Solar Thermal Energy Storage System Using Phase Change Material For Uninterrupted On Farm Agricultural Processing And Value Addition

Thermal energy storage technologies are gaining attention nowadays for uninterrupted supply of solar power in off-sunshine hours. An indigenized solar phase change material (PCM) system was developed and performance evaluated in the current study to efficiently store solar thermal power using a latent heat storage approach, which can be utilized in any subsequent decentralized food processing application. A 2.5 m2 laying Scheffler reflector is used to precisely focus the incoming direct normal irradiance (DNI) on a casted aluminum heat receiver (220 mm diameter) from where this concentrated heat energy is absorbed and conducted to the PCM unit by the flow of thermal oil (Fragoltherm-32 thermo-oil). During the circulation around PCM pipes inside the PCM unit, thermal oil discharges heat energy to the PCM, which undergoes change of phase from solid to liquid. Computational fluid dynamics (CFD) analysis of the PCM unit were also performed according to the actual boundary conditions, which gave satisfactory results in terms of temperature and velocity distribution. With an average DNI of 781 W/m2, the highest temperature of the receiver surface during the trials was observed at about 155 C that produces thermal oil at 110°C inside the receiver and around 48°C of PCM in the PCM unit. The heat energy losses per unit time (W) due to the lack of reflectivity from the Scheffler reflector, out-of-focus radiations at the targeted area, absorptivity of heat receiver, piping system losses, and cylinder losses (in the form of conduction, convection, and radiations using 50 mm insulation thickness) were found to be 110 W (10 %), 99 W (9 %), 89 W (8 %), 128 W (12 %), 161 W (15 %), and 89 W (8 %), respectively. These findings of CFD analysis and mathematical modeling were also consistent with real-time data, which was logged through an online Control and Monitoring Interface portal. The final energy available to the PCM was 414W with an overall system efficiency of 38 %, which can be improved by decreasing thermal losses of the system and using other PCM materials.

This book focuses on latent heat storage, which is one of the most efficient ways of storing thermal energy. Unlike the sensible heat storage method, the latent heat storage method provides much higher storage density with a smaller difference between storing and releasing temperatures. Thermal Energy Storage with Phase Change Materials is structured into four chapters that cover many aspects of thermal energy storage and their practical applications. Chapter 1 reviews selection, performance, and applications of phase change materials. Chapter 2 investigates mathematical analyses of phase change processes. Chapters 3 and 4 present passive and active applications for energy saving, peak load shifting, and price-based control heating using phase change materials. These chapters explore the hot topic of energy saving in an overarching way, and so they are relevant to all courses. This book is an ideal research reference for students at the postgraduate level. It also serves as a useful reference for electrical, mechanical, and chemical engineers and students throughout their work. FEATURES Explains the technical principles of thermal energy storage, including materials and applications in different classifications Provides fundamental calculations of heat transfer with phase change Discusses the benefits and limitations of different types of phase change materials (PCM) in both micro- and macroencapsulations Reviews the mechanisms and applications of available thermal energy storage systems Introduces innovative solutions in hot and cold storage applications

Energy Storage not only plays an important role in conservinq the energy but also improves the performance and reliability of a wide range of energy systems. Energy storagp. leads to saving of premium fuels and makes the system morA cost effective by reducing the wastage of energy. In most systems there is a mismatch between the energy supply and energy demand. The energy storage can even out this imbalance and thereby help in savings of capital costs. Enerqy storage is all the more important where the enerqy source is intermittent such as Solar Energy. The use of jntermittent energy sources is likely to grow. If more and more solar energy is to be used for domestic and industrial applications then energy storage is very crucial. If no storage is used in solar energy systems then the major part of the energy demand will be met by the back-up or auxiliary energy and therefore the so called annual solar load fract]on will be very low. In case of solar energy, both short term and long term energy storage systems can be used whjch can adjust the phase difference between solar energy supply and energy demand and can match seasonal demands to the solar availability respectively. Thermal energy storage can lead to capital cost savings, fuel savjngs, and fuel substitution in many application areas. Developing an optimum thermal storaqe system is as important an area of research as developinq an alternative source of energy.

Several hundred technically acceptable PCMs were identified in Volume I of this set, and some of their thermodynamic and physical properties were present. Out of these, practical considerations have reduced the list to a few commercial PCMs for solar energy thermal storage heating and cooling applications. In Volume II these PCMs and their technology and discussed.

Several hundred technically acceptable PCMs were identified in Volume I of this set, and some of their thermodynamic and physical properties were present. Out of these, practical considerations have reduced the list to a few commercial PCMs for solar energy thermal storage heating and cooling applications. In Volume II these PCMs and their technology and discussed.

This book covers various aspects of thermal energy storage. It looks at storage methods for thermal energy and reviews the various materials that store thermal energy and goes on to propose advanced materials that store energy better than conventional materials. The book also presents various thermophysical properties of advanced materials and the role of thermal energy storage in different applications such as buildings, solar energy, seawater desalination and cooling devices. The advanced energy storage materials have massive impact on heat transfer as compared to conventional energy storage materials. A concise discussion regarding current status, leading groups, journals and the countries working on advanced energy storage materials has also been provided. This book is useful to researchers, professionals and policymakers alike.