Salt hydrates as phase change materials for photovoltaics thermal management

Abstract

Conventional source of energy, for example fossil fuels, are depleting with time. The combustion of fossil fuels also lead to increased carbon emission in environment, causing global warming. To meet the world's increasing energy demand, the utilization of alternative resources like solar energy must be improved. Solar energy can be harvested directly into electricity by using photovoltaic (PV) module. However, when the solar radiation reaches a PV module, it is not only converted into electricity but also into thermal energy, which increases the PV system temperature. 1 There are many factors affecting the solar power output of the PV system. Temperature is one of them. The productivity of a PV-module is the inverse of the temperature. According to the Standard Test Conditions, if a PV module is operated at temperature higher than the ambient temperature, 25°C, at each increase of degree Celsius, the conversion rate of the PV module decreases, up to 0.5%. 2 As expected, summer is the season with the highest solar radiation, when a PV system such as solar panel can absorb most solar energy and produce heat or electricity

Form‐stable phase change materials supported by nanostructured zinc polyacrylate weakening super cooling of polyethylene glycol

“…12 PCMs can be divided into three categories, namely, organic and inorganic ones, and eutectics. 13,14 The organic PCMs mainly include alkanes, fatty acids and fatty alcohols. 15,16 As one of the most important organic PCMs, polyethylene glycol (PEG) has been studied and utilized for thermal energy storage 17 and life science applications, 18 in virtue of its unique advantages including non-toxicity, biocompatibility, suitable phase change temperature and chemical reactivity with specific reagents.…”

“…PCMs can be divided into three categories, namely, organic and inorganic ones, and eutectics 13,14 . The organic PCMs mainly include alkanes, fatty acids and fatty alcohols 15,16 .…”

The Potential Environmental and Social Influence of the Inorganic Salt Hydrates Used as a Phase Change Material for Thermal Energy Storage in Solar Installations

“…One of the groups of phase change materials that are used in solar installations includes inorganic salts [8]. Inorganic salts, as opposed to organic ones, are considered more environmentally friendly and safe [9], have a higher volumetric latent heat, are cheaper, more easily available, their thermal conductivity is higher, they have lower volumetric changes, and they are a non-flammable material.…”

“…Inorganic salts, as opposed to organic ones, are considered more environmentally friendly and safe [9], have a higher volumetric latent heat, are cheaper, more easily available, their thermal conductivity is higher, they have lower volumetric changes, and they are a non-flammable material. However, the disadvantage is that they are corrosive, they are subject to overcooling, and the volume changes are high [8]. Taking care of the technical and economic aspects, there are works devoted to improving the properties of salt hydrates.…”

“…The article reviews, from the point of view of environmental risks, the eight considered to be the most promising inorganic salt hydrates used in solar installations [8][9][10][11][12]. They are magnesium chloride hexahydrate, magnesium nitrate hexahydrate, sodium sulfate decahydrate, sodium acetate trihydrate, sodium carbonate decahydrate, calcium chloride hexahydrate, disodium hydrogen phosphate dodecahydrate, and barium hydroxide octahydrate.…”