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In order to attain an efficient path into the enhancement of the sustainable conservation and management of energy resources in the buildings and residential sections, efforts by all relevant institutions in the area of energy are essential and primitive. Hence, the development of the energy supply model in the building and the provision of fundamental solutions in this area is rudimentary. The key to any program related to this matter is to boost and extend energy efficiency and energy resource management. According to the global statistics and processed data, the residential sector accounts for 34 percent of the total energy consumption in Iran, which is the highest energy consumption compared to all existing sectors; therefore, immeasurable research has been done on optimizing energy usage in the building sector. One of the most efficient energy optimization methods can be achieved by using energy storage materials in the outer walls of the buildings. In this project, a research‐based residential building is considered as a case to investigate for energy optimization. In the first stage, the building is simulated and the energy consumption of the building is measured. Afterward, with actual measurements, real consumption is approximated and compared with the results of the software. After verifying the software data, the insulation is simulated in the software and the outcomes of using this insulator are investigated to reduce energy consumption. Energy storage materials are considered as a type of phase‐change material. These materials have the same characteristics which is having a different melting point and, by capturing and losing heat at design temperatures, they can help maintain energy inside the building that is how they can be considered as an insulator. Within the appropriate software which is Design‐Builder, miscellaneous types of these materials are available with various features. The final results point out that the use of this material saves up to 30% of the heating energy and about 8% in the cooling load of the building. [ABSTRACT FROM AUTHOR]

Properties of desirable weight, latent heat capacity, and energy storage capability of phase change materials (PCMs) have led to extensive use of these materials in the building industry as productive thermal mass. This study investigated the feasibility of the utilization of PCMs through numerical simulations in residential buildings located in different Iranian climates in Tehran, Tabriz, Yazd, and Bandar Abbas. In so doing, the optimal PCM for each city was selected based on its impact on annual energy consumption, and then its effects on the indoor temperature and thermal load of the model in the hottest and coldest months of the year were examined. The results showed that the use of PCMs does not lead to significant energy conservation in the hot and humid climate of Bandar Abbas compared with other climates. In the second part of the study, the economic feasibility of PCMs and the payback period of such investment were investigated based on the current local electricity and natural gas prices. It was found that although the use of PCMs leads to significant energy conservation in most of these climates, with the current prices of energy and PCMs in Iran, the use of these materials will not be cost-effective, as the return periods for such investment in Tehran, Tabriz, Yazd, and Bandar Abbas will be 42, 179, 102, and 114 years, respectively. [ABSTRACT FROM AUTHOR]

One of the most common issues associated with wind energy penetration as a viable resource is high instability under diverse amplitudes and frequencies. Compressed air storage systems (CAES) and thermal energy storages (TES) not only are promising alternative solution for renewable resources generally, but they are also used with the aim of peak shaving to provide cleaner and affordable power. Due to high storage density with low temperature gradient between storing and retrieving in comparison with sensible heat storage, phase change material (PCM) is selected considering their thermophysical properties. This work, presents a recovery approach by using PCM during 12 h' compression periods to retrieve it in 12 h' expansion as a case study in November for Baladeh (a city in north of Iran). It is worthy to mention that, in order to use PCM in multiple mentioned stages, auxiliary heaters facilitate system to provide constant heat load in each used stage. This concludes system to be more efficient, sustainable and can reduce irreversibilities. Temperature of PCMs and amount of heat stored and released versus time are modeled. A good agreement between PCM model and reported results of related articles was seen. Following to the energy and exergy balances calculation, round-trip efficiency (RTE) and total exergy efficiency of system, reach 70.83%, 80.71%. Exergy analysis showed that near 60% exergy destruction occurred in PCMs with major contribution of second ones in both charge and discharge times. Sensitivity analysis is also investigated assuming the effect of number of wind turbines which shows a reduction in RTE, steeper slope in increasing TES volume for PCM3 and amount of heat stored, by increasing them. Image 10372 • A hybrid renewable energy storage system using phase change materials is investigated. • Compressed air storage and thermal energy storage methods are integrated. • RTE and total exergy efficiency of the system, reach 70.83%, 80.71%. • A city in north of Iran is considered for design of wind farm integrated to the energy system. [ABSTRACT FROM AUTHOR]