Mathematical optimization and evaluation of redispatch provision of production processes in a baking factory

To mitigate climate change greenhouse gas emissions need to be reduced immediately. In the energy sector, this can be achieved by replacing fossil fuels with renewable energies. However, this leads to a growing need for redispatch which is associated with increasing costs. Therefore, a method is proposed to involve non-energy- intensive industries in redispatch-provision. In this thesis, the electricity demand of a baking factory was predicted using a physical-based model. As a result, it was found that the cleaning process of two production lines leads to a significant reduction in electricity consumption during the cleaning period. An annual simulation was performed by optimizing weekly production plans based on a mixed-integer-linear programming scheduling formulation. The aim was to find out the cost-optimal times for cleaning between Monday and Friday in two dierent scenarios. In use case 1 cleaning is allowed between 08:00 – 20:00 where as in use case 2 no time limit is defined. Furthermore, a fixed electricity price tari is used in use case 1 and fluctuating day-ahead prices are used in use case 2. The results of the optimization were used to derive redispatch-bids by shifting the cleaning process within the respective day. In both use cases, the optimization led to low energy savings of less than 0.1 %. On the other hand, this means that redispatch can be provided without high eciency losses. Another significant finding was that in use case 1 the optimum timing for cleaning is during lunch time. In use case 2 early morning and afternoon are the most cost-ecient times. 616 and 2142 bids were generated in use case 1 and 2. However, only 104 bids can be accepted by the TSO as the cleaning process can be shifted maximum once a day. The bid evaluation showed, that the bid durations depend on the batch durations and on the time limitations of the cleaning process. Therefore, in use case 2 half of the bids are longer than 5 h 30 min whereas in use case 1 the median is only 2 h 15 min. The bid sizes and bid costs depend on the time of the year as the outside temperature influences the energy eciency ratio of the refrigeration system. Typical bids range between 170 kW and 310 kW where as bid costs can be expected between 5 € and 170 €. It can be concluded that the analyzed industrial operator could provide redispatch-bids. However, there is no market for industrial redispatch-provision yet. Therefore, incentives and regulations need to be developed to lower entry hurdles.