Highlights

• EC Żerań will use a heat recovery system to reduce CO₂ emissions and cut the costs of purchasing emission allowances.
• The project will enable the recovery of thermal energy of up to 50 MWt, which meets the needs of around 20,000 dwellings in Warsaw.
• The investment in Żerań involves the construction of two heat pumps utilising a stable and local energy source: raw sewage from the nearby pumping station in Białołęka, owned by Warsaw Municipal Water and Sewerage Company (MPWiK).
• Thanks to the investment in Żerań, an additional 3% of renewable heat will be fed into Warsaw’s district heating system.

The project will enable the supply of green heat to around 20,000 households, using waste heat recovered from sewage. This demonstrates that it is possible to effectively combine the city’s sewage treatment with the production of heat for residents, creating a circular system. Today’s agreement is part of a major investment plan: the first two 50 MW heat pumps are just the beginning of a larger system, which in subsequent stages is also set to cover Siekierki and Czajka. In this way, we are modernising the whole of Warsaw

– said Paulina Hennig-Kloska, Minister of Climate and Environment, during the conference.

Funding from the NFEP&WM amounting to PLN 125.4 million will partially finance the construction of a wastewater heat recovery system, which will be technologically linked to the EC Żerań via the district water network, the electrical connection (including power supply for the heat pump drives) and telecommunications installations. The entire heat flow from the installation will be directed to the EC Żerań Combined Heat and Power Plant to achieve the appropriate parameters required by the district heating network, and then to the Warsaw network. Thanks to this investment, it will be possible to recover thermal energy of up to 50 MWt, which will meet the heating demand for approximately 20,000 dwellings in Warsaw.

The construction of a wastewater heat recovery system is a modern and groundbreaking solution that allows thermal energy to be harnessed from an already available source – wastewater. We are delighted that, thanks to this funding, we will be able to implement a technology that will not only reduce fuel consumption but also help us meet growing environmental requirements. This is an investment that is genuinely changing the way we think about energy production in Warsaw and opening the door to further ambitious projects

– said Andrzej Gajewski, CEO of ORLEN Termika.

Recovering waste heat from untreated sewage is a solution that will allow more heat to be supplied to consumers without the need to increase production, which will result in more sustainable resource management. This new source will reduce water consumption for cooling purposes and contribute to a reduction in CO2 emissions and other pollutants, thereby improving air quality in the capital city. On an annual basis, this project will lead to:

• the generation of 320,497 GJ of thermal energy from renewable sources,
• a reduction in CO2 emissions of approx. 62,682 tonnes (a decrease in CO2 emissions of over 3%).

Thanks to this investment, EC ŻERAŃ will begin using renewable energy sources for the first time, whilst significantly reducing its consumption of coal by 679,822 GJ and natural gas by 30,632 GJ.

The investment will be carried out in cooperation with the Miejskie Przedsiębiorstwo Wodociągów i Kanalizacji w m.st. Warszawie S.A. (Warsaw Municipal Water and Sewerage Company, MPWiK). It will be implemented between 2026 and 2029. In addition to the investment at the Żerań Pumping Station, similar investments are planned for launch in 2029 at the following locations: EC Siekierki Combined Heat and Power Plant and the ‘Pruszków’ Wastewater Treatment Plant, and in 2030 at the ‘Czajka’ Wastewater Treatment Plant. The total thermal capacity of the heat pumps built in the first phase, i.e. by the end of 2030, will amount to approximately 182 MWt. In the future, following the expansion by 2034, the thermal capacity will increase to nearly 250 MWt. These will be among the largest investments in heat pump technology utilising municipal wastewater in Europe.

The construction of a heat recovery system using untreated wastewater is a key part of the modernisation plan for EC Żerań – the largest such project in the history of Warsaw’s CHP plants. Its implementation already began in 2021, when a combined cycle gas turbine (CCGT) and two peak-load gas-fired boiler rooms were commissioned. The aim is to completely phase out coal combustion by 2035 and decommission all generation units powered by this fuel.

Minister Paulina Hennig-Kloska also discussed, at the EC Żerań, the project – co-financed by the NFEP&WM under the ‘Energia Plus’ priority programme – to construct what is currently Poland’s largest thermal energy storage (water reservoir), with a capacity of approximately 61,000 m³. The aim of this project is to reduce the negative impact on the environment, including improving air quality by increasing the energy efficiency of generation processes resulting from the balancing of the EC Żerań's operation over a 24-hour cycle (shifting production to more efficient units and increasing cogeneration output), whilst simultaneously reducing the amount of fuel burned. The value of the investment is over PLN 152 million, and the loan from the NFEP&WM is over PLN 129 million.