The future development of district heating in Gothenburg
Examensarbete för masterexamen
Sustainable energy systems (MPSES), MSc
Göteborg Energi is the sole provider of district heat in the Gothenburg region in Sweden. By the year 2030, the generation of heat in Gothenburg is planned to be free of fossil fuels. The plans include the construction of a biomass-fuelled combined heat and power plant and an increased use of bio gas. These plans are already set, but there are many possible additional measures that could be implemented in the district heating system that will help to meet the targets set for 2030. However, the future is hard to predict and it may be difficult to choose which measures to implement. In order to assess the possible measures to be implemented, an optimisation study through the software GAMS has been performed in this thesis: a model of the generation of district heating in Gothenburg has been created and 4 different scenarios where measures to decrease total system running costs have been implemented by the year 2032 have been studied. These measures are: seasonal thermal energy storage, thermal energy storage in buildings, thermal energy storage in a hot water accumulator tank and an increased use of exhaust air heat pumps in buildings. The district heating system is affected by the electric system in several ways through the price of electricity. In the future, when more electricity is generated from intermittent sources such as wind or solar, the price of electricity will be fluctuating and the district heating system must be able to handle these fluctuations. The optimisation is performed on an hourly basis and includes hourly prices for electricity that have been previously simulated for 2032. It was found that it is possible to achieve a fossil-free generation of heat in Gothenburg by 2032. The studied measures all give system cost savings in the form of reduced running costs. By introducing thermal energy storage in the district heating system, substantial savings in running costs can be achieved, as well as reduced heat load variations on both daily and seasonal levels. By using buildings as thermal energy storage, similar cost savings as for an accumulator tank can be achieved, but at much lower investment cost. A seasonal thermal energy storage will give large cost savings and heavily reduced heat load variations, but at a very high investment cost. With an increased amount of exhaust air heat pumps in buildings, the total running costs of the heat generation system can be reduced. However, these heat pumps will give a small increase in heat load variation on a system level.
Building Futures , Energi , Hållbar utveckling , Samhällsbyggnadsteknik , Building Futures , Energy , Sustainable Development , Civil Engineering