Energilösningar för en energismart stadsdel

Sammanfattning: The aim of this master thesis is to conclude how the energy systems of smart cities can be designed to achieve an annual net-zero energy consumption. The study investigated different techniques that can be used for producing and storing energy locally. This was implemented on a planned residential project located in Veberöd, south of Scania. Hence, the heating and domestic hot water demand were based on the local conditions as well as the computed energy usage of the residential buildings. This was examined through two different scenarios which both aim to create a neighbourhood with net-zero energy usage, while using different techniques and methods. The first scenario consists of geothermal heating combined with heat pumps, photovoltaics panels, and electric heaters. The second scenario consists of borehole thermal energy storage combined with heat pumps and PVT-panels. Furthermore, scenario 2 also includes photovoltaics and solar thermal panels as well as electric heaters. Different simulation tools were used to analyze the behavior and performance of the two scenarios. Earth Energy Designer (EED) was used to design the geothermal systems used for heat supply and storage, including number of boreholes and borehole length. Further, Polysun was used to simulate the complete energy systems, including all the different components for energy production and storage. Based on the designed scenarios in Polysun and EED, an economical evaluation was conducted using the method of life cycle cost as well as pay-back with interest. The result from the study indicated that the residential project can be designed to fulfill the aim of net-zero energy consumption. Furthermore, the economical evaluation indicated a pay-back time of 13 and 32 years, when comparing the two scenarios with district heating which is a common heating source in Sweden. Hence, the conclusions are that several techniques and methods can be used to create residential areas with net-zero energy consumption. However, more optimization of the energy systems is needed to design the smart cities of the future.