Organic Rankine cycle coupled to a solar pond by direct-contact heat exchange: selection of a working fluid
Heat from a solar pond may be used to drive an organic Rankine cycle and produce electricity. Due to the inherent low efficiency of low-temperature cycles, large amounts of heat must be transferred, and heat exchangers may account for up to 50% of the plant cost. Use of a direct-contact boiler, in which the organic fluid is bubbled through a stream of pond brine, may reduce the plant cost by about 25%. The choice of a working fluid affects plant efficiency, turbine cost, and the loss rate of the organic fluid. Low-vapor-pressure fluids maximize cycle efficiency by minimizing pumping requirements, but require a larger turbine. Because efficiency affects the size and cost of the entire plant, low-pressure fluids are preferred. Both the saturated and halogenated hydrocarbons were evaluated for use as working fluids. Pentane was the working fluid best suited to this application, because it showed high efficiency, low solubility in the pond, and a reasonable turbine cost.
- Research Organization:
- Solar Energy Research Inst., Golden, CO (USA)
- DOE Contract Number:
- AC02-77CH00178
- OSTI ID:
- 6168619
- Report Number(s):
- SERI/TR-631-1122; ON: DE81028400
- Country of Publication:
- United States
- Language:
- English
Similar Records
Selection of working fluid for an organic Rankine cycle coupled to a salt-gradient solar pond by direct-contact heat exchange
Thermal analysis of a solar pond power plant operated with a direct contact boiler
Related Subjects
SOLAR PONDS
SOLAR THERMAL POWER PLANTS
DIRECT CONTACT HEAT EXCHANGERS
WORKING FLUIDS
DESIGN
ECONOMICS
EFFICIENCY
HYDROCARBONS
PENTANE
POWER GENERATION
RANKINE CYCLE
SALINITY GRADIENTS
TURBINES
ALKANES
EQUIPMENT
FLUIDS
HEAT EXCHANGERS
MACHINERY
ORGANIC COMPOUNDS
PONDS
POWER PLANTS
SOLAR COLLECTORS
SOLAR EQUIPMENT
SOLAR POWER PLANTS
THERMAL POWER PLANTS
THERMODYNAMIC CYCLES
TURBOMACHINERY
140700* - Solar Thermal Power Systems
141000 - Solar Collectors & Concentrators