Geothermal district heating in Podhale

Poland

Jun 14

Overview

The rural Podhale region in Southern Poland is home to one of Europe's largest geothermal heating networks, operational since 1993, and significantly expanded in 2020. Initiated by the Polish Academy of Sciences, the project began in Banska Nizna village and now spans several towns, including Zakopane and Nowy Targ.

The system combines a Geothermal Base Load Plant in Banska Nizna Szaflary and a Gas and Oil Peak Load Plant in Zakopane. Initially, the gas plant served as the main source until geothermal heat became predominant in 2001.

By 2018, around 1,600 users were connected, meeting 35% of Zakopane's heat demand. The network expanded to nearly 1,700 users by 2020, covering a 115 km area that includes Zakopane, Szaflary, Bialy Dunajec, and Poronin.

This network not only provides heating but also supplies water to recreation centers and supports innovative uses like heating football pitches and melting snow in parking areas. The Podhale geothermal system stands as a model for sustainable energy in Europe.

Historic development

The first deep exploration well in the Podhale region, Zakopane IG-1, was drilled in 1963, revealing several geothermal aquifers, with the most productive found in Jurassic marls and limestones. Throughout the 1970s and 1980s, additional wells were drilled along the southern boundary of the Podhale system.

A significant milestone was achieved between 1979 and 1981 with the drilling of the Banska IG-1 well, which confirmed the presence of favorable geothermal aquifers. From 1987 to 1995, a comprehensive investigation involving multiple scientific institutions assessed the geothermal water reserves, leading to the drilling of five deep wells that validated the potential of the geothermal reservoirs.

In 1989, Poland's first Experimental Geothermal Plant in Banska-Bialy Dunajec was established, and by the 1993/94 heating season, it began supplying geothermal heat to six buildings. Following the successful pilot stage, Geotermia Podhalanska S.A. was founded in 1994 to oversee the construction of the regional geothermal heating network, with support from local communities, the Polish Academy of Sciences, and other stakeholders.

In 1998, Geotermia Podhalanska S.A. merged with the municipal District Heating Company in Zakopane to further develop the project. Continued efforts to optimize and expand the system took place between 2016 and 2018.

Policy drivers

Several public programs have been launched to promote the utilization of geothermal energy in Poland, aiming to expand the recognition and use of these resources. As a result, more district heating systems are expected to be implemented, with only six currently operational.

The National Fund for Environmental Protection and Water Management (NFOŚiGW) is focused on consolidating these efforts through its "Polish Geothermal Plus" program. This initiative aims to increase the use of various geothermal resources across Poland, driven by recent scientific research on the country's geothermal potential.

The program allocates a total of 600 million PLN (140 million EUR) in subsidies, split equally between non-returnable (up to 300 million PLN or 70 million EUR) and returnable forms of support.

Investment history

The investment is financed from the Polish and foreign sources including share capital, grants, loans, and credits. They are as follows:

Polish sources: the capital of the company PEC Geotermia Podhalanska S.A.; Ekofund, the National Fund of Environmental Protection and Water Management

Bank PKO;

Foreign sources: the World Bank, PHARE EU, Large-Scale Infrastructure Projects EU, the Global Environment Facility (GEF); credits: the Bank of Environmental Protection, the Danish Environmental Protection Agency (DEPA).

The capital expenditures over the period of 1995 – 2002 totalled about 212 million zl (about 53 million USD). It should be mentioned that a part of means comes from Ekofund. This fund was established on the basis of the Polish foreign dept extinguished for ecological purposes.

The great benefit for Podhale is a high percentage of grants (near 50%) in the financing.

In July 2020, geothermal heating operator Geotermia Podhalanska announced it will increase its capacity by 16 MW following the signing of a new contract for granting subsidies in the form of a grant and a loan for the execution of a new reinjection well and the reconstruction of the existing well.

The total cost of the project expansion in 2020 is PLN 42.8 million (EUR 10 million).

Co-financing in the form of a subsidy amounts to PLN 13.9 million, which is for 40% eligible expenses.

The remaining 60% expenditure in the amount of PLN 20.8 million will be financed in the form of a loan granted by the National Fund for Environmental Protection and Water Management on preferential terms.

Prior to the geothermal project, only the part of the town of Zakopane was provided with a heating network. Therefore, most of dwellings both in Zakopane and Podhale’s villages were heated by their individual heat source. Due to the great area of the developed project, the construction of the heating networks involved a major amount of expenditures (Dlugosz, 2003). A 90/50°C heating network between energy sources and consumers has been built practically from scratch. The main pipeline towards the town of Zakopane is built of pre-insulated pipes with small heat losses.

Technical details

In the exploited Podhale geothermal system, the aquifer ranges from 2048 to 2113 meters (top) to 2394 to 3340 meters (bottom) in depth. Temperatures in the main aquifer at depths of 2-3.2 km reach 80-100°C, with wellhead temperatures peaking at 86-93°C. Deeper within the system, temperatures in the formation measure 120-130°C at depths of 4.5-4.8 km. The average geothermal gradient varies from 1.9 to 2.3°C per 100 meters.

The heating network spans 115 km and serves Zakopane, Szaflary, Bialy Dunajec, and Poronin. As of 2004, the installed geothermal capacity was 38 MWt (totaling 77.9 MWth) from two production wells: PGP-1 and IG-1, with a combined discharge capability of 670 m3/h of 82-87°C water.

Plate heat exchangers facilitate heat transfer to the district heating water, each providing about 7 MWt with geothermal water cooling by 25-30°C. The cooled water is then reinjected into the reservoir through two injection wells located 1.2 to 1.7 km from the production wells, managed by a pumping station.

The plant also includes a circulation water treatment system handling approximately 50 m3/h, an expansion system safeguarding specific pressure zones, and circulation pumps delivering 3 x 470 m3/h of network water to Zakopane.

Network water heated to 70-83°C is distributed through transmission and distribution pipelines to individual receivers equipped with node heat exchangers. Cooled geothermal water, cooled by no more than 25-30°C, is routed back to the reservoir via a pipeline and pumping station.

By the end of 2003, over 400 small individual consumers, 110 large-scale receivers, and 25 local coal-fired space heating plants, serving more than 100 apartment blocks, were connected to the geothermal network.

Additionally, the operational cascaded system supports:

Space heating and domestic hot water supply to the buildings of the PAS MEERI Geothermal Laboratory

Wood drying

Greenhouses

Stenothermal fish farming

Foil tunnels for heated soil vegetable cultivation.

Heat consumers

Geothermal heat consumers in the Podhale region are divided into two main groups based on thermal power demand:

Individual Households: These have capacities from several to a dozen kilowatts and are equipped with compact dual-function plate heat exchangers for both central heating and domestic water.

Medium and Large Consumers: This group includes boarding houses, offices, schools, public buildings, and larger structures previously heated by coal boilers. They use compact dual-function plate heat exchangers with automatic weather-sensitive systems for features like night temperature drops and wind impact adjustments. All heat exchangers have heat meters.

In 2004, geothermal heat was priced slightly higher than coal heat but lower than gas heat. When labor costs are included, geothermal and coal heating costs are nearly the same. The cost of producing 1 GJ of heat at the Geothermal Base Load Plant in Banska Nizna – Szaflary is about 10 PLN (2.5 USD). Electricity and natural gas account for only 25% of these costs, while 10% is due to the new property tax introduced in 2002.

The project had to gain social approval for necessary technical changes and related costs. Consumers appreciate geothermal heat for its:

Comfort of operation

Greater control over indoor temperature

Ability to monitor energy consumption for potential savings

Reduction of local air pollution

Environmental protection

The project aims to replace significant amounts of fossil fuels, especially coal, with geothermal energy for space heating and domestic hot water.

Podhale has long suffered from severe pollution due to extensive coal burning for heating, with the heating season lasting up to 9 months. Since the late 1980s, the regional geothermal heating network has been crucial in halting the degradation of the Podhale ecosystem and promoting sustainable environmental management.

The project has significantly reduced emissions of CO, SO2, and particulate matter. In Zakopane, the introduction of geothermal heating between 1998 and 2002 led to a 50% reduction in annual average concentrations of PM10 and SO2. During the winter heating season of 2001/2002, SO2 levels dropped by 67% compared to 1994-1998 levels before geothermal heating was implemented.

The primary motivation for the geothermal project has been its ecological benefits. By replacing coal and coke, the project has substantially decreased emissions, achieving reductions that would be impossible without the geothermal system.

Since 2018, Westland has been home to a geothermal project, Trias Westland, which serves both greenhouse horticulture businesses and residential buildings. Trias Westland, a collaborative initiative by and for greenhouse horticultural entrepreneurs, embodies the community's commitment to sustainable energy. Through a cooperative model, these companies join forces with major regional partners to transition towards a greener, more sustainable energy future.

Summary

Depth of drilling: 2 production wells: Banksa IG-1 5261m and Banksa PGP-1 3242m, and two injection wells; Bialy Dunajec PAN-1 2394m and Bialy Dunajec PGP-2 2450m.

Geothermal power: Total 80,5 incl: 40.7 MWt geoth., 39.8 MWt gas peak. In 2004, its installed capacity was 38 MWt (total 77.9 MWth)

Temperature of the water drawn: Banksa IG-1: 82˚C Banksa PGP-1: 87 ˚C

Units covered: In 2018 ca. 1600 receivers were connected to geothermal district heating (mostly in Zakopane – the main city of that region and main heat market; geothermal district heating met ca. 35% of its heat demand). Part of the spent geothermal water was injected back by 2 wells while another part supplied 2 recreation centres.

Total amount of investments: capital expenditures 1995-2002 (Dlugosz, 2003): 212 million zl (about 53 million USD). The total cost of the project expansion in 2020 is PLN 42.8 million (EUR 10 million).

Emissions avoided: Annual average concentrations of particulate matter (PM10) and SO2 have dropped by about 50%. Moreover, during winter heating season of 2001/2002 the SO2 concentration dropped down by 67% as compared to the situation in 1994-1998 prior to geothermal heating initiation in Zakopane.