Improving Closed-Loop Geothermal Predictions with CMG STARS

Closed-loop geothermal systems offer a pathway to unlock heat from non-hydrothermal (“dry”) formations, but their feasibility depends heavily on how heat transfer is modeled.

A comprehensive study conducted by JOGMEC (Japan Oil, Gas and Metals Corporation) evaluated multiple closed-loop configurations using four simulation approaches:

• CMG STARS 
• COMSOL Multiphysics 
• GEOSIM (CRIEPI geothermal simulator) 
• Analytical models

Outcome: CMG STARS predicted production temperatures up to 20-40°C higher than other tools by capturing thermally-driven natural convection in the surrounding formation. This highlighted how modeling assumptions can significantly influence performance predictions across closed-loop geothermal systems.