A turnkey solution for Swedish buildings through integrated PV electricity and battery storage

Abstract

Industry-specific greenhouse gas emission is causing global warming. Energy industries in the EU cumulatively produce 1/4th of the EU’s total greenhouse gas. Considering the net-zero emission target set by the EU, greenhouse gas emission from the energy sector is required to be reduced significantly. As a sustainability leader in the EU, Sweden has already significantly reduced greenhouse gas emissions from energy sectors. However, Sweden needs to contribute more to help achieve EU-level milestones.

The Swedish power system has historically proved its security, reliability, and sustainability. However, lately, Stockholm’s electricity grid proved to be insufficient to handle the increasing electricity need of the city. Increasing the grid capacity is a solution to this problem, but this solution could take years to be implemented properly. Considering Stockholm’s energy crisis, quicker and sustainable energy solutions are required apart from grid capacity expansion.

Considering the net-zero emission target and the Swedish energy crisis small-scale prosumer-based solutions could be a silver bullet. As a renewable energy generation technology Solar photovoltaic has proven its technical and economic feasibility, globally. On the other hand, lithium-ion battery technology is an industry-leading energy storage alternative that could be integrated with solar photovoltaics to solve the associated intermittency with the generation technology.

This study aims to evaluate the techno-economic feasibility of solar photo-voltaic and lithium-ion battery based prosumer models. At the onset, a representative model of the actual solar photovoltaic rooftop system that is installed in the KTH live-in lab was developed to get hourly electricity data. Then, two different prosumer scenarios were developed, and two performance indicators for solar photovoltaic and battery based prosumers were identified and formulated. Furthermore, a linear optimization was performed for the prosumer scenarios, based on the performance indicators and associated constraint equations.

The results of the thesis proved that integrating a battery system with an existing solar photovoltaic installation can increase the techno-economic feasibility of the prosumers. Moreover, battery system size and the amount of available energy significantly affect the prosumer model performance.