Community Research and Development Information Service - CORDIS

Drilling geothermal energy

Geothermal energy is the earth's interior heat with its exploitable resources ranging from shallow ground to hot water and deep rock several kilometres below the earth's surface. While current technologies utilise geothermal resources, the largest portion of which is rock that is heated by molten magma directly below it, - is still almost unused. Modern technology focuses on cost-effective drilling into this rock in order to tap very hot water for environmentally sound energy supply.
Drilling geothermal energy
A Slovakian company has recently developed a new thermal energy drilling technology that is based on key research accomplishments achieved worldwide. The so-called LithoJet technology may be used for drilling horizontal and vertical holes, as well as combinations of both. In addition, the new instrument is capable of reaching rocks found in extremely deep underground regions, even more than 10km, in the most cost-effective way.

The instrument, capable of melting rock at high temperatures, is fed by low quantities of electrical energy, which is further transformed into high thermal energy. Using a mediated direct transmission method, the instrument transmits heat without significant loss of energy and realises the fast melting of rocks. The produced thermal tensions create fractures in the rock, assisting in creating the molten material that results.

In order to support the drilling process, alternative processes have also been included such as a combustion process that generates steam under high pressure. The steam guides the molten material at a lower temperature to the drilled surface, leaving behind a hole that features a smooth and glassy crust. At the same time the combustion process is an ecologically sound process that doesn't affect the environment of the drilled rock.

The successfully tested prototype has proven to be a promising technology for drilling deeper holes in a cost-efficient and rapid way without any environmentally unfriendly results. Using this fracturing concept, LithoJet technology may be used for creating permeability in hard rocks for enabling hot water circulation for geothermal energy supply. Furthermore, the technology may also find possible applications in mineral oil, tunnel construction and other mining industries.
Record Number: 80790 / Last updated on: 2005-09-18
Domain: Energy