Decentralized electricity production at household scale, particularly by solar panels, has recently grown due to increased technology feasibility and financial support programs. Further development in this field requires the introduction and efficient use of energy storage technologies. This research aims to evaluate the benefits and economic justification of implementing energy storage systems in private households by using system dynamics modelling. Household electricity consumption is a dynamic problem; therefore, the system dynamics approach allows the development of an exploratory model that accounts for the causal relationships and feedback loops in the system. Specifically, an hourly consumption model is developed to analyze the electricity costs in four scenarios: (1) a standard grid-connected system, (2) a PV system with net metering, (3) a grid-connected system with a connected battery, and (4) a grid-connected system with a combined PV and battery storage system. The structure of the build system dynamics model is described with a Latvian context case. It is found that in Latvian climate-specific conditions, the profitability of installing PV and PV and battery systems in private households in Latvia is justified by both summer and winter conditions. The developed model can be used to analyze the real electricity profiles of specific households, determining the profitability of installing energy-efficient solutions, and is adaptable for analyzing the situations of other countries or accumulation systems.