Sector coupling in an urban development on a city district level

Abstract

The concept of sector coupling has garnered attention over the last few years as an important component in the energy transition. Particularly, the term holds growing interest given the benefits it delivers in energy systems, providing flexibility and higher integration of renewable energy sources in an environment where the stability of the grid is increasingly volatile. This holds pertinence in the development of urban landscapes given the high energy requirements of such areas. As such, this Master’s thesis aims to gain an understanding of the viability and impact of sector coupling in urban developments on a city district level, investigating the integration of generation and storage assets in the energy system of Ulleråker. The city district in the Södra Staden project is part of the expansion of southern Uppsala and is chosen as the study area due to its primarily domestic and commercial profile, providing insights into the development of future residential areas. Additionally, the ongoing construction activities in Ulleråker and Uppsala kommun's commitment to climate-neutrality objectives make it a practical and relevant case study for examining sector coupling and its implications. To assess the potential for sector coupling in the development of Ulleråker, a comprehensive methodology is employed in this study. Initially, a thematic analysis using NVivo software is conducted to identify the relevant elements of sector coupling based on previous research. This analysis helps in determining the key features and characteristics of sector coupling that are most pertinent to the case study. Subsequently, available schematics of the program area, consulting reports, and interviews with both Uppsala kommun and Vattenfall are utilized to perform a thorough analysis of the program area. EnergyPLAN is ultimately selected as the modelling tool due to its holistic approach to energy systems modelling and ability to provide output at an hourly resolution. The model's built-in distribution library is also used in conjunction with annual demand measurements to project demand profiles for Ulleråker, facilitating a comprehensive assessment of sector coupling opportunities in the area. The energy system design is optimized based on technical and market-economic considerations relative to a base case. The implementation of sector coupling applications in the city district study yields notable outcomes. Carbon intensity is reduced by an average of 41.33% through the substitution of boiler plants with heat pumps, leading to a less carbon-intensive system. The annual heating supply remains consistent at approximately 41.2 GWh, while the electricity supply increases from 13.5 GWh to an average of 20.1 GWh in both simulations due to a more diverse supply profile and additional demands from heat generation and storage assets. The technical simulation results in a more energy-independent system with a 62.88% decrease in import from the main grid, while the market simulation relies more on grid import with an 18.33% increase. The cost analysis shows similar costs for both simulations, averaging 118,763 MSEK, representing a 14% increase compared to the base case without sector coupling technologies. Based on simulations, it is also deemed that simplifications in EnergyPLAN limit the detailed assessment of heat production and storage, potentially affecting the accuracy of the results and indicating a significant limitation of the modelling tool. Future work should address the limitations of the current study and explore the potential of sector coupling on larger scales, enabling a more integrated and comprehensive approach to energy system design and management