Szentlőrinc is home to a renewable energy project that tangibly strengthens the town’s energy independence and security of supply: the town’s district heating system is powered by a geothermal heating plant, which replaces the former natural gas-based district heating by utilizing the thermal energy of locally available thermal water. The system provides geothermal heating for approximately 900 homes, and the solution is also suitable for connecting public institutions.
The technical basis for geothermal heat generation is provided by a pair of wells: the thermal water from the production well, which is approximately 1,800 meters deep, has a temperature of approximately 86–87 °C and a maximum flow rate of approximately 25 l/s. The heat is not fed directly into the district heating loop but is transferred to the district heating network via heat exchangers in the heating plant, thus keeping the thermal water and the district heating medium separate. The system reinjects the cooled thermal water back into the aquifer (the reinjection well has a depth of 1,655 m), which is a key element of long-term sustainable operation. The scale of the Szentlőrinc geothermal heating plant is well illustrated by the fact that project data indicate a capacity of approximately 3 MW and 55,000 GJ, while the district heating side’s heat transfer infrastructure, featuring multi-megawatt heat exchangers, ensures the system’s grid integration.
The greatest advantage of geothermal district heating in Szentlőrinc is that the primary energy requirement for heat production is not tied to imported fuel: local geothermal heat is at the heart of the system’s operation. In operational terms, this means that natural gas consumption is reduced, and with it, the cost component that causes the greatest price and supply exposure in district heating production: the cost of purchasing natural gas. The cost of operating the system is, of course, not “zero”—electricity, maintenance, and operations are required—but the most expensive and volatile element in heat production, the primary fuel, is effectively pushed into the background. In addition, geothermal energy is a weather-independent heat source available 24/7, which is of paramount importance for the predictability of district heating supply.
The transition to renewable heat also has environmental benefits: by replacing fossil fuels, local emissions of air pollutants and greenhouse gases are reduced, which, in the case of a city-wide heating system, is not only a matter of climate protection but also of air quality. The example of Szentlőrinc therefore goes beyond a single investment: it sends the message that in Baranya, renewable energy is not a theoretical goal, but a functioning infrastructure designed with an industrial approach, which creates a more stable heat supply, lower primary energy dependence, and a more competitive local environment.
