Enhanced carbon dioxide-based geothermal energy generation systems and methods

Abstract

A system comprises an injection well for accessing reservoir at a first temperature; a production well in fluid communication with the reservoir; a working-fluid supply system providing a non-water based working fluid to the injection well at a second temperature lower than the first temperature, wherein exposure of the working fluid to the first temperature heats the working fluid to a third temperature and at least a portion of the working fluid at the third temperature is produced as a production fluid; and an energy recovery system that converts energy contained in the production fluid to electricity or heat, wherein the energy recovery system includes a waste heat recovery apparatus that recovers waste heat and uses it to heat the production fluid to a fourth temperature that is higher than the third temperature, wherein the waste heat is recovered from equipment of or a process stream.

What is claimed is: 
     
         1 . A system comprising:
 one or more injection wells for accessing one or more underground reservoirs, the one or more reservoirs being at one or more first temperatures and containing at least one native fluid, the native fluid including a solution comprising methane, each of the one or more injection wells having an injection well reservoir opening in fluid communication with at least one of the one or more reservoirs;   one or more production wells, each having a production well reservoir opening in fluid communication with at least one of the one or more reservoirs;   a working-fluid supply system for providing a non-water based working fluid to the one or more injection wells at a second temperature lower than the first temperatures,   wherein exposure of the non-water based working fluid to the native fluid causes at least a portion of the methane to come out of solution with the native fluid to form a production fluid of at least a portion of the non-water based working fluid and the portion of the methane,   wherein exposure of the mixture to the first temperatures heats the production fluid to a third temperature that is higher than the second temperature, wherein the production fluid is capable of entering one or more of the production well reservoir openings; and   an energy recovery apparatus in fluid communication with the one or more productions wells, wherein energy contained in the production fluid can be converted to electricity, heat, or a combination thereof, in the energy recovery apparatus.