Well spacing of the doublet at the Huangtsuishan geothermal site, Taiwan.

• The larger well spacing of the doublet wells effectively delays thermal breakthrough. • A regression formula for required distance of doublets is provided for the study Site. • A distance of 300 m avoids thermal breaks for the hypothetical exploitation scenarios. The issue of thermal breakthrough is often encountered in the extraction of geothermal fluids with reinjection. This study analyzes the minimum safe distance between doublet wells that will maintain thermal productivity under various conditions at the Huangtsuishan geothermal site. A conceptual model is constructed and hypothetical exploitation scenarios are explored. The results show that a distance of 300 m is required to avoid a thermal break in 80 years with 120 tons/hour pumped and 90 % reinjected at the Huangtsuishan Geothermal site. A regression formula was provided as a guideline for the minimum required doublet distance for various pumping rates. [ABSTRACT FROM AUTHOR]