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This study investigates the implementation of passive design strategies to improve the thermal environment in the extremely hot climates of Brazil, Portugal, and Turkey. Given the rising cooling demands due to climate change, optimizing energy efficiency in buildings is essential. Using the Trace 3D Plus v6.00.106 software, typical residential buildings for each country were simulated to assess various passive solutions, such as building orientation, wall and roof modifications, glazing optimization options, window-to-wall ratio (WTWR) reduction, shading, and natural ventilation. The findings highlight that Brazil experienced the higher discomfort temperatures compared to Mediterranean climates, with indoor air temperatures exceeding 28 °C all year round and remaining between 34 °C and 37 °C for nearly 40% of the time. Building orientation had a minimal impact near the equator, while Mediterranean climates benefited from an up to 10% variation in energy demand. Thermal insulation combined with white exterior paint resulted in Şanlıurfa experiencing annual energy savings of up to 26%. Optimal roof solutions yielded a 19% demand reduction in Évora, while WTWR reduction and double-colored glazing achieved up to a 35% reduction in Évora and 19% in other regions. Combined strategies achieved energy demand reductions of 44% for Évora, 40% for Şanlıurfa, and 32% for Teresina. The study emphasizes the need for integrated, climate-specific passive solutions, showing their potential to enhance both energy efficiency and the thermal environment in residential buildings across diverse hot climates.

Climate-change-related events are increasing the costs of power outages, including losses of product, revenue, and productivity. Given the increase in meteorological disasters in recent years related to climate change effects, the number of costly blackouts, from an economic perspective, has increased in a directly proportional manner. As a result, there is increasing interest in the use of alternators to supply dependable, instantaneous, and uninterruptible electricity. Traditional research has focused on the installation of diesel backup systems to ensure power requirements without deeply considering the resilience capabilities of systems, which is the ability of a system to recover or survive adversity, such as a power outage. This research presents a novel approach focusing on the resiliency impact of backup systems’ storage-free dispatchable solutions on buildings and compares the advantages and disadvantages of biomethane microturbines, natural gas engines, and diesel engines backup systems, discussing the revenue resulting from the resilience provided by emergency generators. The results show that, for several diesel fuel and natural gas safety assumptions, natural gas alternators have a lower probability of failure at the time of a blackout than diesel generators, and therefore, resilience increases.

Purpose of this paper is to compare the performance of an alkali metal thermal electric converter (AMTEC) and thermoelectric generator (TEG) as a subsystem for utilizing rejected heat from the molten carbonate fuel cell (MCFC). AMTEC and TEG have various advantages such as; higher power density, no maintenance needed, silent and generally lower cost. Therefore, they have good potential to utilize waste heat. Performance parameters of systems are defined as power output density, exergy destruction rate density, energy and exergy efficiencies. Results show that the system MCFC-AMTEC hybrid system is more advantageous than the MCFC-TEG hybrid system. Some important results are listed follows; maximum power output densities for the MCFC-AMTEC and MCFC-TEG are 2425.833 (W/m2), and 1964.389 (W/m2), respectively, while efficiencies are %, 76.6% and 76.4 %.

Energy Intensive Industries (EII) are high users of energy and some of these facilities are extremely dependent on Natural Gas for processing heat production. In European countries, where Natural Gas is mostly imported from external producers, the increase in international Natural Gas prices is making it difficult for some industries to deliver the required financial results. Therefore, they are facing complex challenges that could cause their delocalization in regions with lower energy costs. European countries lack on-site Natural Gas resources and the plans to reduce greenhouse gas emissions in the industrial sector make it necessary to find an alternative. Many different processes cannot be electrified, and in these cases, synthetic methane is one of the solutions and also represents an opportunity to reduce external energy supply dependency. This study analyzes the current development of power-to-gas technological solutions that could be implemented in large industrial consumers to produce Synthetic Methane using Green Hydrogen as a raw source and using Renewable Energy electricity mainly produced with photovoltaic or wind energy. The study also reviews the triple bottom line impact and the current development status and associated costs for each key component of a power-to-gas plant and the requirements to be fulfilled in the coming years to develop a cost-competitive solution available for commercial use.

This study investigated the performance of a compression ignition engine operating with sunflower ethyl ester. A thermodynamic analysis, including energy and exergy analysis at different engine loads (20%, 40%, 60%, 80%, 100%), was conducted. The study calculated the first and second law efficiency, effective work, heat exergy losses and exergy destruction values at 10 different engine speeds for 5 loads. Maximum work, maximum thermal efficiency, maximum exergy efficiency and maximum volumetric efficiency are determined to be 6.45 kW, 0.26, 0.24 and 0.71 respectively. Finally, optimum operating conditions are discussed and it was determined that the engine should be operated at a lower engine speed for partial loads.

Nano technology is developed in this decade and changes the way of life. Moreover, developing nano technology has effect on the performance of the materials and consequently improves the efficiency and robustness of them. So, nano scale thermal cycles will be probably engaged in the near future. In this paper, a nano scale irreversible Braysson cycle is studied thermodynamically for optimizing the performance of the Braysson cycle. In the aforementioned cycle an ideal Maxwell–Boltzmann gas is used as a working fluid. Furthermore, three different plans are used for optimizing with multi-objectives; though, the outputs of the abovementioned plans are assessed autonomously. Throughout the first plan, with the purpose of maximizing the ecological coefficient of performance and energy efficiency of the system, multi-objective optimization algorithms are used. Furthermore, in the second plan, two objective functions containing the ecological coefficient of performance and the dimensionless Maximum available work are maximized synchronously by utilizing multi-objective optimization approach. Finally, throughout the third plan, three objective functions involving the dimensionless Maximum available work, the ecological coefficient of performance and energy efficiency of the system are maximized synchronously by utilizing multi-objective optimization approach. The multi-objective evolutionary approach based on the non-dominated sorting genetic algorithm approach is used in this research. Making a decision is performed by three different decision makers comprising linear programming approaches for multidimensional analysis of preference and an approach for order of preference by comparison with ideal answer and Bellman–Zadeh. Lastly, analysis of error is employed to determine deviation of the outcomes gained from each plan.

Nowadays with the increasing air traffic, exergy analysis is of great importance in studies aimed efficient use of energy and decreasing environmental impacts caused by aircrafts. In this study, tables for exergy of lift for a hypothetical aircraft have been created with five different engine types. Tables created are for cruise at 8,000ft (2,440m) and climbing at sea level. As a result of this study, it is seen that the engines with higher power and fuel mass flow rate have bigger exergy destruction rates within their components in the meaning of the exergy of lift. The exergy destructions have occurred most greatly at the engines both at the climbing and the cruise. Wing and propeller are the second and third components in this regard, respectively. It is seen that for the components of an aircraft which has a lower aspect ratio there is lesser need for the exergy of lift. During the cruise, the biggest exergy destruction rate in the engine component is occurred approximately as 32 kW at the engine which has the second highest power. As to climb, 473 kW exergy destruction rate which is the biggest value within all engines is occurred at the engine having the biggest power.

In classical thermodynamic, maximum power obtained from system (or minimum power supplied to system) defined as availability (exergy), but availability term is only used for reversible systems. In reality, there is no reversible system, all systems are irreversible, because reversible cycles doesn’t include constrains like time or size and they operates in quasi-equilibrium state. Purpose of this study is to define limits of the all basic thermodynamic cycles and to provide finite-time exergy models for irreversible cycles and to obtain the maximum (or minimum) available power for irreversible (finite-time exergy) cycles. In this study, available power optimization and performance limits were defined all basic irreversible thermodynamic cycles, by using first and second law of thermodynamic. Finally, these results were evaluated in terms of cycles’ first and second law efficiency, COP, power output (or input) and exergy destruction.

Renewable energy is one of the sustainable energy sources, the use of which has increased considerably in recent years. Today, wind energy is an essential renewable energy source that does not have a depletion problem. In this study, electricity generation from wind energy and installed power capacity in Turkey were examined. First, the data set of electrical energy production (GWh) and installed power capacity (MW) between 2010 and 2019 was used. Then, electrical energy generation and installed power capacity were evaluated with trend analysis. Three different models were used in trend analysis, and the results obtained from these models were evaluated with MAPE, MAD, and MSD. Finally, the most suitable models for electric power generation and installed power capacity were determined by evaluating the results.

An irreversible heat pump was investigated via entransy analysis and performance criteria. In the analyses, two different convective heat transfer laws were applied to the considered system: the Newton and Dulong-Petit heat transfer laws. The irreversibilities in the system are the result of a finite heat transfer rate, a heat leak and internal irreversibilities, including friction, turbulence etc. In this study, a thermodynamic analysis was performed in detail, and the numerical solutions were used for the conducted analysis. The maximum entransy dissipation (critical points) ranges from 18436.7 kW K to 18855.3 kW K according to y for Newton's law; however, there is no maximum point for the Dulon-Petit law. It can be concluded from this study that entransy should be used among the basic thermodynamic criteria. [ABSTRACT FROM AUTHOR]

This research presents a novel optimization strategy for concentrating solar power (CSP) plants with thermal energy storage (TES) systems that aims to stabilize and reduce electricity prices in spot markets. In the current international scenario of initiatives with regulatory changes aiming to reduce climate change effects and therefore CO2 emissions, many countries are reducing the fossil fuel share in their respective electrical systems and increasing electrical renewable energy systems. These carbon free generation systems have inherent problems such as their intermittence which, combined with the lack of high-scale energy storage systems, cause a stability risk in electrical grid systems and require conventional fuel systems to match demand and production. In this research, we analyze spot price markets using a marginal price system that relies on natural gas and is quite sensitive to an increase in fuel prices, causing a direct increase in the final energy cost in systems with a high renewable energy share, and we study how optimally sized CSP plants with TES can be used as manageable solar energy systems and contribute to both price and grid stability. For the Spanish market, we analyze the ongoing market situation and generation mix and we present an optimization scheme using the System Advisor Model (SAM) software that aims to maximize energy availability throughout the day and contribute to peak generation. The results show that the optimization strategy increases the profitability of CSP plants but also ensures a contribution to spot price stability and reduction. A sensibility analysis is presented, and a case study is analyzed in southern Spain. The results show the importance of optimized CSP plants in an energy transition and a strategy is proposed that can be extended to other locations worldwide.