Evaluation of household electricity consumption in multi-apartment buildings for optimization of rooftop PV systems

Empowering citizen energy communities (CECs) to produce, self-consume and share renewable energy can enhance household energy efficiency, support the adoption of renewable energy sources, reduce energy consumption and supply tariffs, and increase independence from fossil fuels. This study analyzes actual electricity consumption data from 31 dwellings in typical five-story multi-apartment buildings in Riga, Latvia, considering the potential for rooftop solar energy systems within CECs. The novelty of this study lies in the detailed analysis of household electricity consumption data and characteristics (e.g., household size, population, etc.) to predict household load which is essential for the optimal design of a multi-apartment building scale PV system. We evaluate the suitability of typical multi story buildings for rooftop photovoltaic (PV) systems, aiming to determine the potential PV performance relative to final electricity consumption. The study utilizes PolySun computer simulation software. Our findings indicate that a rooftop PV system on a typical 5 story multi-apartment building (60 apartments) can cover up to 77% of annual electricity consumption. This analysis is based on hourly real electricity consumption data. The research outcomes can inform optimization of on-site energy storage to mitigate the impact of PV systems on the grid. The proposed solution is applicable in many Eastern European countries and in some Western European countries that were influenced by the Soviet Union in the latter half of the 20th century.These regions have a similar stock of panel-constructed multi-apartment residential buildings and share comparable climatic conditions.