Cascaded condenser for multi-unit geothermal orc

Abstract

A pair of organic rankine cycle systems are connected in series with the geothermal fluid passing first through an evaporator of the first system and then through an evaporator of the second system before returning to a sink. Similarly, the cooling tower is arranged to provide cooling water to pass first through the condenser in one system and then through the condenser of the other system, to reduce the total flow required and the size of associated cooling hardware.

1 . A cascaded arrangement of a pair of organic rankine cycle systems with each having in serial working fluid flow relationship a turbine, a condenser, a pump and an evaporator, comprising:
 a source of high temperature fluid adapted to flow serially through a first evaporator to heat the working fluid of a first system and then through a second evaporator to heat the working fluid of a second system; and   a source of cooling fluid adapted to flow serially through the first condenser to cool the working fluid of a first system and then through a second condenser to cool the working fluid of a second system.   
     
     
         2 . A cascaded arrangement as set forth in  claim 1  wherein said source of higher temperature fluid is a geothermal source. 
     
     
         3 . A cascaded arrangement as set forth in  claim 1  and including a single pump for pumping said cooling fluid in a closed circuit. 
     
     
         4 . A cascaded arrangement as set forth in  claim 1  and including a single cooling tower for providing cooling fluid to said first condenser and receiving cooling fluid from said second condenser. 
     
     
         5 . A cascade arrangement as set forth in  claim 1  and including a single cooling fluid stream wherein the working fluid passes through the condensers in counterflow relationship with the working fluid flow.