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Contents lists available at ScienceDirectSolar Energyjournal homepage: www.elsevier.com/locate/solenerAssessment of thermal performance of PCM in latent heat storage system fordif f erent applicationsNidal H. Abu-Hamdeh ? , Khaled A. AlnefaieMechanical Engineering Department, Faculty of Engineering, King Abdulaziz University, P.O. Box 40844, Jeddah 21511, Saudi ArabiaA R T I C L E I N F OKeywords:Parabolic solar heat collectorPhase change materialSolar stoveThermal performanceA B S T R A C TThis article demonstrates the feasibility of using a phase change material (PCM) in a solar stove for storingenergy. The PCM is a material that is able of absorbing and liberating great amounts of energy upon solidif i -cation and melting due to its superior latent heat storage capability. In this study, small capsules, used as PCMstorage units in the solar stove, were constructed from aluminum and tested for solar energy storage during shinydays. The capsules were placed in a receiver of a parabolic ref l ector to absorb heat from the ref l ected sunlight ofthe parabolic ref l ector, which was stored as latent heat in the PCM. Acetamide of commercial grade was used asthe material for latent heat storage. The solar stove with the PCM storage units had been experimentally tested.The thermal performance was analyzed during idle condition of the fan and at three rates of air f l ow. Thetemperature of the PCM capsules decreased rapidly during the f i rst few minutes as the temperature of cookingpan increased at the same rate, and then the two temperatures matched and decreased slowly. The rate of changewas higher with increasing air f l ow rate. Energy ef f ectiveness between the PCM tubes and air f l ow increasedwith increasing air f l ow rate. The results supply signif i cant information to design a prototype of solar stoveprovided with a good thermal performance material utilized for storing thermal energy.1. IntroductionSolar energy has many applications and uses including lighting andair-conditioning of buildings, generating electricity, and supplying hotwater. Solar radiation is progressively becoming respected for its im-pact on living material and the probability of its application for valu-able intentions. It is a continuous supply of renewable energy that has avast capacity for a widespread range of uses since it is plentiful andwithin reach. It is speedily earning base as a complement to the limitednonrenewable supplies of energy.Water heating and space conditioning are well known applicationsof solar energy. Recently, more applications of solar energy were cre-ated and developed including solar cooking. Solar stove technologytransforms the sunlight energy into thermal energy, an energy whichdoes not consume fossil fuels and does not produce any pollution, andmost importantly it lasts for long time with very slight maintenance.The energy from the sun has many applications nowadays because it isa reliable source of fuel with no accompanying conveyance complica-tions or storage problems. Solar cooking among these attractive appli-cations of the solar energy that can save time, work and fuel and it isenvironmentally friendly.A solar stove is simply an appliance that employs solar energy forfood cooking. The main principle of the solar stove is as follows.Capsules f i lled with phase change material (PCM) absorb heat energywhen they are exposed to concentrated sun rays in a receiver. As aresult, their temperature increase and the PCM liquefy as time passes.Eventually, the PCM will be completely in liquid state. At this point,energy is stored in the PCM and capsules are ready to be moved to asolar stove. In the stove, the temperature of the PCM will fall as heatenergy is released back gradually into environment. The heat releasedfrom the PCM in the stove is used for cooking. Solar stoves or solarcookers are constantly developed by manufacturers and researchers.For example, Joshi et al. (2012a,b) aimed to increase the solar cookingef f i ciency to more than 60% through providing an ef f i cient design toaccomplish that. In their experiments, the cooking vessels obtainedenergy by means of natural convection through condensing steam on anoutside surface. Kumar et al. (2011) performed an exergy and energyef f i ciencies of a box type solar cooker of trimmed pyramid kind. Theycalculated a maximum energy obtained by water of 20.8 kJ and aminimum energy of 7.5 kJ within the solar cooker. The analysis of ex-ergy of their cookers was reasonable and an inclusive mean for theperformance assessment of solar cookers. Al-Soud et al. (2010) in-vestigated a sun tracking technique that operates with two axes para-bolic cooker. A 90°C cooker’s water temperature was obtained whereashttps://doi.org/10.1016/j.solener.2018.11.035Received 11 August 2018; Received in revised form 25 October 2018; Accepted 14 November 2018? Corresponding author.E-mail addresses: nabuhamdeh@kau.edu.sa (N.H. Abu-Hamdeh), kalnefaie@kau.edu.sa (K.A. Alnefaie).Solar Energy 177 (2019) 317–323Available online 19 November 20180038-092X/ © 2018 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/BY-NC-ND/4.0/).T