In the past decade, the oil and gas industry has been progressively shifting towards renewable energy sources. Companies within the sector are exploring a variety of renewable technologies with the goal of achieving carbon neutrality by mid-century. Among these initiatives, geothermal energy has emerged as a significant focus in recent years.

Geothermal well testing, akin to well testing in the oil and gas industry, is crucial for evaluating the economic viability of geothermal projects. Despite the similarities, there are fundamental differences in the hardware used for geothermal and oil-and-gas well testing. This necessitates a re-evaluation of existing geothermal well testing techniques to ensure safety and data integrity.

This paper analyzes the technological gaps in conventional geothermal well testing and introduces advanced well testing technologies and equipment designed to enhance the performance evaluation of geothermal wells. A novel approach to geothermal surface well testing has been developed, significantly improving the efficiency of reservoir performance assessments. This was achieved through a combination of redesigning well testing equipment and workflows, and digitalizing data acquisition, integration, and calculation processes.

A hybrid design, incorporating the best features of both conventional geothermal and oil-and-gas well testing, was employed to ensure operational safety, particularly in controlling unknown H₂S. The use of digital electromagnetic flow meters, alongside traditional weirbox methods for flow rate measurement, was key to ensuring data accuracy and redundancy. The real-time integration of digitalized surface well test data with downhole electrical submersible pumps (ESP) was critical for the rapid evaluation of well test data and making necessary adjustments to the testing program in real-time.

These advancements not only enhance the safety of geothermal well testing operations but also significantly improve data acquisition and the evaluation of well potentials. This paper discusses the development of these advanced well testing technologies, lessons learned, and recommendations for further system improvements.