The PersonAI project focuses on groundbreaking innovations in user-centric energy services within the building sector, leveraging AI. Initial analyses predict energy savings of 22% to 44% and comfort enhancements of 22% to 86% through AI-driven energy services and Personal Comfort Models. Central to the project is the fusion of these technologies, pursued through an extensive long-term study involving 40-50 participants for detailed data collection (including surveys, skin temperature, heart rate, etc.) across a diverse population sample. The resulting Personal Comfort Models will be integrated and showcased in an energy service, demonstrating the concept in collaboration with key stakeholders.