Methods, systems, and computer-readable media for use in harvesting heat from subterranean geologic formations

A method comprising:

• a) selecting a subterranean geothermal formation;
• b) selecting an amount and temperature of effluent heat extraction fluid from a geothermal power plant producing power from the subterranean geothermal formation, the effluent heat extraction fluid having an effluent fluid pressure;
• c) selecting an amount and temperature of new heat extraction fluid from a fluid source;
• d) mixing the effluent heat extraction fluid and the new heat extraction fluid to form an initial heat extraction fluid having an initial heat extraction fluid temperature and pressure;
• e) selecting a flowrate of the initial heat extraction fluid;
• f) determining if power produced would meet a power target produced by the geothermal power plant at the temperature, pressure, and flow rate of the initial heat extraction fluid, and
• 1) If the power is less than the power target, increasing the flowrate of the initial heat extraction fluid, and repeating steps (e) and (f);
• 2) If the power is more than the power target, decreasing the flowrate of the initial heat extraction fluid, and repeating steps (e) and (f);
• 3) If the power equals the power target, proceed to step (g);
• g) determining if a producer well pressure would meet a pressure target,
• 1) if the producer well pressure is less than the pressure target, increasing the pressure of the initial heat extraction fluid, and repeating steps (e), (f), and (g);
• 2) If the producer well pressure is more than the pressure target, decreasing the pressure of the initial heat extraction fluid, and repeating steps (e), (f), and (g);
• 3) If the pressure target is met, proceed to step (h);
• h) selecting an injector well geometry and calculating head pressure change, friction pressure change, and enthalpy gain or loss with the subterranean geothermal formation in which the injector well is positioned for the injector well geometry and the initial heat extraction fluid temperature, pressure and flowrate;
• i) flowing the initial heat extraction fluid from the injector well into and through a first heat harvesting stage in the subterranean geothermal formation to form a heated heat extraction fluid;
• j) determining whether another heat extraction stage is required to meet the power target, and if no, proceed to step (k), and if yes, repeat steps (e)-(j);
• k) flowing the heated heat extraction fluid through the producer well to a producer wellhead and then to the power plant.

A computer-readable medium encoded with non-transitory processing instructions for implementing a method, the method comprising:

• a) selecting a subterranean geothermal formation;
• b) selecting an amount and temperature of effluent heat extraction fluid from a geothermal power plant producing power from the subterranean geothermal formation, the effluent heat extraction fluid having an effluent fluid pressure;
• c) selecting an amount and temperature of new heat extraction fluid from a fluid source;
• d) mixing the effluent heat extraction fluid and the new heat extraction fluid to form an initial heat extraction fluid having an initial heat extraction fluid temperature and pressure;
• e) selecting a flowrate of the initial heat extraction fluid;
• f) selecting an injector well geometry and calculating head pressure change, friction pressure change, and enthalpy gain or loss with the subterranean geothermal formation in which the injector well is positioned for the injector well geometry and the initial heat extraction fluid temperature, pressure and flowrate;
• g) determining if power produced would meet a power target produced by the power plant at the temperature, pressure, and flow rate of the initial heat extraction fluid, and
• 1) If the power produced is less than the power target, increasing flowrate of the initial heat extraction fluid, and repeating steps (e), (f), and (g);
• 2) If the power produced is more than the power target, decreasing flowrate of the initial heat extraction fluid, and repeating steps (e), (f), and (g);
• 3) If the power produced equals the power target, proceed to step (h);
• h) determining if a producer well pressure would meet a producer well pressure target,
• 1) If the producer well pressure is less than the pressure target, increasing the initial heat extraction fluid pressure, and repeating steps (e)-(h);
• 2) If the producer well pressure is more than the pressure target, decreasing the initial heat extraction fluid pressure, and repeating steps (e)-(h);
• 3) If the producer well pressure equals the pressure target, proceed to step (i);
• i) flowing the initial heat extraction fluid from the injector well into and through a first heat extraction stage in the subterranean geothermal formation to form a heated heat extraction fluid;
• j) determining whether a second heat extraction stage is required to meet the power target, and if no, proceed to step (k), and if yes, repeat steps (e)-(i);
• k) flowing the heated heat harvesting fluid through the producer well to a producer wellhead and then to the power plant.

A computer-readable medium encoded with non-transitory processing instructions for implementing a method, the method comprising:

• a) selecting a subterranean geothermal formation;
• b) selecting an amount and temperature of effluent heat extraction fluid from a geothermal power plant producing power from the subterranean geothermal formation, the effluent heat extraction fluid having an effluent fluid pressure;
• c) selecting an amount and temperature of new heat extraction fluid from a fluid source;
• d) mixing the effluent heat extraction fluid and the new heat extraction fluid to form an initial heat extraction fluid having an initial heat extraction fluid temperature and pressure;
• e) selecting a flowrate of the initial heat extraction fluid;
• f) determining if power produced would meet a power target produced by the geothermal power plant at the temperature, pressure, and flow rate of the initial heat extraction fluid, and
• 1) If the power is less than the power target, increasing the flowrate of the initial heat extraction fluid, and repeating steps (e) and (f);
• 2) If the power is more than the power target, decreasing the flowrate of the initial heat extraction fluid, and repeating steps (e) and (f);
• 3) If the power equals the power target, proceed to step (g);
• g) determining if a producer well pressure would meet a pressure target,
• 1) If the producer well pressure is less than the pressure target, increasing the pressure of the initial heat extraction fluid, and repeating steps (e), (f), and (g);
• 2) If the producer well pressure is more than the pressure target, decreasing the pressure of the initial heat extraction fluid, and repeating steps (e), (f), and (g);
• 3) If the pressure target is met, proceed to step (h);
• h) selecting an injector well geometry and calculating head pressure change, friction pressure change, and enthalpy gain or loss with the subterranean geothermal formation in which the injector well is positioned for the injector well geometry and the initial heat extraction fluid temperature, pressure and flowrate;
• i) flowing the initial heat extraction fluid from the injector well into and through a first heat harvesting stage in the subterranean geothermal formation to form a heated heat extraction fluid;
• j) determining whether another heat extraction stage is required to meet the power target, and if no, proceed to step (k), and if yes, repeat steps (e)-(j);
• k) flowing the heated heat extraction fluid through the producer well to a producer wellhead and then to the power plant.