In recent years, the rapid increase in energy demand and the threat of climate change have pushed the energy sector towards electrification. Despite this being the first step to a more sustainable future, a new problem arises with the growing demand: grid congestion. This project explores innovative strategies within energy system design and operational framework to enhance operation efficiency in large urban energy systems. A model was established that allows the optimization and analysis of the performance of a residential energy community with energy systems supplied by renewable sources. The design focuses on the flexibility of the system to operate with an integrated planning framework exploiting batteries, thermal storage and shared Electric Vehicles (EVs). By investigating these technologies' design and operational conditions, the project seeks to optimize the system's functioning and minimize its impact on the electricity grid to mitigate congestion. Focusing on a new residential area in Utrecht (NL), the study investigates the role of flexibility for new capacity connection challenges in a highly populated urban area with a vulnerable infrastructure. This research provides useful insights that can guide the development of more adaptable energy infrastructures capable of meeting the growing demands of modern cities. The findings aim to inform future urban energy areas to facilitate the transition towards a more sustainable residential landscape.