A positive temperature coefficient is the term which has been used to indicate that an increase in solubility occurs as the temperature is raised, whereas a negative coefficient indicates a decrease in solubility with rise in temperature.

Effect of Temperature

Building energy-consumption status worldwide and the state-of-the-art technologies for zero-energy buildings during the past decade

Aerogel is a kind of synthetic porous material, in which the liquid component of the gel is replaced with a gas. Aerogel has specific acoustic properties and remarkably lower thermal conductivity (≈0.013 W/m K) than the other commercial insulating materials. It also has superior physical and chemical characteristics like the translucent structure. Therefore, it is considered as one of the most promising thermal insulating materials for building applications. Besides its applications in residential and industrial buildings, aerogel has a great deal of application areas such as spacecrafts, skyscrapers, automobiles, electronic devices, clothing etc. Although current cost of aerogel still remains higher compared to the conventional insulation materials, intensive efforts are made to reduce its manufacturing cost and hence enable it to become widespread all over the world. In this study, a comprehensive review on aerogel and its utilization in buildings are presented. Thermal insulation materials based on aerogel are illustrated with various applications. Economic analysis and future potential of aerogel are also considered in the study.

Toward aerogel based thermal superinsulation in buildings: A comprehensive review

In recent years, energy conservation and environmental protection have become most important issues for humanity. Phase change materials (PCMs) for thermal energy storage can solve the issues of energy and environment to a certain extent, as PCMs can increase the efficiency and sustainability of energy. PCMs possess large latent heat, and they store and release energy at a constant temperature during the phase change process. Thereby PCMs have gained a wide range of applications in various fields, such as buildings, solar energy systems, power systems and military industry. However, low thermal conductivity of PCMs leads to low heat transfer rate, thus, numerous studies have been carried out to improve thermal conductivity of PCMs. The main purpose of this paper is to review the methods for enhancing thermal conductivity of PCMs, which include adding additives with high thermal conductivity and encapsulating phase change materials. It is found that addition of thermal conductivity enhancement fillers is a more effective method to improve thermal conductivity of PCMs, where carbon-based material additives possess a more promising application prospect. Finally, the applications of PCMs in solar energy system, buildings, cooling system, textiles and heat recovery system are also analyzed.

Review on thermal conductivity enhancement, thermal properties and applications of phase change materials in thermal energy storage

Cell modelling and model parameters estimation techniques for photovoltaic simulator application: A review

A comprehensive review on solar cookers

In this study, a comprehensive review focusing on key strategies of energy saving and climate control technologies for greenhouses is presented. Following the brief and concise assessment of existing greenhouse systems in terms of their role in total energy consumption; cost-effective, energy-efficient and environmentally friendly technologies are analyzed in detail for potential utilization in greenhouses for notable reductions in energy consumption and emission levels. The technologies considered within the scope of this research are mainly renewable and sustainable based solutions such as photovoltaic (PV) modules, solar thermal (T) collectors, hybrid PV/T collectors and systems, phase change material (PCM) and underground based heat storage techniques, energy-efficient heat pumps, alternative facade materials for better thermal insulation and power generation (heat insulation solar glass, PV glazing, aerogel and vacuum insulation panel, polycarbonate sandwich panels), innovative ventilation technologies using pre-heating and cooling (high performance windcatchers) and efficient lighting systems. The findings from the research clearly reveal that up to 80% energy saving can be achieved through appropriate retrofit of conventional greenhouses with a payback period of 4–8 years depending on climatic conditions and crop type.

Renewable and sustainable energy saving strategies for greenhouse systems: A comprehensive review

An experimental analysis of illumination intensity and temperature dependency of photovoltaic cell parameters

Building sector accounts for more than 60% of total energy consumption in the world while the share of domestic buildings is about 20–40%. The energy consumed is mostly utilised for heating, cooling and ventilation purposes. The energy efficiency of buildings is of prime concern for an occupant who wants to make energy saving especially in HVAC sector. In this instance, it is essential to focus on energy efficient technologies and solutions not only in new buildings but also in existing buildings. One of the energy efficient technologies is evaporative cooling system which is very suitable especially for hot and dry climatic conditions. In this paper, a thorough review of evaporative cooling technologies and their building applications is presented. Evaporative cooling is a novel technology that supplies cool air to the occupants as well as providing a promising way to reduce carbon emissions and energy consumption. Evaporative cooling is a concept that is defined as making air cool via increasing its water vapour content. In other words, air becomes cooler while its humidity level increases. The results show that the evaporative cooling systems have a great potential to save energy in hot and arid climatic zones. It also seems that this novel solution is a very cost effective way compared to the alternative air-conditioning applications.

Pinar Mert Cuce

Papers

Toward aerogel based thermal superinsulation in buildings: A comprehensive review

A comprehensive review on solar cookers

Renewable and sustainable energy saving strategies for greenhouse systems: A comprehensive review

An experimental analysis of illumination intensity and temperature dependency of photovoltaic cell parameters

A state of the art review of evaporative cooling systems for building applications