Energilagring för ökad egenanvändning av solel i flerbostadshus

• Main Author: Svantesson, Gustaf
• Format: Others
• Language: Swedish
• Published: Uppsala universitet, Fasta tillståndets fysik 2017
• Subjects: energy storage; battery storage; photovoltaics; solar power; self-consumption; energilager; batteri; solenergi; solceller; egenanvändning; Energy Engineering; Energiteknik
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-317252

In this thesis different methods of energy storage are evaluated for use in multifamily residential buildings in order to increase the self-consumption of self-generated photovoltaic electricity. The computational software MATLAB was used to simulate and study five different energy systems applied on two case studies. The five energy systems are; one reference system consisting of photovoltaics, one system with photovoltaics and a hydrogen storage system, and three systems consisting of photovoltaics and batteries using different management strategies. The different systems were compared based on their effect on the buildings self-consumption ratio and grid interaction as well as system costs and profitability. The battery systems successfully increased the self-consumption ratio and decreased grid interaction. Assuming a favourable development of market conditions, all systems containing batteries were paid back. The battery system that could reduce high consumption peaks during the entire year was the most profitable system as the buildings fixed grid fees could be lowered. The hydrogen storage system increased the self-consumption ratio to a small degree, as much of the electricity was lost in the conversion processes. Also, the components of the hydrogen system are very costly and the investment could therefore not be paid back within the 30 year life-time. Photovoltaics can be used to decrease variable electricity costs while energy storage can be used to decrease both variable and fixed electricity costs. The results suggest that focusing on handling power peaks and leveling grid interaction is more valuable than focusing on increasing self-consumption in multifamily residential buildings. The value of energy storage systems in multifamily residential buildings has been discussed with respect to technology development and changes in market conditions, the conclusion being that the value will most likely increase within the next decade and onward. It is believed that local energy storage systems have an important role to play in a power system with an increasing amount of renewable and intermittent power sources.