Experimental observations on hot-spots and derived

Moreton Villagra, Rodrigo and Lorenzo Pigueiras, Eduardo and Narvarte Fernández, Luis (2015). Experimental observations on hot-spots and derived. "Solar Energy", v. 118 ; pp. 28-40. ISSN 0927-0248.


Title: Experimental observations on hot-spots and derived
  • Moreton Villagra, Rodrigo
  • Lorenzo Pigueiras, Eduardo
  • Narvarte Fernández, Luis
Item Type: Article
Título de Revista/Publicación: Solar Energy
Date: August 2015
Volume: 118
Freetext Keywords: Hot-spot; PV module lifetime; PV module efficiency; Operation losses
Faculty: Instituto de Energía Solar (IES) (UPM)
Department: Electrónica Física
Creative Commons Licenses: Recognition - No derivative works - Non commercial

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The hot-spot phenomenon is a relatively frequent problem occurring in current photovoltaic generators. It entails both a risk for the photovoltaic module’s lifetime and a decrease in its operational efficiency. Nevertheless, there is still a lack of widely accepted procedures for dealing with them in practice. This paper presents the IES–UPM observations on 200 affected photovoltaic modules. Visual and infrared inspection, as well as electroluminescence, peak power rating and operating voltage tests have been carried out. Thermography under steady state conditions and photovoltaic module operating voltage, both at normal photovoltaic system operating conditions, are the selected methods to deal in practice with hot-spots. The temperature difference between the hot-spot and its surroundings, and the operating voltage differences between affected and non-affected photovoltaic modules are the base for establishing defective criteria, at the lights of both lifetime and operating efficiency considerations. Hot-spots temperature gradients larger than 20 °C, in any case, and larger than 10 °C when, at the same time, voltage operating losses are larger than the allowable power losses fixed at the photovoltaic module warranties, are proposed as rejecting conditions for routine inspections under contractual frameworks. The upper threshold of 20 °C is deduced for temperate climates from the basic criterion of keeping absolute hot-spot temperatures below 20 °C.

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Item ID: 36395
DC Identifier: http://oa.upm.es/36395/
OAI Identifier: oai:oa.upm.es:36395
Deposited by: Memoria Investigacion
Deposited on: 02 Dec 2015 19:00
Last Modified: 02 Dec 2015 19:00
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