Sustainability investment in the Zalakaros Spa

By project DETOCS

Published on 25 February 2025

Hungary

About this good practice

The Zalakaros Spa was opened in 1960. Its waters are fed by the 96°C thermal water from a depth of 2700 metres. The spa is one of the country's most popular tourist attractions, welcoming nearly 600,000 visitors in 2023.

The cost of running the spa is dominated by energy costs, in addition to human resources. Until 2021, the annual consumption of natural gas, which amounted to around 260,000 m3 per year, was only 40 million HUF (100,000 EUR), but by 2022, due to the energy crisis, it rose to 280 million HUF (700,000 EUR).

The increased energy prices have therefore risen the running costs to such an extent that the problem could not be effectively tackled by traditional means (e.g. closing parts of the building, replacing windows and doors).The solution was to build a geothermal energy supply system that uses the available thermal water to heat the buildings.

In order to use the thermal water for heating purposes, a system had to be built that would both prevent the high mineral content of the water from precipitating in the system and keep the water in a liquid state (i.e. flowing rather than "knocking") when it reached the surface.

As a first step, cold water was mixed with water from a depth of 2,700 metres at a depth of 400 metres, and a cooling-mixing and inhibitor dosing system was installed to prevent mineral deposition. In addition, the degasification tank was insulated, and a double heat exchanger was installed to ensure daily maintenance of the system.

Expert opinion

The Zalakaros Spa, a prominent thermal bath in Hungary, has undertaken significant sustainability investments to enhance its environmental performance and promote eco-friendly tourism. The practice aligns with EU policy goals including climate neutrality by 2050. Other regions can learn valuable lessons from the practice, including that sustainable tourism interventions can help to attract environmentally conscious travellers while also reducing operational costs and high energy bills.

Simon Hunkin

Works at Interreg Europe Policy Learning Platform

Resources needed

The total cost of the project was EUR 538 000, which was entirely carried out as an own investment by Zalakaros Bath Ltd.. The expertise required for operation is provided by the contractor under an operation contract.

Evidence of success

90-92% of annual natural gas consumption is replaced by geothermal energy. As a result, in 2023:
- annual natural gas consumption: 25 000 m3
- expenditure on natural gas consumption: 11 500 000 HUF (29 000 EUR)
- Savings achieved: HUF 130 000 000 (EUR 325 000)
Performance of the installed system:
- 17 m3/h for heating purposes
- Available thermal capacity: 711 kW

Potential for learning or transfer

- The installed system made it possible to use the thermal water with high mineral content for heating purposes
- The system was made using the highest quality materials to ensure long-term operation
- Water quality improved
- As the system is completely closed, microbiological risks were avoided
- Reduced dependence on fossil energy
- Further potential for the use of thermal energy for cooling purposes
- By including additional thermal wells, the thermal energy extracted from them can be sold to hotels and businesses in the area, providing the spa with a steady and fixed income and allowing operators to obtain energy at a more favourable price.
- The next step will be the installation of a solar panel system at the spa, which will reduce annual electricity consumption by more than 16% This is approximately 350,000 kWh, which is worth 3.5-4 million HUF (9,000-10,000 EUR) at current prices.