# Strategic Resource Planning for Sustainable Biogas Integration in Hybrid Renewable Energy Systems
They examined stages such as feedstock management, anaerobic digestion, and combined heat and power integration, noting that regional factors significantly influence environmental impacts. The study emphasizes that while manure-based biogas production has global potential, regional adaptations are necessary to maximize sustainability outcomes. Furthermore, ref. [18] analyzed the technical challenges facing biogas plants in agriculture-heavy countries like Pakistan, noting that sector growth still needs improve ment despite the substantial organic waste available for biogas production. Key issues include inadequate infrastructure, gas leakages, digestate management, and corrosion, which affect the sustainability and efficiency of biogas operations. The authors recommend design improvements, such as leak-proof piping, optimized digestate removal, corrosion-resistant materials, and government support, as essential for realizing biogas's potential as a reliable renewable energy source in Pakistan and similar regions. Additionally, ref. [22] optimized biogas production through co-digestion of canola residues and cattle manure, using the response surface methodology to enhance methane yield. Key factors--temperature, total solids concentration, stirring time, and inoculum ratio--were identified as crucial for biogas productivity. In different lab experiments, thermophilic conditions produced the highest methane yield, generating 403.63 1/kg of organic material. The study highlights the response surface methodology as an effective tool for optimizing anaerobic digestion parameters. It demonstrates that co-digestion under controlled conditions significantly boosts methane production, making it advantageous for renewable energy applications. Despite these advancements, a common shortcoming remains the need for further integration of logistical challenges within a holistic system. While these studies advance the technological aspects of biogas production, they often need to fully address practical issues related to biomass sourcing, transportation, and storage. Handling perishable and bulky materials like manure presents significant difficulties that can affect the feasibility and sustainability of biogas projects. Many rely on simulations or controlled conditions without incorporating actual data, failing to account for the complexities of biomass logistics. Recognizing these gaps, some research has focused on biomass logistics and supply chain optimization [26; 27; 28; 29; 30; 31]. These studies address crucial operations such as harvesting, storage, pre-processing, and transportation, highlighting that logistics can account for a significant portion of biomass supply costs. For instance, ref. [27] developed a multi-objective optimization model for designing a sustainable biomass supply chain network, focusing on poultry waste. Their model integrates geographic information systems and the analytic hierarchy process to identify suitable biogas facility locations. The model demonstrates significant cost-effectiveness and environmental benefits by balancing profit maximization with minimizing transportation distances. Similarly, ref. [28] developed a regional optimization model for biomass transportation, considering economic, social, and environmental costs. Using a mixed integer linear programming framework, they evaluated sustainable transportation costs for potential bioenergy plant locations, incorporating region-specific data on emissions, pavement damage, and traffic congestion. Their findings emphasize the importance of multimodal transport options (truck and rail) to reduce emissions and cost, highlighting the need for comprehensive cost evaluations to support sustainable biomass logistics. Moreover, ref. [30] comprehensively reviewed biomass transportation and logistics, emphasizing its critical role in the bioenergy supply chain. They categorized research findings across multiple criteria, including logistics cost, transport distance, plant capacity, and system efficiency.