Geothermal energy in industry

Geothermal energy is the thermal energy stored within the Earth. Its source lies in the processes occurring in the planet’s core and mantle, including the natural decay of radioactive elements. In industrial and energy applications, geothermal energy is mainly harnessed from the heat contained in underground water and steam found in geological layers. The temperature of these resources depends on depth and local geological conditions — in Poland, geothermal waters typically range from 20°C to 100°C, though in some regions, they can exceed 150°C.

For comparison, the world’s largest geothermal resources are mainly found in volcanically and tectonically active regions:

• Iceland (70–300°C) – located on a mid-ocean ridge rift zone, geothermal energy covers a significant share of the country’s heat and electricity demand,
• Indonesia (150–350°C) – an archipelago situated at the junction of the Pacific and Eurasian tectonic plates, with the world’s largest technical potential for geothermal energy use,
• Philippines (150–300°C) – one of the world’s leading producers of geothermal electricity; geothermal power plants supply a major portion of the national energy mix,
• Kenya (150–350°C) – the Great Rift Valley region has high geothermal temperatures and stable pressure, enabling efficient power generation,
• USA (California, Nevada, Wyoming, Oregon) (200–350°C) – particularly California’s The Geysers, the largest geothermal power complex in the world,
• USA (California, Nevada, Wyoming, Oregon) (200–350°C) – particularly California’s The Geysers, the largest geothermal power complex in the world,
• Italy (150–220°C) – especially Tuscany, home to Larderello, the world’s first geothermal power plant.

Through geothermal drilling, it is possible to extract an energy carrier in the form of hot water or steam, which can then be directed into heating or industrial systems. Unlike solar or wind energy, geothermal energy is stable — available around the clock and independent of weather conditions.

Industry is among the largest consumers of energy. Using geothermal resources can significantly reduce thermal energy costs, and in some cases, electricity costs as well. Applications can be divided into several categories:

• low-temperature processes (up to 120°C) – such as drying wood, agricultural and food products, fermentation in brewing, dairy processing, or heating process water,
• medium-temperature processes (120–180°C) – production of process steam, evaporation in chemical and pulp-and-paper industries, cleaning, and sterilization,
• high-temperature processes (>180°C) – feasible mainly in regions with particularly hot resources, where water or steam can power turbines to generate electricity, later reused for industrial heating.

Additionally, geothermal energy can support industrial cooling through absorption chillers, as well as heating and air conditioning in production halls. Combining geothermal systems with trigeneration setups (producing heat, cooling, and electricity) is particularly attractive, as it maximizes energy efficiency.

Implementing geothermal energy in industrial plants requires appropriate technical infrastructure and upfront investment. The key components include:

• geothermal wells – one or more production and reinjection wells that allow geothermal water circulation,
• pipeline and heat exchanger systems that transfer energy from geothermal fluids to industrial processes,
• supporting installations – such as pumps, filtration units, and systems protecting against corrosion and mineral scaling,
• heat pumps (optional) – enabling temperature boosting when the natural geothermal source temperature is too low for the process,
• cogeneration or trigeneration systems (optional) – allowing simultaneous production of electricity, heat, and cooling.

The cost of a geothermal installation largely depends on drilling depth and resource quality. Such investments typically require several to over a dozen years of operation to achieve full payback, but they later offer low operating costs and high supply stability.

In Poland, geothermal energy is primarily used for district heating and balneology (therapeutic spa applications):

• Podhale – the oldest and most developed geothermal source in Poland. Geothermal heat is mainly used in district heating networks, but also by service and recreational facilities;
• Bańska Niżna, Mszczonów, Uniejów, Lądek-Zdrój – geothermal installations provide heat for thermal pools, hotels, recreational facilities, and urban heating;
• Stargard and Pyrzyce – geothermal energy is being developed here with a focus on the local food and agro-processing industries.

Poland has significant geothermal resources — it is estimated that up to 80% of the country’s area has the potential to use subsurface heat. However, these are mostly low-temperature resources (around 20–100°C). The country’s geothermal water resources are estimated to contain energy roughly 300 times greater than Poland’s annual demand — about 35 billion tonnes of oil equivalent (toe). The most promising areas for geothermal development are Podhale, the Polish Lowlands, and the Szczecin–Baltic region.

Several factors are boosting the potential for industrial geothermal projects:

• rising energy prices and the need for stable, local heat sources,
• EU climate regulations and the growing importance of industrial decarbonization,
• the ability to combine geothermal energy with other renewable technologies, such as heat pumps or photovoltaics,
• increasing experience of Polish companies in drilling and installation construction.

In the coming decade, more industry-oriented geothermal projects are expected, especially in energy-intensive but low-temperature sectors such as the food, chemical, and paper industries.

Geothermal energy is classified as a renewable energy source and is considered a form of green energy. Its operation generates minimal greenhouse gas emissions — mainly during installation construction and in the process of pumping and transporting water. Unlike fossil fuels, it does not produce continuous CO₂ emissions during use.

In some cases, geothermal waters may release small amounts of harmful gases (e.g., hydrogen sulfide or carbon dioxide), but these can be neutralized or safely reduced through degassing or absorption processes, especially in spa regions. As a result, geothermal energy is regarded as one of the most environmentally friendly energy sources, capable of helping industry meet climate goals and improve ESG performance indicators.

Geothermal energy in industry holds great potential, though it remains relatively underdeveloped in Poland. Its supply stability, low operating costs, and minimal environmental impact make it a valuable complement to the national energy mix. Advances in drilling technologies and growing financial support for geothermal projects increase the likelihood that more companies will invest in this energy source in the coming years. While implementation requires substantial infrastructure and capital expenditure, geothermal energy can yield long-term financial benefits, improve energy security, and support industrial decarbonization strategies.