Berlin, May 22 – An innovative and nationwide unique geothermal heating system is currently being installed under a sports field at Maikäferpfad in the Charlottenburg-Wilmersdorf district of Berlin. This pioneering project aims to harness the earth’s natural warmth to heat three school buildings and a gymnasium, marking a significant step towards sustainable energy solutions in urban areas.
Geothermal Energy: A Hidden Resource Under Our Feet
Germany boasts approximately 45,000 football and sports pitches, many of which lie atop an untapped energy source. The Berlin initiative demonstrates how geothermal energy can be extracted from beneath a playing field to heat schools, sports halls, and entire neighborhoods. This method utilizes the ground as a natural heat reservoir, absorbing energy during the summer months and releasing it later.
At a depth of about 1.5 meters, 8,800 horizontal high-performance earth collectors are being laid. These collectors extract heat stored in the ground, which even in autumn, maintains temperatures between 12 to 15 degrees Celsius. This temperature is sufficient for heat pumps to efficiently generate the required heating energy for the buildings.
How the Cold District Heating Network Works
The system employs a ‘cold district heating network’ that transports cool environmental energy to the buildings. Unlike traditional hot district heating, the temperature is only raised to the necessary heating level at the buildings themselves, using heat pumps with capacities ranging from 100 to 150 kilowatts. This approach significantly enhances efficiency, as a single kilowatt-hour of electricity can produce approximately four to five kilowatt-hours of heat, double the efficiency of conventional high-temperature district heating.
Michael Roos from the engineering firm Technocare highlights the project’s significance: “This lighthouse project demonstrates the potential of intelligently planned geothermal energy use for public buildings – even in densely populated inner-city areas like Berlin.”
Environmental and Economic Impact
The system is designed to provide an extraction capacity of 477 kilowatts, capable of replacing approximately 118,000 cubic meters of natural gas annually. This translates to about 1.23 gigawatt-hours of energy and an estimated reduction of 180 tons of CO2 emissions each year. This considerable environmental benefit aligns with Berlin’s broader sustainability goals.
The total cost for the Berlin system, including heat pumps and pipelines, is approximately 2.7 million Euros. With potential subsidies covering up to 50 percent, the system is projected to amortize within ten to fifteen years, depending on energy price developments. The earth collectors themselves are designed for a lifespan of up to 100 years, ensuring long-term sustainability and cost-effectiveness.
Sports Pitches: Ideal for Geothermal Projects
Sports pitches are particularly well-suited for such projects due to several factors. They are typically large, relatively flat, and usually free of deep foundations, making them ideal for the installation of flat-panel geothermal collectors. Unlike boreholes, deep drilling is not required, and the stored heat regenerates naturally during the summer.
Furthermore, sports fields undergo regular renovations, providing opportune moments for the installation of earth collectors without significantly disrupting play. The playing surface remains unchanged, with the energy infrastructure hidden beneath.
Considering Germany’s 45,000 football and sports pitches, and an additional 44,000 tennis courts, even partial utilization of these areas could serve as a substantial additional heat source for cities. A single football pitch can deliver between 1.1 and 2.0 gigawatt-hours of thermal energy per year, enough to supply 50 to 80 single-family homes or several public buildings.
Future Outlook and Urban Planning
This concept is of particular interest for municipal heating planning, especially in densely built-up areas where space for new energy infrastructure is often limited. Sports facilities, frequently owned by municipalities, present a readily available solution.
The network, spanning approximately two kilometers, is expected to be completed by the end of 2026. The initiators hope that many more football pitches across Germany will follow the example set by the Maikäferpfad project, contributing to a broader energy transition.
While this project does not replace large-scale district heating plans or heating systems in single-family homes, it serves as a valuable component in the heat supply for dense public buildings, showcasing a viable path towards a more sustainable future.
Source: https://www.chip.de/news/haushalt-garten/waerme-aus-fussballplaetzen-dieses-system-soll-ganze-schulen-beheizen_a148d895-3826-4ce3-9157-81f2f8fa889c.html
