Lightweight concrete from a perspective of sustainable reuse of waste byproducts

This paper introduces the recent developments in Renewable Energy Systems for building heating, cooling and electricity production with thermal energy storage. Due to the needed Clean Energy Transition in the many countries and regions and the goal of closing Net Zero Energy Buildings, it is crucial to provide efficient Renewable Energy Based heating/cooling systems for buildings. The buildings contribute about 40% of total energy consumption, with significant potential for primary energy savings. The application of various Renewable Energy based systems is discussed including: the presentation of Hybrid Renewable Energy bases systems, methodology for their design and methods for the optimisation of Buildings RES. At present, mostly the systems based on heat pumps and photovoltaics are applied in buildings. However, the sources of those energy systems are unstable, and they are influenced by the climate environment. It makes it necessary to combine thermal and electrical energy storage, to achieve high efficiency. The recently developing electrical energy and chemical storage are Battery Energy Storage Systems and Hydrogen Energy Systems, through it is urgently necessary to overcome the difficulties of high cost, relatively low efficiency and demanding storage environment and so on. For the thermal energy storage, Phase Change Materials (PCMs) show great potential for application – with their use the thermal energy can be accumulated at the time of low energy demand or availability and recovered during a high consumption period. This review also presents the recent developments in PCMs for their application in buildings, both for heating and cooling. Finally, it sorts out some challenging issues of the RES today and guides future development. 

Renewable energy systems for building heating, cooling and electricity production with thermal energy storage

Encapsulation of inorganic phase change thermal storage materials and its effect on thermophysical properties: A review

World over, research inventions have spiraled around sustainable energy solutions including the advent of phase change material based thermal energy storage systems. The application of these systems in thermo-regulating systems such as refrigeration, air conditioning, personal thermal comfort, building and construction, has been widely accepted. Most current focuses are on the topical reads of the enhancements of the phase change materials for optimized performance in thermal energy storage mechanisms. Recent publications have persistently suggested the use of nanoparticles to solve the phase change materials' low thermal-conductivity, supercooling, leakage, phase segregation and inflammability problems amongst others. This has not only shown promise of improved heat transfer and phase transition performance but also, reduced charging time and phase transition temperatures amongst many other benefits with limited distortion of other material properties. However, the process of preparing the nano-enhanced phase change material s is highly technical, requiring special equipment and precise procedures. Many studies indicated significant improvement in the phase change materials' thermal and mechanical properties when the nanomaterials were added, but some works also highlighted that the enhancement also came with a diminishing effect on the latent heat storage capacity of the phase change material. It is against these premises, that this current study does not only aim to give a detailed review of present-day advancements of nano-enhanced - phase change material but, also seeks to show how a homogenous mixture of nano-enhanced phase change material can be prepared and present the impacts of such material. 

An overview of the preparation and characteristics of phase change materials with nanomaterials

Glass fiber reinforced gypsum composites with microencapsulated PCM as novel building thermal energy storage material

Inorganic phase change materials in thermal energy storage: A review on perspectives and technological advances in building applications

The use of marginal-quality waters, not limited to brackish/saline and treated sewage effluent (TSE), is called reclaimed water. Reclaimed water is a sustainable source in the future for use in agriculture, essentially required to offset the food demand of a rapidly growing population. Moreover, the sustainable recovery of reclaimed water is essential for humanity to satisfy extreme sanitation and water-supply demands. To increase access to water supply, alternate water resources’ use, existing water resources’ degradation, and improved water-use efficiency are imperative. There is a high potential to address these factors by using reclaimed water as an alternative source. The reclaimed water treated at a tertiary level has the potential for use in crop production, especially for forage crops, irrigating urban landscapes, recreational and environmental activities, industry, and aquifer recharge to increase strategic water reserves in water-scarce countries. This way, we can save precious freshwater that can be utilized for other purposes. Eminently, freshwater applications for industrial and agronomic sectors account for 20% and 67%, respectively, depleting freshwater resources. The use of reclaimed water in agriculture can significantly reduce pressure on freshwater. However, if the quality of reclaimed water does not comply with international standards, it may cause serious health risks (diseases) and soil pollution (heavy metals).

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Towards Sustainable Application of Wastewater in Agriculture: A Review on Reusability and Risk Assessment

Limited postharvest life of tomato fruit is due to its highly perishable nature. Hypobaric pressure is a new emerging hurdle technology usually used up to a pressure of 100 kPa for the preservation of fruits and vegetables. In this study, an integrated approach of hypobaric pressures (40 kPa and 50 kPa) and sponge-dipping of potassium permanganate (KMnO4) was designed for the postharvest life extension of tomato fruits. Fruits were treated with either 400 ppm of KMnO4, or 40 or 50 kPa hypobaric pressures, or their combination. Fruits without any treatment was considered as a control treatment. All groups were packaged in polypropylene trays as ready to retail and stored at room temperature at 25 ± 1 ℃ for 21 days. Basic quality parameters such as pH, total soluble solid, percent weight loss, percent spoilage, firmness, ethylene production rate, and color were evaluated at 3-day intervals. Results showed the application of hypobaric pressures and KMnO4, either alone or in combination, provided a synergistic effect in maintaining the quality compared to the control treatment during the 21 days of storage. The highest decay was found in the control compared to the combined treatments of KMnO4 + 40 kPa and KMnO4 + 50 kPa. Similarly, a decrease in firmness and color values was highest in the control treatment followed by the KMnO4 and 50 kPa hypobaric pressure compared to the combined treatment of KMnO4 + 50 kPa. In the same way, a high ethylene production rate was observed in the control, while the lowest ethylene production rate was found in KMnO4 + 50 kpa. Sensory evaluation indicated a highest score of 9 on the 9-point hedonic scale of tomato fruits. Among all groups, the combined application of 50 kPa hypobaric pressure + 400 ppm KMnO4 retained the best overall quality attributes compared to all other treatments throughout the experiment; therefore, this treatment could be applied at a commercial level for tomato fruits.

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Imran Khan

Papers

Inorganic phase change materials in thermal energy storage: A review on perspectives and technological advances in building applications

Towards Sustainable Application of Wastewater in Agriculture: A Review on Reusability and Risk Assessment

An Integrated Approach of Hypobaric Pressures and Potassium Permanganate to Maintain Quality and Biochemical Changes in Tomato Fruits