Implementation of advanced technical solutions and repurposing of a historic public building under cultural heritage protection to a smart energy center.
Collaboration between Krapina-Zagorje County and REGEA led to the project of restoring a ruined heritage building and its repurposing to a smart building “Bracak Energy Centre”, a multi-purpose education and demonstration centre. Technical features of a the building include: highly efficient biomass boiler using wood pellets (ETA up to 94,9%); Micro CHP for hot water and power production during summer period; Air to water heat pump system for cooling and heating in transitional periods; External wall insulation on the inside and energy efficient windows and doors (U<1,4 W/m2K); Highly efficient internal and external lighting systems (LED and FLUO T5); HVAC system (heating, ventilation and air conditioning); Advanced central monitoring and control system (heating, cooling, energy consumption); Rainwater harvesting system for irrigation of green areas and as wastewater treatment; Electric vehicle charging station and purchase of one electric vehicle; Comprehensive interior conservation works (decoration and replication); Energy efficient appliances for offices and in-house restaurant.
The value of the building is increased by 150% (approximately).

Resources needed

The price of the investment for reconstruction of the building was: 1.160,00 €/m2 without VAT, or in the total amount 1.850.000,00 € without VAT. The average workforce needed for the duration of the site preparation and construction activities consisted of approximately of 30 workers.

Evidence of success

The reconstruction of the building resulted in an upgrade from energy performance certificate (EPC) rating E to rating B with the share of 88% of renewable energy sources. Energy rehabilitation reduced energy consumption for heating by up to 70%, or from the initial 213,0 kWh/m2 to 64,0 kWh/m2. It is expected that at least 40 new jobs will be generated while the reconstruction process itself has boosted the domestic construction sector and improved the skills of workers and professionals.

Difficulties encountered

- Cooperation between key stakeholders is the basis for such project;
- Reconstruction of a historic building in addition to the application of innovative materials and advanced technologies can be very costly;
- Selection of project design, construction and supervisory services is essential.

Potential for learning or transfer

• HOLISTIC APPROACH AND SUSTAINABILITY: not to restore the building to the previous state but to improve it and give it added value (energy savings, renewable energy sources, …);
• Through CO-OPERATION WITH CONSERVATOR it is possible to refurbish the cultural heritage building and to integrate renewable energy sources in it;
• PROJECT PREPARATION is a key of successful project.

Please login to see the expert opinion of this good practice.

Main institution
North-West Croatia Regional Energy Agency
Kontinentalna Hrvatska, Croatia (Hrvatska)
Start Date
September 2015
End Date
December 2016


Please login to contact the author.