Solar Rankine Cycle System Using Scroll Expander

Abstract

A unique solar thermal electric system is proposed and tested in the present study. In this system, an organic working fluid, which is suitable for a temperature range appropriate for solar energy, is adopted. We call this system as "solar organic Rankine cycle system" (SORCS). In order to improve the thermal efficiency by using solar energy, a displacement-type scroll expander and compound parabolic concentrator (CPC) solar collector are used. This system consists of very simple components that are similar to the ones used in an air conditioner and is very cost effective. The present paper reports on the experimental results of the scroll expander unit and the practical operation of the proposed SORCS under actual solar radiation input. The total thermal efficiency of the present SORCS attains 7% (42% when cooling water is used for the cogeneration system).

Performance of Organic Rankine Cycle in Different Refrigerants for Low Temperature Geothermal using Delphi Program

“…It is found that the presence of hydrogen bond in certain molecules such as water, ammonia and ethanol may result in lager vaporizing enthalpy, and is regarded as inappropriate for ORC system. Experimental study was also proposed to improve the thermal efficiency by using solar energy [7]. A displacementtype scroll expander and compound parabolic concentrator solar collector are used.…”

A thermodynamic criterion for selection of working fluid for subcritical and supercritical domestic micro CHP

“…Nevertheless, there ought to be included transmission losses, which permit to say that the micro CHP units, planned to be developed in the near future, are quite promising technologies. Literature sees several studies where different micro-ORC systems designed for heat production and electricity generation were studied, see for example Nguyen et al [1], Saitoh et al [2], Lemort et al [3]. There are still issues requiring particular attention in appropriate implementation of that technology in practice, namely the expansion device, which in the above cases was a modified scroll compressor to the expansion mode.…”

Thermodynamic Analysis of Expansion Profile for Displacement-type Expander in Low-temperature Rankine Cycle

“…To design a displacement-type expander with a variable expansion mechanism, the required optimal expansion profile of the working fluid must first be known; the expansion profile should fit the cell volume profile from the inlet (intake port) to the outlet (discharge port) of the displacement-type expander. Screw and scroll expanders [8] [12] are two types of displacement-type expanders that are often employed in low-temperature Rankine cycle systems. In this study, we first analyzed the expansion profiles of three typical working fluids: HFC245fa (dry fluid), ammonia (wet fluid), and supercritical CO 2 .…”

“…The evaporator and condenser are heat exchangers in the cycle that absorb and release heat. [8] . The cycle starts by the pump pushing the working fluid to the evaporator.…”