| Abstract |
A new type of power system utilizing a variable composition, multi-component working fluid power cycle (conventionally referred to as a Kalina Cycle) has been developed by Kalex LLC. This system is designed mainly for utilizing heat from liquid dominated geothermal sources. The composition of the system's working fluid changes in different parts of the system, which allows the system to achieve high thermodynamical (exegetical) efficiencies (the thermodynamical efficiency is the ratio of the actual thermal efficiency of the system to the maximum theoretical efficiency according to the Second Law of Thermodynamics). The composition of the working fluid is also variable based on the ambient temperature, which allows for the maintenance if a high thermodynamical efficiency with changing weather conditions. Although a water-ammonia mixture is the intended mixture for the system's working fluid, the system can also work with a mixture of freons and/or hydrocarbons. This system works in an optimum manner with an initial temperature of geofluid from 380 F to 250 F (180 C to 120 C). The thermodynamical efficiency of the system is always within the range from 50% to 60%. Thus, at any boundary conditions within the operational range, the efficiency is from 20% to 40% higher than the efficiency of systems based on the organic Rankine cycles which are conventionally used for the utilization of these types of geothermal sources. |