How Does Geothermal Drilling Work?

Geothermal well drilling is drilling for geothermal steam and geothermal water. It is an important special technology and a necessary means for exploration and exploitation of geothermal fluids.

Geothermal drilling

For high-temperature geothermal fields, the drilling depth is generally between 500 m and 2,000 m, with a small amount exceeding 2000 m, and most are between 600 and 900 m. For low-temperature conductive geothermal fields, the average depth is 1800 meters, while geological pressure geothermal fields can drill to a depth of 6000 meters. ^[1]

Geothermal drilling geothermal drilling project deployment principles

1. On the basis of fully collecting and analyzing the existing geological, geophysical, and geochemical survey data, select geothermal drilling projects at representative locations for geothermal resource exploration and development;

2. Focus on ascertaining the type, distribution, burial conditions, permeability, geothermal fluid quality, temperature and pressure of major thermal storage, and the production capacity of geothermal wells;

3. The exploration depth can be determined according to the main thermal storage types, burial depths, current mining technology and economic conditions, and market needs. For naturally exposed strip-shaped thermal storage types, the exploration depth is generally controlled within 1000m; the hidden basin-type layered Thermal storage, exploration depth generally does not exceed 4000m;

4. The principle of "combination of exploration and production" should be implemented in geothermal exploration. If geological geological exploration drilling can be exploited as a well, it should be implemented in accordance with the technical requirements of well formation; drilling geological cataloging, logging, completion test and geological data collection of geothermal exploration wells In addition to the implementation of well-forming technical requirements, all geothermal geological data shall be obtained in accordance with the requirements of geological survey.

Basic requirements for geothermal drilling

1. The basic requirements for geothermal drilling include: detailed core cataloging, fracture statistics, collection of rock abrasive samples and chemical analysis samples, etc., to verify the early geothermal mineralization models (such as formations, rocks, structures, and changes in important geological boundaries) Wait).

2. Follow-up drilling temperature measurement and comprehensive temperature measurement, draw the vertical temperature change curve, and scientifically grasp the hot spring water temperature.

Elements of geothermal drilling affecting drilling costs

1. The deeper the well, the higher the cost.

2. Geological factors The complexity of the geological structure during drilling The more complex the geological structure, the more the diameter changes, and the higher the cost.

3. Geographic location of drilling This determines the transportation method and power source of drilling equipment, which in turn affects drilling costs.

4. Drilling rig's footage, power size and opening diameter Generally speaking, the deeper the footage, the greater the required power and the higher the cost.