Abstract

This master’s thesis investigates the optimal sizing of a battery storage system to ensure electricity efficiency, while considering cost-effectiveness, utilization rate and sustainability regarding carbon dioxide emissions. The study is a case study for the Swedish nuclear fuel and waste management (SKB), whose mission is to manage the radioactive waste. A total of four scenarios were designed, each with a different dimension of battery storage systems, and were simulated to see the usage during the years 2027 to 2038.

The finding indicates that the best alternative for SKB to secure electricity efficiency is Scenario 2 with a battery of an energy capacity of 20 MWh and a maximum capacity of 5 MW. This scenario is the second most cost-efficient, has the second-best utilization rate and is third overall in reducing carbon dioxide emissions. If SKB wants to take all these aspects into consideration, then Scenario 2 is the best option. To get the best use out of the battery the recommendation is to implement the battery storage system around 2032 due to the trajected higher power consumption. If SKB would be granted more power from the power grid, there would be a decrease in cost and carbon dioxide emissions. If 10 MW were granted, both the cost and carbon dioxide emissions for Scenario 3 would be lower than covering everything with diesel. If 12 MW were granted the battery storage system would be enough to cover all power use for three out of four scenarios. Scenario 3, with the lowest battery dimension, is the only scenario that still needs conventional diesel to cover the power use when given 12 MW.