Ekonomiska och tekniska möjligheter med batterilager : En lönsamhetsstudie av batterilager i solcellsförsedda kontorsbyggnader

Sammanfattning: The ability to store energy becomes even more important as the proportion of intermittent and local energy production increases. The growing electric car industry is dependent on batteries and because of this, battery storage technologies are emerging rapidly. This project analyses how a real estate company can take advantages of a battery storage installed in office buildings equipped with a photovoltaic system. The results are based on simulations on two test facilities where three saving opportunities were analysed. These opportunities are; peak shaving, transfer charge and store surplus from the photovoltaic system. A local battery storage combined with a smart control software can facilitate an opportunity for actors to capitalize on the varying electricity prices. This study shows that one of the main issues with battery storage is how to formulate a strategy around charge and discharge of the battery. The challenge is to find a balance between having enough energy stored to enable peak shaving and to be prepared to store potential surplus energy. The electricity surplus is generally higher during weekends due to less activity in office buildings, which means that a battery storage with higher capacity is required during weekends in comparison to workdays. This study’s net present value calculation over the time of 15 years, with a 5 % discount rate and assumed 3 % increase of electricity price and peak cost, indicates that the investment cost of a battery storage needs to decrease by 50 % to become financially sustainable.