Improving the efficiency of solar photovoltaics by means of geothermal cooling: a year-long test campaign

Heating up of photovoltaic modules during operation results in a significant power output reduction. This effect is especially relevant in regions with the highest photovoltaic potential, where irradiance and ambient temperature are particularly high. In this paper, a novel low enthalpy geothermal c...

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Detalles Bibliográficos
Autores: López Pascual, Diego|||0000-0002-2485-2297, Valiente Blanco, Ignacio|||0000-0001-5068-7910, Fernández Muñoz, Miguel|||0000-0001-8872-7834, Díez Jiménez, Efrén|||0000-0002-3689-841X
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universidad de Alcalá (UAH)
Repositorio:e_Buah Biblioteca Digital Universidad de Alcalá
Idioma:inglés
OAI Identifier:oai:dnet:ebuahbibliot::9ab5160ef3e9a1e016867844846fa067
Acceso en línea:http://hdl.handle.net/10017/66682
https://dx.doi.org/10.1016/j.renene.2024.120553
Access Level:acceso abierto
Palabra clave:Geothermal cooling
Photovoltaics
Efficiency improvement
Active cooling
Energías Renovables/Energías Alternativas
Alternative energies
Descripción
Sumario:Heating up of photovoltaic modules during operation results in a significant power output reduction. This effect is especially relevant in regions with the highest photovoltaic potential, where irradiance and ambient temperature are particularly high. In this paper, a novel low enthalpy geothermal cooling system that improves the efficiency of a commercial solar module is described and experimentally validated. Two heat exchangers, one attached to the backside of the module, and another introduced inside a 15 m deep borehole, are connected in a closed circuit. A water-based coolant is pumped through the system, evacuating the excess heat from the module, and dissipating it underground in a clean and efficient manner, without additional water consumption after filling the system. The performance of the cooling system was experimentally tested by implementing it, for the first time, in a single-axis solar tracking isolated photovoltaic facility. Extensive tests were carried out in Spain, between September 2021 and August 2022 under a wide variety of environmental conditions. The efficiency improvement system has demonstrated its technical feasibility over a one-year period, showing a peak net efficiency improvement up to 13.4 %. Moreover, a positive net efficiency improvement has been demonstrated all year long, even during the winter months.