance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generation.pdf.txtPerformance assessment and economic perspectives of integrated PEM fuel cell and PEM electrolyzer for electric power generation.pdf.txttext/plain76526https://repositorio.cuc.edu.co/bitstreams/16f40937-2a73-4eb0-8148-daddf03f66d7/download28ff31b818413e907e4b00d1e6069012MD5511323/8362oai:repositorio.cuc.edu.co:11323/83622024-09-17 11:01:51.139http://creativecommons.org/publicdomain/zero/1.0/CC0 1.0 Universalopen.accesshttps://repositorio.cuc.edu.coRepositorio de la Universidad de la Costa CUCrepdigital@cuc.edu.coQXV0b3Jpem8gKGF1dG9yaXphbW9zKSBhIGxhIEJpYmxpb3RlY2EgZGUgbGEgSW5zdGl0dWNpw7NuIHBhcmEgcXVlIGluY2x1eWEgdW5hIGNvcGlhLCBpbmRleGUgeSBkaXZ1bGd1ZSBlbiBlbCBSZXBvc2l0b3JpbyBJbnN0aXR1Y2lvbmFsLCBsYSBvYnJhIG1lbmNpb25hZGEgY29uIGVsIGZpbiBkZSBmYWNpbGl0YXIgbG9zIHByb2Nlc29zIGRlIHZpc2liaWxpZGFkIGUgaW1wYWN0byBkZSBsYSBtaXNtYSwgY29uZm9ybWUgYSBsb3MgZGVyZWNob3MgcGF0cmltb25pYWxlcyBxdWUgbWUobm9zKSBjb3JyZXNwb25kZShuKSB5IHF1ZSBpbmNsdXllbjogbGEgcmVwcm9kdWNjacOzbiwgY29tdW5pY2FjacOzbiBww7pibGljYSwgZGlzdHJpYnVjacOzbiBhbCBww7pibGljbywgdHJhbnNmb3JtYWNpw7NuLCBkZSBjb25mb3JtaWRhZCBjb24gbGEgbm9ybWF0aXZpZGFkIHZpZ2VudGUgc29icmUgZGVyZWNob3MgZGUgYXV0b3IgeSBkZXJlY2hvcyBjb25leG9zIHJlZmVyaWRvcyBlbiBhcnQuIDIsIDEyLCAzMCAobW9kaWZpY2FkbyBwb3IgZWwgYXJ0IDUgZGUgbGEgbGV5IDE1MjAvMjAxMiksIHkgNzIgZGUgbGEgbGV5IDIzIGRlIGRlIDE5ODIsIExleSA0NCBkZSAxOTkzLCBhcnQuIDQgeSAxMSBEZWNpc2nDs24gQW5kaW5hIDM1MSBkZSAxOTkzIGFydC4gMTEsIERlY3JldG8gNDYwIGRlIDE5OTUsIENpcmN1bGFyIE5vIDA2LzIwMDIgZGUgbGEgRGlyZWNjacOzbiBOYWNpb25hbCBkZSBEZXJlY2hvcyBkZSBhdXRvciwgYXJ0LiAxNSBMZXkgMTUyMCBkZSAyMDEyLCBsYSBMZXkgMTkxNSBkZSAyMDE4IHkgZGVtw6FzIG5vcm1hcyBzb2JyZSBsYSBtYXRlcmlhLg0KDQpBbCByZXNwZWN0byBjb21vIEF1dG9yKGVzKSBtYW5pZmVzdGFtb3MgY29ub2NlciBxdWU6DQoNCi0gTGEgYXV0b3JpemFjacOzbiBlcyBkZSBjYXLDoWN0ZXIgbm8gZXhjbHVzaXZhIHkgbGltaXRhZGEsIGVzdG8gaW1wbGljYSBxdWUgbGEgbGljZW5jaWEgdGllbmUgdW5hIHZpZ2VuY2lhLCBxdWUgbm8gZXMgcGVycGV0dWEgeSBxdWUgZWwgYXV0b3IgcHVlZGUgcHVibGljYXIgbyBkaWZ1bmRpciBzdSBvYnJhIGVuIGN1YWxxdWllciBvdHJvIG1lZGlvLCBhc8OtIGNvbW8gbGxldmFyIGEgY2FibyBjdWFscXVpZXIgdGlwbyBkZSBhY2Npw7NuIHNvYnJlIGVsIGRvY3VtZW50by4NCg0KLSBMYSBhdXRvcml6YWNpw7NuIHRlbmRyw6EgdW5hIHZpZ2VuY2lhIGRlIGNpbmNvIGHDsW9zIGEgcGFydGlyIGRlbCBtb21lbnRvIGRlIGxhIGluY2x1c2nDs24gZGUgbGEgb2JyYSBlbiBlbCByZXBvc2l0b3JpbywgcHJvcnJvZ2FibGUgaW5kZWZpbmlkYW1lbnRlIHBvciBlbCB0aWVtcG8gZGUgZHVyYWNpw7NuIGRlIGxvcyBkZXJlY2hvcyBwYXRyaW1vbmlhbGVzIGRlbCBhdXRvciB5IHBvZHLDoSBkYXJzZSBwb3IgdGVybWluYWRhIHVuYSB2ZXogZWwgYXV0b3IgbG8gbWFuaWZpZXN0ZSBwb3IgZXNjcml0byBhIGxhIGluc3RpdHVjacOzbiwgY29uIGxhIHNhbHZlZGFkIGRlIHF1ZSBsYSBvYnJhIGVzIGRpZnVuZGlkYSBnbG9iYWxtZW50ZSB5IGNvc2VjaGFkYSBwb3IgZGlmZXJlbnRlcyBidXNjYWRvcmVzIHkvbyByZXBvc2l0b3Jpb3MgZW4gSW50ZXJuZXQgbG8gcXVlIG5vIGdhcmFudGl6YSBxdWUgbGEgb2JyYSBwdWVkYSBzZXIgcmV0aXJhZGEgZGUgbWFuZXJhIGlubWVkaWF0YSBkZSBvdHJvcyBzaXN0ZW1hcyBkZSBpbmZvcm1hY2nDs24gZW4gbG9zIHF1ZSBzZSBoYXlhIGluZGV4YWRvLCBkaWZlcmVudGVzIGFsIHJlcG9zaXRvcmlvIGluc3RpdHVjaW9uYWwgZGUgbGEgSW5zdGl0dWNpw7NuLCBkZSBtYW5lcmEgcXVlIGVsIGF1dG9yKHJlcykgdGVuZHLDoW4gcXVlIHNvbGljaXRhciBsYSByZXRpcmFkYSBkZSBzdSBvYnJhIGRpcmVjdGFtZW50ZSBhIG90cm9zIHNpc3RlbWFzIGRlIGluZm9ybWFjacOzbiBkaXN0aW50b3MgYWwgZGUgbGEgSW5zdGl0dWNpw7NuIHNpIGRlc2VhIHF1ZSBzdSBvYnJhIHNlYSByZXRpcmFkYSBkZSBpbm1lZGlhdG8uDQoNCi0gTGEgYXV0b3JpemFjacOzbiBkZSBwdWJsaWNhY2nDs24gY29tcHJlbmRlIGVsIGZvcm1hdG8gb3JpZ2luYWwgZGUgbGEgb2JyYSB5IHRvZG9zIGxvcyBkZW3DoXMgcXVlIHNlIHJlcXVpZXJhIHBhcmEgc3UgcHVibGljYWNpw7NuIGVuIGVsIHJlcG9zaXRvcmlvLiBJZ3VhbG1lbnRlLCBsYSBhdXRvcml6YWNpw7NuIHBlcm1pdGUgYSBsYSBpbnN0aXR1Y2nDs24gZWwgY2FtYmlvIGRlIHNvcG9ydGUgZGUgbGEgb2JyYSBjb24gZmluZXMgZGUgcHJlc2VydmFjacOzbiAoaW1wcmVzbywgZWxlY3Ryw7NuaWNvLCBkaWdpdGFsLCBJbnRlcm5ldCwgaW50cmFuZXQsIG8gY3VhbHF1aWVyIG90cm8gZm9ybWF0byBjb25vY2lkbyBvIHBvciBjb25vY2VyKS4NCg0KLSBMYSBhdXRvcml6YWNpw7NuIGVzIGdyYXR1aXRhIHkgc2UgcmVudW5jaWEgYSByZWNpYmlyIGN1YWxxdWllciByZW11bmVyYWNpw7NuIHBvciBsb3MgdXNvcyBkZSBsYSBvYnJhLCBkZSBhY3VlcmRvIGNvbiBsYSBsaWNlbmNpYSBlc3RhYmxlY2lkYSBlbiBlc3RhIGF1dG9yaXphY2nDs24uDQoNCi0gQWwgZmlybWFyIGVzdGEgYXV0b3JpemFjacOzbiwgc2UgbWFuaWZpZXN0YSBxdWUgbGEgb2JyYSBlcyBvcmlnaW5hbCB5IG5vIGV4aXN0ZSBlbiBlbGxhIG5pbmd1bmEgdmlvbGFjacOzbiBhIGxvcyBkZXJlY2hvcyBkZSBhdXRvciBkZSB0ZXJjZXJvcy4gRW4gY2FzbyBkZSBxdWUgZWwgdHJhYmFqbyBoYXlhIHNpZG8gZmluYW5jaWFkbyBwb3IgdGVyY2Vyb3MgZWwgbyBsb3MgYXV0b3JlcyBhc3VtZW4gbGEgcmVzcG9uc2FiaWxpZGFkIGRlbCBjdW1wbGltaWVudG8gZGUgbG9zIGFjdWVyZG9zIGVzdGFibGVjaWRvcyBzb2JyZSBsb3MgZGVyZWNob3MgcGF0cmltb25pYWxlcyBkZSBsYSBvYnJhIGNvbiBkaWNobyB0ZXJjZXJvLg0KDQotIEZyZW50ZSBhIGN1YWxxdWllciByZWNsYW1hY2nDs24gcG9yIHRlcmNlcm9zLCBlbCBvIGxvcyBhdXRvcmVzIHNlcsOhbiByZXNwb25zYWJsZXMsIGVuIG5pbmfDum4gY2FzbyBsYSByZXNwb25zYWJpbGlkYWQgc2Vyw6EgYXN1bWlkYSBwb3IgbGEgaW5zdGl0dWNpw7NuLg0KDQotIENvbiBsYSBhdXRvcml6YWNpw7NuLCBsYSBpbnN0aXR1Y2nDs24gcHVlZGUgZGlmdW5kaXIgbGEgb2JyYSBlbiDDrW5kaWNlcywgYnVzY2Fkb3JlcyB5IG90cm9zIHNpc3RlbWFzIGRlIGluZm9ybWFjacOzbiBxdWUgZmF2b3JlemNhbiBzdSB2aXNpYmlsaWRhZA==