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This paper presents a thermoeconomic analysis and assessment of a municipal solid waste power plant system in Gaziantep. The operation of an existing municipal solid waste power plant is described in detail and a thermoeconomical methodology based on exergoeconomic relations and specific exergy costing (SPECO) method is provided to allocate cost flows through subcomponents of the plant. SPECO method is based on a step by step procedure which begins from identification of energy and exergy values of all states defined in the present system through fuel (F) and product (P) approach and ends at the point of establishing related exergy based cost balance equations together with auxiliary equations. The actual exergy efficiency of the solid waste power plant is determined to be 47.84% which shows that 52.16% of the total exergy input to the plant is destroyed. The net electrical power output of the Gaziantep municipal solid waste power plant is 5.655 MW. The total cost rate of the power plant is evaluated as 18.44$/h as a result of thermoeconomic analyses.

An experimental investigation is performed for an organic Rankine cycle system with different electrical resistive loads. The test rig is set up with a small scroll expander-generator unit, a boiler and a magnetically coupled pump. R134a is used as the working fluid in the system. The experimental results reveal that the resistive load coupled to the scroll expander-generator unit affects the expander performance and power output characteristics. It is found that an optimum pressure ratio exists for the maximum power output. The optimal pressure ratio of the expander decreases markedly as the resistive load gets higher. The optimum pressure ratio of the scroll expander is 3.6 at a rotation speed of 3450 r/min for a resistive load of 18.6 ?. The maximum electrical power output is 564.5 W and corresponding isentropic and volumetric efficiencies are 78% and 83% respectively.

Commonly, the thermal behavior of solar cell modules is calculated with analytical approaches using non wavelength-dependent optical data. Here, we employ ray tracing of entire solar modules at wavelengths of 300-2500 nm to calculate heat sources. Subsequently, finite element method (FEM) simulations are used to solve the semiconductor equations coupled with the thermal conduction, thermal convection, and thermal radiation equations. The implemented model is validated with measurements from an outdoor test over the period of an entire year. Our ray tracing analysis of different solar modules under the AM.15G spectrum shows that, for a standard module about 18.9% of the sun's intensity becomes parasitically absorbed. A loss analysis shows that the biggest parasitic heat source is the cell's full-area rear side metallization. We hence propose the use of a SiN x layer as rear side mirror to reduce the parasitic absorption to 11.7%. This change can lead to a 3.2 °C lower module operating temperature, which results in an about 5 W higher electrical power output when considering a typical 260 W module.