Assessing the Environmental Impacts of the Black Soldier Fly-Based Circular Economy and Decentralized System in Singapore: A Case Study

Food waste management is a major global issue, and alternative protein sources like insect farming offer a sustainable solution. This study investigated the environmental impacts of black soldier fly larvae (BSFL) production using a Life Cycle Assessment (LCA), evaluating its role in both protein production and food waste treatment. The assessment considered three functional units: FU₁ (1 kg of dried larvae), FU₂ (per kg of protein), and FU₃ (treatment of 1 ton of food waste). The results indicate that larvae rearing is the largest contributor to emissions in FU₁ (46% of 18.51 kg CO₂ eq). In FU₂, BSFL protein shows a higher climate impact (49.41 kg CO₂ eq) than fishmeal or soybean meal but requires significantly less land. FU₃ demonstrates that BSFL-based composting can achieve net negative emissions (~−24.8 kg CO₂ eq), outperforming conventional waste treatment. An optimized scenario (Scenario A) shows marked improvements across all units compared to a Business-as-Usual case, including a 79% reduction in FU₁ emissions and a 577% increase in FU₃ carbon savings. These findings underline the environmental advantages of BSFL systems, especially in Singapore, and support their potential as sustainable alternatives for protein production and food waste management.