Project statistics
Installed heating capacity:
• Heat pump: 668 kWth
• Biogas boiler (backup): 1,100 kW
System type:
Low-temperature air to water heat pump and biogas boiler, integrated with brewery wastewater systems
Project model:
BOT – ESCO
Situation before the contract and client requirements
Pivovarna Laško Union (part of the HEINEKEN Company) is Slovenia’s largest brewery and an iconic industrial brand with a 200 hundred years brewing tradition. As part of their long-term decarbonisation strategy, the client aimed to reduce dependence on fossil fuels in their wastewater treatment plant operations, and make better use of available biogas.
An earlier decarbonisation study identified the heating of the bioreactor at the brewery’s wastewater treatment plant in Laško as a key area for improvement — both in terms of energy efficiency and carbon impact.
RESALTA solution
Based on the study findings, Resalta delivered a full modernisation of the bioreactor’s heating system through the BOT–ESCO model.
The solution included:
• Installation of a high-efficiency, low-temperature heat pump (668 kW)
• Replacement of the existing backup system with a new dedicated biogas boiler (1,100 kW)
• A specialised free-flow heat exchanger designed to handle brewery effluent
• Complete mechanical and electrical system integration
The upgrade now allows the full volume of biogas to be redirected toward steam production in the brewery’s industrial process, increasing the share of carbon-neutral process heat and contributing to broader decarbonisation efforts of Pivovarna Laško Union.