MIXTURES OF CO2-SF6 AS WORKING FLUIDS FOR GEOTHERMAL PLANTS

Conference · Sat Jan 01 04:00:00 EST 2011

OSTI ID:1033529

Sabau, Adrian S ^[1]; Yin, Hebi ^[1]; McFarlane, Joanna ^[1]; Qualls, A L ^[1]; Conklin, Jim ^[1]; Pawel, Steven J ^[1]

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1. ORNL

In this paper, mixtures of CO2 and SF6 were evaluated as working fluids for geothermal plants based on property measurements, molecular dynamics modeling, thermodynamic cycle analysis, and materials compatibility assessment. The CO2 - SF6 was evaluated for a reservoir temperature of 160 oC. Increasing the efficiency for these low reservoir sources will increase the options available for geothermal energy utilization in more sites across the country. The properties for the mixtures were obtained either from thermodynamic property measurements and molecular dynamics simulations. Optimum compositions of the CO2 - SF6 were identified for a well reservoir temperature and a given water-cooling condition. Concerning the global warming potential, it was estimated that the equivalent CO2 emissions per 1kWh for a Rankine cycle operating with 100% SF6 would be approximately of 7.6% than those for a coal-fired power plant.

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: EE USDOE - Office of Energy Efficiency and Renewable Energy (EE)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1033529
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
COMPATIBILITY
EFFICIENCY
GEOTHERMAL ENERGY
GREENHOUSE EFFECT
MECHANICAL ENGINEERING
MIXTURES
MOLECULAR DYNAMICS METHOD
POWER PLANTS
RANKINE CYCLE
RESERVOIR TEMPERATURE
SIMULATION
THERMODYNAMIC CYCLES
THERMODYNAMICS
WORKING FLUIDS