In Latvia, achieving an 80 % self-consumption rate is a key requirement for electricity prosumers to access renewable energy support schemes. However, individual photovoltaic systems often fail to meet this threshold due to a mismatch between electricity generation and consumption patterns. This paper examines how self-consumption rates influence the economic justification for establishing energy communities. Results show that mixed-source setups, such as integrating diverse consumer types (e.g., residential, educational and commercial), and, by combining electricity prosumers and consumers, it significantly enhances energy communities selfconsumption rate. The paper explores their economic feasibility under Latvia's net billing system, assessing key financial indicators like net present value, payback period and internal rate of return. The findings provide recommendations for Latvia's energy transition, emphasising the integration of renewable energy sources and supportive regulatory frameworks to increase self-consumption rate and promote sustainable energy communities.