Rural energy systems face persistent challenges: low conversion efficiency, sparse renewable energy penetration, and optimization models that prioritize cost at the expense of physical energy quality. A new research framework addresses these limitations through a coupled economic–thermodynamic approach.
The study proposes an AC/DC hybrid architecture with shared energy storage (SES) as the backbone for flexible grid support. The innovation lies in its optimization engine: an exergy economic flow (EEF) model that treats energy not merely as a commodity to be cost-minimized, but as a physical resource with quality metrics tied to economic value. This dual perspective recognizes that wasting high-quality energy incurs hidden economic costs beyond simple purchasing expenses.
The optimization operates in two layers. Long-term decisions—such as storage capacity and equipment sizing—are determined first. Short-term operational strategies then adjust within those constraints across multiple seasonal and demand scenarios. Computational tractability is achieved through linearization and conversion to mixed-integer linear programming (MILP), enabling practical deployment.
Results demonstrate substantial improvements: the integrated approach improved economic performance by 41.9% and energy efficiency by 14.9% compared to economy-focused baseline strategies. This synergy emerges because better thermodynamic efficiency reduces waste, lowering operational costs naturally, while economic discipline prevents over-investment in efficiency upgrades with marginal returns.
The framework holds particular relevance for rural electrification in developing regions, where capital constraints demand intelligent resource allocation. By simultaneously optimizing technical and economic performance, the method provides a decision-support tool for planners balancing renewable integration, storage deployment, and grid stability within realistic budgets. Future work should validate results through pilot implementations and explore adaptation for varying geographic and climatic conditions.
