The Polish city of Biłgoraj has commissioned a heat pump installation that recovers thermal energy from treated wastewater and uses it to supply its municipal heating network.
The project was developed by Metrolog under a design-and-build contract, with an investment exceeding 12 million Polish złoty (PLN). The system currently provides approximately 20% of the energy required by the local heating network.
Treated Wastewater Provides a Consistent Heat Source
The installation operates through a water-to-water heat pump circuit located at the outlet of the city’s wastewater treatment plant.
It uses the relatively stable temperature of treated wastewater to provide a continuous source of thermal energy throughout the year. This allows the system to operate consistently, unlike renewable sources such as wind and solar, whose energy production can fluctuate.
The facility is also connected to a photovoltaic installation with a capacity of nearly 190 kWh, reducing its dependence on electricity supplied by the external grid.
The project received funding through the Polish Plan state fund.
Heat Pumps Reduce Reliance on Fossil-Fuel Boilers
The wastewater heat recovery system is designed to replace a significant portion of the energy previously supplied by fossil-fuel boilers, particularly during periods between the main heating seasons.
During these shoulder seasons, it can almost completely replace conventional heating for domestic hot water production.
In winter, when heating demand reaches its highest levels, the installation operates as a supplementary source of energy, reducing the load on traditional heating equipment and improving the overall efficiency of the municipal network.
The system is intended to support the city’s compliance with European heating standards.
Metrolog Previously Developed a Similar Installation in Szlachecin
The Biłgoraj project follows an earlier wastewater heat recovery installation completed by Metrolog in 2020 in Szlachecin for Veolia Energia Poznań.
That system captures thermal energy from wastewater supplied by Aquanet and combines it with gas-based cogeneration in a single circuit.
The installation has a total thermal capacity of 2.9 megawatts and was designed to reduce the operating burden on the coal-fired power plant in Bełchatów.
Both Projects Receive Construction Industry Recognition
The Biłgoraj and Szlachecin installations have both received the Construction of the Year award, known in Poland as Budowa Roku.
The awards were presented by the Polish Association of Civil Engineers and Technicians and the Ministry of Development and Technology.
Michał Cholewa, Metrolog’s Development and Technology Director, said the operational value of the projects came from integrating water, heating and energy infrastructure to reduce dependence on hydrocarbons in local utility networks.
Metrolog’s Role in Energy Efficiency Projects
Metrolog Sp. z o.o. was established in 1991 and specialises in thermal energy systems and cogeneration.
The company is part of Elevion Group, which operates projects focused on decarbonisation and energy efficiency across 13 European markets.
Its Biłgoraj installation adds to the company’s work on recovering energy from wastewater for use in municipal heating systems.
