Exergy analysis of solar Rankine power cycles used for cooling

Conference · Sat Jan 01 04:00:00 EST 1983

OSTI ID:6370837

Brady, III, W J

Second-law (exergy) analysis was performed on two types of solar-cooling systems which are based on a vapor-compression cycle driven by a Rankine cycle: those energized by the sun at one temperature and using organic fluids in the power cycle, and a hybrid cycle which is energized by a solar source at a low temperature and by a fossil source at a higher temperature and using steam as the fluid. Some of the major conclusions are: (1) A better thermodynamic match is obtained between the energy sources and sinks in the hybrid cycle, which results in a doubling of the cycle's efficiency as compared to the single-temperature organic-fluid cycle. Nevertheless, there still exists a large difference between the temperatures of combustion (approx. 1500/sup 0/C) and superheated steam (approx. 600/sup 0/C), and thus the superheater's effectiveness is relatively low. This points to several methods of improvement, including improved heat-transfer design, and utilization of the stack gases. (2) Applying superheat by solar concentrators instead of combustion improves cycle effectiveness by about 40%, and (3) the heat exchangers to recover heat from the steam after it has been exhausted from the turbine have an important influence on energy and exergy recovery but need to be carefully optimized.

• Research Organization: Pennsylvania Univ., Philadelphia (USA). Dept. of Mechanical Engineering and Applied Mechanics
• DOE Contract Number: AC03-78ET20110
• OSTI ID: 6370837
• Report Number(s): SAN-20110-9; CONF-830622-17; ON: DE83011834
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140901* -- Solar Thermal Utilization-- Space Heating & Cooling
CONCENTRATING COLLECTORS
EFFICIENCY
ENERGY
ENERGY RECOVERY
EQUIPMENT
EXERGY
HEAT RECOVERY
HYBRID SYSTEMS
PARABOLIC COLLECTORS
PARABOLIC DISH COLLECTORS
RANKINE CYCLE
RECOVERY
SOLAR COLLECTORS
SOLAR COOLING SYSTEMS
SOLAR EQUIPMENT
THERMAL ANALYSIS
THERMODYNAMIC CYCLES
VAPOR COMPRESSION REFRIGERATION CYCLE