The consequence of Carbon Savings (CS) on green energy cost reduction (GECR) using Biogas Logistics Optimization (BGLO) in Tanzania is analysed in this work. The quantitative research approach was adopted with 280 respondents of biogas and energy sector. The results indicate that, the CS has a significant satisfactory impact on GECR and BGLO. Moreover, the cost reduction effect of BGLO is meaningfully mediated, works across CS and cost efficiency. The findings reveal that benefits of environmental sustainability depend not just on the environmental sustainability, but also on the efficiency of logistic systems. The study combines both the SCMT and EET to enunciate the relationships. The results suggest from a practical point of view that the performance of biogas systems could be further enhanced by improving the efficiency of logistics infrastructure and logistics coordination. The study provides valuable policy guidance and insights for future research.