The City of Aachen's website has services such as the the city of Aachen has valuable opportunities for citizens to citizens to participate in shaping the city or to voice their concerns. their concerns. In order to be able to process such feedback from citizens means, it makes sense for citizens to look for the responsible office and submit their concerns or feedback there. LLMs (Large Language Models) offer the opportunity to make the city's make the city's services easier for citizens to find. Some services are already included in the knowledge base of publicly accessible LLMs such as ChatGPT (e.g. the 4o model). For example, the input that something is growing in the cycle path in Aachen leads to a response that links directly to the defect report. Native integration on the website can make the city's services city's services even easier to find.

Buildings and cities are getting more digitized, but are they equally getting smarter?  According to the World Energy Outlook Report from 2024 , the building sector is responsible for 37 % of the world's electricity consumption, with an upward trend for the future. A significant hurdle to building operation optimization is the lack of structured and clearly labeled data (Saloux et al. 2023 ). The increased use of monitoring devices is encouraging the digitization of buildings and city neighborhoods. However, the recorded data usually accumulates in unstructured and unprocessed ways, i.e., in data lakes. Yet, to make the most of the recorded data and be able to analyze it as well as optimize the actual building energy system, there needs to be structure, i.e., data warehouses. Better yet, structured data should have an accompanying context so that from the information, we get knowledge and can extract patterns and relationships about building operations. Using FIWARE, an open-source platforming solution for smart cities, a network of context-aware data warehouses for building energy systems could be curated for the city of Aachen. While incorporating regulations for data privacy and security, e.g. GDPR framework and the NIS2 directive , anonymized statistics and patterns could be shared across buildings to leverage the knowledge and fill the gaps in individual buildings. For example, an incident of faulty operation identified in one building could be used to prevent or subdue the effects of similar incidents in other buildings. Or a successful measure for energy efficiency undertaken in one building could be adapted in other buildings of a similar profile after the benefits have been proven and any side effects studied.

vaestro offers landlords and owners of apartment buildings an innovative way to replace outdated heating systems without extensive renovations. Our solution uses Scandinavian technology to electrify the heating supply of each apartment individually. In addition, vaestro provides landlords with a business model that incentivizes them to proactively replace heating systems, promoting a seamless transition to this future-proof technology.