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    The Potential of Flexible Heating for Multi-Family Houses in Sweden
    (2024) Kleinschmidt, Per; Söderlind, Ida; Chalmers tekniska högskola / Institutionen för rymd-, geo- och miljövetenskap; Chalmers University of Technology / Department of Space, Earth and Environment; Göransson, Lisa; Bertilsson, Joel; Persson, Mari-Louise
    The residential and services sector accounted for a significant portion (39%) of the final energy consumption in 2020 in Sweden, with district heating (DH) and elec tricity as the main heating sources. The choice of heating source varies throughout different types of buildings, and the most common for multi-family houses in Sweden is DH. When moving towards an energy system with a larger share of renewables, which includes irregularity of production, a flexible demand of electricity will be important to maintain the balance between production and consumption in the power system. This thesis aims to investigate the potential of flexible heating for multi-family houses in Sweden. The investigation has been made by a model structured in GAMS by using mixed-integer linear programming, to optimize the heating pattern and the installed capacity, with the aim of minimizing the total annual cost (including in vestment, operational, and maintenance costs). The robustness of the model and results have been assessed by adjusting the input data, such as the district heating power and energy price, the electricity grid price, and the heat pump (HP) lifetime. The scope of the thesis was to investigate the potential of flexible heating in dif ferent regions of Sweden. Luleå, Sundsvall, Gothenburg, and Malmö have been investigated due to their geographical location as they are located in different elec tricity zones. The study focused on two buildings built in different eras. This comparison aimed to highlight the differences in results based on the different building characteristics. The thesis is in collaboration together with Riksbyggen (Swedish housing company), which provided the data for the buildings involved in the study. The results indicate that flexible heating in multi-family houses in Sweden is econom ical favorable. A wider accepted indoor temperature range (19°C - 25°C) decreases the total heating demand, the necessary installed capacity and the total cost up to 14% compared with a non-flexible indoor temperature range (21°C - 22°C). The most economical favorable heating technology when implementing flexible heating is the heat pump, to make use of the thermal inertia and heating pattern in the most cost-effective way.
  • Post
    Implementation of Dry Hydrated Potassium Carbonate Carbon Capture
    (2024) Jacobson, Kajsa; Törnqvist, Frida; Chalmers tekniska högskola / Institutionen för rymd-, geo- och miljövetenskap; Chalmers University of Technology / Department of Space, Earth and Environment; Rydén, Magnus; Stanicic, Ivana; Stenström, Oscar
    In near future, Waste-to-Energy (WtE) plants are required to reduce their CO2 emissions drastically in order to achieve carbon neutrality. Since energy recovery from waste likely will persist, a necessary mitigation strategy is to implement a Carbon Capture and Storage (CCS) technology on site. In contrast to conventional methods, Dry Hydrated Potassium Carbonate (DHPC) carbon capture can provide low energy penalty, easy regeneration and opportunities to integrate the excess heat in the District Heating (DH) system. The DHPC process is based on solid absorp tion and performed by circulating a sorbent, potassium carbonate, K2CO3, between two fluidized bed reactors. This thesis performs a case study which implements the DHPC process at Renova’s WtE plant in Sävenäs. The application of the DHPC carbon capture is investigated by modeling the WtE and the DHPC process, using the simulation tools Ebsilon and Aspen Plus, re spectively. When modeling the capture process according to the design proposed in research, an alternative design of the regeneration reactor is discovered able to reduce its steam demand, the fluidized bed heat exchanger (FBHE). The FBHE configuration as well as the original design of the DHPC process, lay the foundation for the construction of multiple system cases to analyse throughout the project. The potential for heat integration, in the different cases, is evaluated by performing a pinch analysis which creates the basis for retrofitting the WtE plant. In addition, the energy performance, reactor sizes and capture cost are investigated. The thesis reveals that the DHPC process is a promising CCS method for Renova, especially the case using a FBHE. In particular, integrating this capture process increases the delivery of DH by 2.27-3.29% while reducing the electricity production by 2.09-8.51%, depending on the pressure level of the utilized steam. As a result, the total energy efficiency of the WtE plant is expected to increase by 1.47-1.57%, after applying the FBHE DHPC processes. In addition, the economic evaluation indicates on low capture costs including operational costs which are relatively in sensitive in terms of future energy prices. In conclusion, it is recommended for Renova to investigate the DHPC process fur ther, since by choosing this method, the WtE plant can almost maintain its normal production of electricity and DH. However, in order to enable a future implementa tion of the process, it is of importance to verify the function of the FBHE reactor and evaluate the physical footprint of the system in the light of the found reactor sizes as well as the practical feasibility of the proposed retrofits.
  • Post
    Technoeconomic Analysis of Storing Industrial Waste Heat in a Novel Heat Storage
    (2024) Javaherneshan, Dorin; Chalmers tekniska högskola / Institutionen för rymd-, geo- och miljövetenskap; Chalmers University of Technology / Department of Space, Earth and Environment; Harvey, Simon; Laukkanen, Timo
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    Emission pathways for information and communication technologies
    (2024) Wartenberg, Sofia; Chalmers tekniska högskola / Institutionen för rymd-, geo- och miljövetenskap; Chalmers University of Technology / Department of Space, Earth and Environment; Johansson, Daniel; Morfeldt, Johannes
  • Post
    The Dynamical State of a Massive Infrared Dark Cloud Filament
    Larsson, Carl; Chalmers tekniska högskola / Institutionen för rymd-, geo- och miljövetenskap; Chalmers University of Technology / Department of Space, Earth and Environment; Tan, Jonathan; Law, Chi-Yan