The evaluation of ecosystem health is a fundamental process for conducting effective ecosystem management. Ecological exergy is used primarily to summarize the complex dynamics of lotic ecosystems. In this study, we characterized the functional aspects of lotic ecosystems based on the exergy and specific exergy from headwaters to downstream regions in the river’s dimensions (i.e., river width a...

Photovoltaic power generation is a growing renewable primary energy source, expected to assume a major role as we strive toward fossil fuel free energy production. However, the photovoltaic efficiencies limit the conversion of solar radiation into useful power output. Hybrid systems extend the functionality of concentrating photovoltaics (CPV) from simply generating electricity, to providing si...

Performance evaluation of a thermodynamic system under off-design conditions is very important for reliable and cost-effective operation. In this study, an off-design model of an organic Rankine cycle driven by solar energy is established with compound parabolic collector (CPC) to collect the solar radiation and thermal storage unit to achieve the continuous operation of the overall system. The...

This study analyzes the thermal performance of solar thermal energy using double-pass absorber plate in Sanandaj, Iran. To this end, a mathematical model was encoded according to the energy and exergy balance equations and solved by MATLAB software. Given the environmental conditions and radiation intensity of a winter day in Sanandaj, the effects of external parameters such as radiation intens...

This paper presents a detailed exergetic analysis of a novel high-temperature Solar Assisted Combined Cycle (SACC) power plant. The system includes a solar field consisting of innovative high-temperature flat plate evacuated solar thermal collectors, a double stage LiBr-H2O absorption chiller, pumps, heat exchangers, storage tanks, mixers, diverters, controllers and a simple single-pressure Com...

Nowadays, energy plays an important role in the economic and community development of country. Consequently, performance analysis of energy systems is one of the effective methods being used to prevent waste of energy resources. Among the different power generation technologies, steam power plants make a significant contribution to power generation in Iran, with a share of 47 % of electricity g...

Nowadays, energy plays an important role in the economic and community development of country. Consequently, performance analysis of energy systems is one of the effective methods being used to prevent waste of energy resources. Among the different power generation technologies, steam power plants make a significant contribution to power generation in Iran, with a share of 47 % of electrici...

The objectives of this study are to (a) evaluate the exergy and energy demand for constructing a hydrofractured shale gas well and determine its typical exergy and energy returns on investment (ExROI and EROI), and (b) compute the gas flow and intrinsic exergy analysis in the shale gas matrix and created fractures. An exergy system analysis of construction of a typical U.S. shale gas well, whic...

in this paper, a hybrid solid oxide fuel cell (sofc) and micro gas turbine (mgt) power system is parametrically studied to evaluate the effect of different operating conditions. the sofc/mgt power system includes sofc reactor, combustion chamber, compressor and turbine units, and two heat exchangers. the effects of fuel utilization, temperature, and pressure are assessed on performance of the h...