This research explores the multifaceted impacts of biochar, a cost-effective material widely used for environmental applications, specifically in chromium-contaminated wastewater remediation. Utilizing an adapted 3E model (EA-EC-ER), the study quantitatively assesses three critical units of biochar—environmental application (EA), energy consumption (EC), and environmental risk (ER). The biochar, produced from three biomasses at different temperatures, demonstrates a positive correlation between EC and biochar yield. Notably, low-temperature biochar exhibits superior chromium removal performance.

Ulva prolifera biochar, produced at 500°C, emerges with the highest recommendation index due to low EC, high EA, and reduced ER. The study establishes a rapid assessment methodology, extracting parameters to recommend the top eight percent of biochar from collected peer-related data. Addressing the complexities of biochar production in the context of circular bioeconomy, the research emphasizes the need for communal investigation into the interplay of EC, EA, and ER. The study underscores the importance of considering the environmental impact of each unit to ensure biochar’s effective contribution to sustainable development goals. Notably, the findings provide comprehensive guidance for selecting biochar types based on their multiple impacts, shedding light on the intricate balance required for global sustainability.