Driftmodellering av saltvattenbatteri för kapning av effekttoppar

There is a power deficit in Uppsala's power grid. Municipal companies have an obligation to contribute with solutions to the power deficit. Skolfastigheter AB have therefore installed an environmentally friendly salt water battery in one of their properties. The goal of this project is to create an algorithm for controlling the battery so that it cuts power peaks at a preschool in Uppsala. The algorithm is created based on economical, environmental, and political aspects. A model of the battery is constructed in which technical specifications for the real battery are used. The model is tested using historical power usage data from one of Skolfastigheter AB's preschool properties. The resulting model successfully cuts the facility's power peaks as intended. The model succeeds even when the input data are varied. The algorithm is also applied in reality and controls the battery via a programmable logic controller (PLC). The goal of cutting power peaks is also met with the PLC. Simulation of the battery cuts power peaks more optimally than when the algorithm is implemented in reality. To improve the model, data from more preschools as well as possibilities to perform more experiments are required. The usage of programmable power storage is today not economically profitable. Batteries do however contribute to reaching Uppsala municipality's environmental and climate goals. Batteries also contribute to a more robust energy system where fossil power reserves can be avoided

Theoretical examination of temperature distribution in an electrical furnace by the study of transient heat conduction effects

The company Kanthal produces electric heating elements that require high temperature treatment in one production step. In this process step, called sintering, the amount of heat received by the sintered material is in direct correlation to the product’s outcome.  It is therefore of interest for the company to gather information about how heat transfer happens in an electrical furnace. This study examines two different possible scenarios of how the heat transfer in the furnace could look like and which amount of heat the sintered material would receive. The relation between a gaseous ambience at a certain temperature and the temperature an object submerged into this ambience is assuming is studied in the process called "transient heat conduction".  Two models were built in Matlab, representing transient heat conduction effects on two different geometries: a plane wall and a short cylinder.  It could be shown that transient heat conduction effects turned out differently for the two models. The conclusion drawn from the results was that the wall model was susceptible to horizontal heat transfer effects, whereas the cylinder model was affected from all directions equally. Further, an analysis of the heat transfer channels within the furnace revealed that the heat leakage through the furnace muffle edges, which are in contact with air, causes a multiple in heat loss compared to the overall heat leakage

Theoretical examination of temperature distribution in an electrical furnace by the study of transient heat conduction effects

The company Kanthal produces electric heating elements that require high temperature treatment in one production step. In this process step, called sintering, the amount of heat received by the sintered material is in direct correlation to the product’s outcome.  It is therefore of interest for the company to gather information about how heat transfer happens in an electrical furnace. This study examines two different possible scenarios of how the heat transfer in the furnace could look like and which amount of heat the sintered material would receive. The relation between a gaseous ambience at a certain temperature and the temperature an object submerged into this ambience is assuming is studied in the process called "transient heat conduction".  Two models were built in Matlab, representing transient heat conduction effects on two different geometries: a plane wall and a short cylinder.  It could be shown that transient heat conduction effects turned out differently for the two models. The conclusion drawn from the results was that the wall model was susceptible to horizontal heat transfer effects, whereas the cylinder model was affected from all directions equally. Further, an analysis of the heat transfer channels within the furnace revealed that the heat leakage through the furnace muffle edges, which are in contact with air, causes a multiple in heat loss compared to the overall heat leakage