Malawi’s electricity system is heavily dependent on hydropower, making it vulnerable to climate variability, supply insecurity, and fossil-fuel backup. This study uses OSeMOSYS to assess least-cost and reliable electricity pathways for Malawi from 2022 to 2050 under three scenarios: Business-as-Usual, renewable expansion without storage, and renewable expansion with Battery Energy Storage Systems (BESS). Results show that while the BAU pathway has lower short-term capital requirements, it increases long-term reliability and fuel price risks. Solar PV expansion significantly reduces emissions and system costs, but reliable outcomes are achieved only when supported by adequate storage. The study highlights the importance of a coordinated renewables-plus-storage strategy for improving energy security and enabling a resilient low-carbon transition.