Examensarbete inom tillämpad termodynamik

Future District Heating Supply in Uddevalla

Master thesis project at the Energy Technology division, Chalmers.

For 1-2 students from Mechanical, Chemical or Chemical Engineering with Engineering Physics.

Main supervisor: Thomas Allguren

Supervisors: Klas Andersson

Examiner: Klas Andersson

Background

The Swedish government has set a target to reach net-zero emissions of greenhouse gases within Sweden by 2045. Drastic changes in the industrial sector are therefore required in the near future. There are several different options being evaluated to reach this target, where different industries have chosen various transition strategies. The energy sector is not an exception. Uddevalla Energi is one example of a local utility company facing the challenges in adapting to the demands of the future. One of Uddevalla Energi’s main responsibilities is to provide heat to the city of Uddevalla via the local district heating network. Uddevalla is located on the west coast of Sweden, about 90 km north of Gothenburg. There are several challenges related to the future supply of district heating networks, including reduced availability of biofuels, stricter climate regulations, increased competition from alternative heating technologies, and the need for greater production flexibility.

Currently, it is the waste fired Lillesjö heat and power plant that provides most of the heat to Uddevalla Energi’s district heating system. During the colder periods of the year, they also use the use the Hovhult plant. The Hovhult plant is an older solid fuel fired system running on biomass. Waste and biomass has for a longe time been an obvious choice for heat generation in Sweden. However, waste streams are changing with respect to composition and are also expected to decrease in the future. At the same time there is an increasing competition for biomass suggest that neither resource will have the same role in the future. The changes foreseen in the energy market also suggest an increased need for production flexibility. Uddevalla Energi is therefore interested in investigating what alternatives are available that could replace the Hovhult plant and at the same time meet future demands.

Suggested master thesis work

The suggested work aims to evaluate a possible replacements for the Hovult plant, that currently acts as main back-up plant in the district heating system of Uddevalla. Two alternatives that Uddevalla Energi is interested in are heat pumps and thermal storage, either as individual solutions or in combination. The work will be a techno economic evaluation of these alternatives. An initial part of the work will be to define the system demand. This will be done by evaluating historical data from the existing plants in the district heating system. Evaluating and defining the system based on this data will be an important part of this work. This evaluation will, together with prediction of market development, act as input to the actual evaluation of the potential in each of the suggested alternatives.

The thesis work will be conducted at the division of Energy Technology, Chalmers. Personnel from Uddevalla Energi will be involved in the supervision and it will also be possible to visit Uddevalla Energi. We seek motivated student/s with an interest in the future of district heating and a suggested background in mechanical or chemical engineering.