VIREAS: An AI-powered virtual energy assistant supporting Europe’s energy transition 

Despite the availability of financial incentives and increasingly accessible technologies, many citizens still face significant obstacles when starting energy renovation projects. The complexity of technical, administrative, and legal information often leaves homeowners uncertain about eligibility for support, technical requirements, and the steps needed to carry out renovation measures.  

Recognising these challenges and the growing demand for clear, reliable, and user-friendly information, the Regional Energy Agency North (REA North) developed VIREAS, a virtual energy assistant created within the EU Interreg Euro-MED project BauNOW. 

An accessible virtual energy assistant 

VIREAS provides citizens with personalised, comprehensible, and trustworthy guidance when planning energy renovation measures or investing in renewable energy technologies for their homes. Accessible at vireas.rea-sjever.hr without installation and adapted for both computers and mobile devices, the assistant offers an intuitive, conversational interface that helps users navigate the often complex renovation journey. 

The tool is built on a structured knowledge base drawing from official regulations, technical guidelines in construction, energy and renewables, current funding criteria, and documentation used by experts and consultants. Insights gathered through interactions with a pilot group of citizens were also integrated. While relying on advanced AI capabilities, VIREAS does not replace qualified professionals; instead, it provides initial orientation before users seek formal technical or legal advice. 

Interactive and user-oriented features 

Unlike static online guides, VIREAS enables two-way communication in everyday language. At this stage, it provides guidance exclusively in Croatian, with multilingual expansion planned for future development phases. After a simple registration process requiring only the user’s domicile county and email address, citizens can ask specific questions, receive detailed answers based on verified sources, and continue the conversation with further clarifications. Conversations can be exported in PDF format, and basic usage statistics are available within the user profile. Typical queries include how to start renovating a house, understanding ETICS facades (External Thermal Insulation Composite System) and their costs, or applying for a public support scheme for solar PV installation. 

A robust AI-based approach 

VIREAS was developed through collaboration between an external expert specialised in large language model (LLM) solutions and the engineering team of REA North. The agency led the collection and structuring of regulatory, technical, and funding documents, which were transformed into a vector-based knowledge database and integrated with the Gemini 2.5 Flash language model. Multiple prototypes were tested by the staff and a pilot group of citizens, allowing response accuracy and reliability to be continuously refined prior to public deployment.  

Scaling up at local level 

VIREAS is designed as a scalable solution that REA North will continue to maintain and further develop beyond the project’s lifetime. Future versions will be adapted to local and regional contexts, enabling citizens to access guidance that reflects locally applicable rules, incentives, and funding schemes.  

By simplifying access to complex information and empowering citizens to make informed decisions, VIREAS contributes to accelerating the energy transition of Europe’s building stock. 

This best practice is extracted from our publication ‘Sustainable Regions in Action‘. Discover more best practices here!