Geothermal energy is the thermal energy contained below the surface of the earth. Typically, the temperature in the earth will be above 100 degrees C below around 4 km deep into the ground. However, the thermal gradients vary dependent on the location. For example, in Iceland and in similar volcanic regions, high earth temperature can be observed at shallow depths. Since there are significant challenges and costs involved in the drilling of geothermal wells, the existing larger geothermal energy plants are found on locations with easy access for the geothermal energy at shallow depths.
During recent years Reelwell has developed novel solutions for well construction. The solutions have potential to solve the key challenges for drilling and completion of deep geothermal wells for heat and electricity production. The solutions are based on the use of DualPipe and new arrangements and procedures for deep well construction. The solutions are expected to enable reduced well costs and improved energy production for the geothermal wells. The solutions can enable geothermal energy production in areas not previously considered suitable.
Unlike other renewable CO2 free energy sources, such as wind- and solar energy, geothermal energy production is not dependent on the weather or the season. Geothermal energy can provide stable clean energy in the form of heat and electrical power day and night, all year around. Geothermal energy plants do not require large surface areas and nature disturbing installations, as the energy is collected from deep wells underground.
The vision of the project is the development of a new solution for drilling and completion of geothermal wells that improve efficiency and solves main challenges of the conventional solutions for geothermal energy production.
The main idea is to utilize novel developments of concentric tubing drilling technology, Dualpipe, for use as a closed loop coaxial heat exchanger for the drilling and completion of wells for geothermal heat extraction. A closed system has an advantage over the conventional open systems because it avoids fluid-rock interactions that clog the well with mineral scale over time. The solution has advantages by reduction of cost of such challenging wells due to reduced NPT and the ability to use low-cost light weight drilling rigs. A main advantage is the ability to improve the length of the production zone of the well and thereby improve the energy production from the wells.
An important application of the proposed geothermal solution is foreseen at the island Svalbard, north of Norway, where the electricity production is currently coming from the burning of coal and diesel. Potential well examples from Svalbard will be considered as a part of a cost, risk and value evaluation to be performed in the project.