Assessing a bio-energy system with carbon capture and storage (BECCS) through dynamic life cycle assessment and land-water-energy nexus
Résumé
Nowadays, much attention is being paid to so-called Negative Emissions Technologies (NETs), designed to remove carbon dioxide from the atmosphere and keep global temperature rise below 1.5 °C. The deployment of NETs can trigger environmental impacts, which can be addressed through the lens of Life Cycle Assessment (LCA). According to the literature, there are several drawbacks when NETs are assessed under the life cycle framework. In this sense, this study aims at contributing to the literature by assessing a NET in a manner that the existing drawbacks are overcome. For such purpose, dynamic LCA and land-water-energy nexus were applied to a Bioenergy with Carbon Capture and Storage system (BECCS). The results show that harnessing residual forest biomass for electricity generation and carbon storage accomplished a great positive climate performance. In line with European climate goals, climate change impact resulted in −2.49E+04 kg CO2eq/MWhe and −3.40E+04 kg CO2eq/t Cstored at year 20. However, the BECCS system analyzed comes at the expense of impacting land, water and energy that cannot be overlooked. The land impact was 3.57E+05Pt/t Cstored and 2.61 E+05Pt/MWhe, green water impact was 11.1 m3/t Cstored and 8.16 m3/MWhe, and the Energy Return on Energy Investment (EROI) was 3.34. The sensitive analysis indicates that special attention should be paid to the efficiency of the system since it directly impacts on land, water and energy (EROI). Finally, this study contributes to increasing the knowledge on NETs, thus supporting climate-energy policymaking.