Alba Iulia, located in Central Romania, is one of the oldest settlements in the country. The rich history of the town merges with a bold vision of becoming a smart, sustainable, resilient, and climate-neutral city. Alba Iulia is committed to reducing its greenhouse gas emissions by 40% by 2030 and becoming climate-neutral by 2050.
One of the greatest challenges in Alba Iulia is improving the energy efficiency of buildings and increasing the use of renewable energy sources. The city is continuously experimenting with new technical solutions to address this challenge, especially in large public buildings like the Olympic swimming pool or the Residential Home for the Elderly.
The latter is the third largest municipal energy consumer in Alba Iulia, with annual energy consumption ranging between 1600 and 1900 MWh/year. It is a big, atypical three-story building (approx. 9600 sq. meters) built at the end of the 1990s and early 2000s. It houses more than 100 seniors and staff.
The early attempts to improve the building's energy efficiency occurred between 2010 and 2011. The city installed the first photovoltaic panels and a solar thermal system for hot water and renovated the building by enveloping the structure with 10 cm of insulation, changing the windows, and putting shading on balconies.
With financial support from the EEA and Norway Grants, Alba Iulia launched a more ambitious energy efficiency project for the Residential Home for the Elderly in 2022. The new project allowed the implementation of a complex solution integrating a high-capacity geothermal system with the refurbished solar thermal and photovoltaic systems already installed but not functioning correctly anymore. The technical solutions and upgrades include:
- A geothermal system, including 80 wells, four storage/heat exchange pumps, and three indoor heat pumps;
- New heating and cooling distribution system, including ventiloconvectors, individual room temperature controls, ventilation with recovery in the main meeting/activities room, and towel radiators in the bathrooms to ensure appropriate indoor climate and comfort for seniors;
- Rehabilitation of the solar thermal system to produce hot water and providing heat for ground energy storage;
- New auxiliary thermal equipment and installations (two new, digitally controlled high efficiency condensing boilers, storage vessels, heat exchangers, electric valves, expansion vessels, meters);
- An advanced building energy management system (BEMS) that orchestrates the operation of equipment according to external conditions and internal needs, thereby optimising the use of energy resources.
According to the energy audit, the estimations related to the energy efficiency of the rehabilitated building are close to the Nearly Zero Energy Buildings (nZEB) standards. The installed system provides approximately 70% of the thermal requirement from renewable sources, significantly reducing environmental impact and promoting sustainability. Preliminary results show a possible energy production of over 1100 MWh/year from geothermal renewable sources and a reduction of 60% of energy consumption and CO2 emissions. The residents of the Residential Home for the Elderly are also happy with the improved indoor climate and amenities.
Key Drivers
- Strategic priority: Improving the energy efficiency of the Home for the Elderly was identified as one of the top priorities in the Energy Efficiency Improvement Program of Alba Iulia.
- Funding: The implementation of the project was possible with financial support from the EEA and Norway Grants under the Energy Programme in Romania. The total budget of the project was more than 1.2M EUR. The Municipality of Alba Iulia covered 15% of the eligible project costs and all non-eligible project costs.
- Collaboration: The close partnership with Societatea de Inginerie Sisteme București (SIS) and other relevant partners was essential for the project's success. Collaborating with experienced subcontractors and having good technical supervision ensured an efficient and flexible work process, allowing the implementation of the envisioned complex solutions on time.
- Social responsibility: The project aimed not only to improve the energy efficiency of the building but also to create a warmer and more welcoming environment for the residents of the elderly home. Through this project, the city emphasised their commitment to social responsibility and to enhancing the quality of life of the elderly residents in Alba Iulia.
Challenges and barriers
Technical:
- Geophysical conditions: Alba Iulia doesn't have specific geothermal conditions favourable for geothermal solutions. Moreover, the thermal response test revealed that the conditions are slightly worse than initially estimated, and wells could not be drilled deeper than 102 meters. Consequently, the project required an increase in the number of wells from 60 to 80 to implement the project.
- Rehabilitation of the old systems: Additional technical challenges arose when integrating the existing photovoltaic and thermal systems with the new geothermal and automation (BEMS) solutions. It became clear that several components were outdated or not functioning, requiring supplementary work, e.g., the rehabilitation of the solar thermal system for hot water and the installation of new cascaded condensation boilers.
Administrative: The project team had to work against a tight deadline despite complex administrative requirements for projects of such scale and technical challenges requiring more upgrades and work. Keeping an open dialogue with the funding agency (Innovation Norway) was essential to stay on track.
Potential for replication & lessons learned
Technological advances are opening new opportunities for the use of geothermal energy, promising to make it an attractive option for cities worldwide. Using geothermal energy to improve energy efficiency and security in the Elderly Home was Alba Iulia's first experience implementing such a complex and large geothermal system in a public building. It will serve as a reference project not only in Alba Iulia but also in the region with several lessons learned:
- When implementing complex energy efficiency projects, expect the unexpected, especially when combining new, state-of-the-art technological solutions with older systems.
- Having thermal response data specific to the area is very helpful when designing the project. If not available, it is highly advisable to do a thermal response test to understand the specific geothermal conditions.
- When implementing geothermal solutions, consider reversible heat pumps for heating and cooling and a higher effort and investment, but covered in the long term by higher efficiency (average co-efficient of performance COP was 4,2/year), especially in colder periods.
- For overall system efficiency, consider combining various solutions managed by BEMS.
- Implementing large and complex projects also involves obtaining relevant permits and preparing different documents as defined in the national legislation, which usually takes considerable time.
- Finally, it cannot be emphasised enough that reliable and experienced designers and subcontractors (for geothermal, electrical, thermal and automation installations) and very good technical supervision are essential for the successful implementation of the project.