Leveraging excess heat from the Warsaw metro

Poland has the highest share of coal in total energy supply and demand of all International Energy Agency (IEA) member countries.

To address this, the Polish government has adopted the Energy Policy of Poland until 2040 (EPP2040), a comprehensive agenda for creating a just transition to a zero-emission energy system. One key target is to reduce the country’s reliance on coal, aiming “to meet heating demand for all households in a zero- or low-emission manner.”

Warsaw has the eyes of Europe upon it, and a golden opportunity to transform its energy system into a modernized, efficient system built for the era of renewables.

Every year, a combined 62 GWh of heat is wasted from the metro stations. This is the equivalent to the heating demand for the homes of over 14,000 Polish people for a year. However, the majority of this metro's excess heat can be recovered and integrated into the district heating system to heat the homes, businesses, and domestic hot water of Warsaw.

If Warsaw captures and uses the excess heat from the metro, the burning of fossil fuels from the Siekierki and Żerań power stations can be reduced. Now, the main purpose of these combined heat and power (CHP) stations is to produce electricity by burning fossil fuels. Much of the waste heat from this process is captured and distributed in the district heating grid.

Warsaw can save about 42,000 tons of CO2e per year by capturing the excess heat from the metro system if the electricity to power the heat pumps and supplement the reduced electricity production from the CHPs is provided with renewable energy. That is equivalent to the annual carbon footprint of about 6,300 Polish citizens.