About geothermal project

Geothermal energy is a clean and continuously available renewable resource whose output is not dependent on the time of year, time of day or weather fluctuations. The boreholes themselves are not space-intensive - thanks to ‘directional drilling’ technology, several boreholes can be drilled at once from a single 50 x 50 m site, even though the boreholes may be hundreds of metres apart in depth. Compared to traditional energy sources, it has negligible greenhouse gas emissions, it does not disturb the landscape or local ecosystems compared to wind and hydroelectric power, and its installation and maintenance does not require many precious minerals from politically and environmentally problematic sources. Moreover, geothermal energy for heating and direct use is available everywhere in the world.

In Litoměřice a drilling of 2 km deep pilot borehole has been initiated by the town representatives in 2004. In 2019, the RINGEN research centre was opened here, focusing on the study of geothermal energy. Therefore, there were ideal conditions for the creation of a project of this kind.

A geothermal project follows the same process as mineral exploration. Regional exploration identifies promising sites from publicly available data from geological mapping, existing boreholes, etc. These sites are then subject to detailed exploration, which usually consists of a combination of several surface geophysical measurements and the excavation of exploratory boreholes from which rock and fluid samples are taken and further geophysical measurements are made. This is followed by a resource evaluation phase where additional measurements are used to determine the exact location, size and performance of the resource and any risks and complications to its extraction. If this phase also yields positive results (i.e. the raw material - in this case heat - is sufficiently concentrated and economically recoverable), the actual implementation phase comes next, i.e. the drilling and casing of injection and production wells and the construction of the necessary infrastructure on the surface. At the end of the lifetime of any mining or energy project, there should also be a remediation phase, i.e. restoration to the original pre-implementation state or as close to it as possible (e.g. backfilling of fractures, cementing of boreholes, etc.). The lifetime of geothermal projects is currently measured in the upper decades. For example, the oldest geothermal project in the world, Larderello in Italy, has been in operation for 120 years.

For the local community, the new geothermal project will bring not only clean energy for heat and power generation, but also new jobs, potential use of brownfield sites and an increase in the attractiveness of their community.

The underground technologies include three arrays of shallow boreholes that will be used to store thermal energy in the rock environment. These underground thermal storage fields, called BTES (Borehole Thermal Energy Storage), will have depths of 100, 200 and 400 m. There will also be two deep boreholes that will be used to extract geothermal energy from a depth of 3 to 3,5 km, where the temperature reaches about 90 °C.

Drilling technology is a relatively complex discipline that reflects the variety of geological conditions in which drilling is carried out. In very simplified terms, our planned drilling can be carried out in a number of basic ways or a combination of ways. Particularly in dry and solid crystalline rocks, the fastest way to drill is with a submersible hammer with air wash. A slower method, but applicable in a wide range of environments, is rotary drilling with liquid wash, which will be used for most of the boreholes in Litoměřice. Rotary drilling uses a wide range of drill heads and can also be modified to take drill core. As this project places great demands on precision drilling, sophisticated steerable drilling technology will also be used, which allows the drill hole to be corrected in the case it deviates from the desired path or to change the drilling direction in any way (e.g. to a horizontal direction in the case of deep wells).

SYNERGYS' above-ground technologies will include solar panels of various types, a hydrogen electrolyser, hydrogen cogeneration technologies, a low-temperature grid simulator and a set of low- and high-temperature heat pumps, all connected to seasonal energy storage to form a comprehensive energy system for centralised renewable heat supply.

Because each of them uses different technologies. The fact that they work independently will allow us to adjust their parameters regardless of the functioning of the whole. At the same time, all four systems are connected by a low-temperature heat network simulator, from which renewable heat can be pumped to the existing district heating network in Litoměřice.

The green hydrogen will be used for seasonal energy storage for later use to produce electricity and heat. This is its major advantage over short-term storage of electricity in battery storage.

The thermal output of the systems is assumed to be 2 MW, which is enough to cover the basic heat consumption of district heating system (DHS) in Litoměřice. The peak output of DHS in Litoměřice is around 40 MW.