Plans in motion to utilise geothermal from abandoned oil wells in Slovenia

Plans in motion to utilise geothermal from abandoned oil wells in Slovenia Hydropower plant by DEM, Slovenia (source: HSE Group)
Alexander Richter 9 Feb 2021

Utilising a Slovenian patent, Slovenian hydropower company together with partners Petrol, dd, Ljubljana and Nafta Lendava, doo is planning an innovative pilot project for the use of geothermal energy in abandoned gas and oil wells.

Hydropower company Dravske elektrarne Maribor (DME), part of HSE Group, the largest producer and seller of electricity from domestic sources on the wholesale market in Slovenia, has announced a partnership that is to help strengthening the position of the largest producer of electricity from renewable energy sources in Slovenia. Together with partners Petrol, dd, Ljubljana and Nafta Lendava, doo DEM plans to establish a pilot geothermal power plant in the Municipality of Lendava. The project will be the first application of a Slovenian patent and can represent an important milestone for the use of geothermal energy in abandoned gas and oil wells in Slovenia and around the world.

Due to its reliability and permanence among renewable energy sources, geothermal energy has a huge potential, as in contrast to wind and solar energy, it is constantly available every day of the year. It has many advantages over traditional fossil fuel-based energy sources; the biggest is that it is clean and safe for the environment, as it does not produce harmful emissions into the environment. The use of geothermal energy can reduce the use of fossil fuels, which also reduces greenhouse gas emissions.

Another advantage is the available geothermal energy reserves, which are practically inexhaustible. Geothermal power plants take up little space, as they are built directly on the energy source. An additional advantage is reliability, as production does not depend on weather conditions; electricity can be produced in a geothermal power plant 24 hours a day, every day of the year. Geothermal energy can be used for heating and cooling or used to produce electricity. The latter require appropriate temperature sources, including tectonic active regions, where abandoned gas wells are often located. There are over ten million of them worldwide, and at least fifteen in Slovenia, which represent the potential for obtaining electricity from geothermal sources.

Pilot project for electricity generation with geothermal gravity heat pipe in well Pg-8

With the above in mind, the project partners are preparing a pilot project for the production of electricity with a geothermal gravity heat pipe in the Pg-8 well in Prekmurje. The purpose of this research – applied pilot project is the practical implementation and use in the world of a completely new method of electricity production with a geothermal gravitational heat pipe, which is the fruit of Slovenian knowledge (patent SI 23618 A).

The pilot project is planned in the settlement of Centiba in the municipality of Lendava. It refers to an already existing but unproductive Pg-8 well. A geothermal gravitational heat pipe produces sufficient heat flux for electricity generation at depths greater than two kilometers. The construction of the gravity heat pipe is carried out in such a way that by exploiting the geothermal heat of the earth in the well, the refrigerant evaporates, the resulting vapors are led to the surface, where they condense and return to the well. The geothermal heat produced in this way can be used for heating and renewable electricity production.

The project envisages the construction of a small pilot power plant with a geothermal gravity heat pipe in a well about three kilometers deep. In case of favourable results of the pilot project, the designed concept can be used on other abandoned wells within Slovenia as well as around the world. The project therefore represents an important milestone for the development of geothermal energy and a contribution to the reduction of pollution from abandoned wells around the world.

General Manager of HSE, Dr. Viktor Vracar welcomes the cooperation: “The HSE Group is the largest producer of electricity, with an 87% share also the largest producer of electricity from renewable sources. These are our future, we are entering the investment cycle of building solar power plants, this year we are setting up larger solar power plants at the Prapretno and Zlatolicje locations, and the procedures for obtaining permits for the construction of the first three hydroelectric power plants on the middle Sava have begun. We believe that the project of using geothermal energy for electricity production will also grow into a successful new investment. ”

The director of DEM, Andrej Tumpej, emphasizes: “The mentioned pilot project is a niche market on a global scale. The concept of using geothermal energy in this way is patented and the exclusive use of the patent is given to the Drava power plants Maribor. The pilot project will be the first application of this patent, which is entirely the fruit of Slovenian knowledge. The implementation, which represents a new step on the path of development and transition to a low-carbon society for all partners, is an added value both for the local community and for the whole of Slovenia. We are especially pleased that we have united the knowledge, experience and interest of Slovenian companies with the support and planned participation of the Municipality of Lendava. ”

Mag. Joze Bajuk, Member of the Management Board of Petrol : “Innovative approaches to solving energy challenges are not unknown to Slovenia, as we have a lot of knowledge and practical experience. Projects like this have great potential to achieve the goals on the path to a low-carbon energy society, which is also one of Petrol’s main strategic priorities. We want as many such integrated partnerships as possible in the energy transition from traditional to cleaner, renewable energy sources. I believe that together with our partners we will successfully carry out the project, which will show the region and beyond a completely new way of using geothermal energy. “

Verena Zidar, director of Nafta Lendava : “We are glad that we at Nafta Lendava have revived a project for which the idea appeared several years ago. An innovative pilot project for the use of geothermal energy in abandoned gas / oil wells in the Municipality of Lendava is a project that will take advantage of local conditions for the use of green energy and influence the development of Nafta Lendava and the Municipality of Lendava.

Source: Company release