The environmental feasibility of algae biodiesel production

摘要

Microalgae can grow in waste or seawater, have vastly superior biomass yields per hectare and, most importantly, the CO2 removed from the atmosphere during photosynthetic growth of the plant offsets CO2 released during fuel combustion. Algae-based fuel products are more promising than first-generation biofuels, as they exclude land use and food security issues, but require a mass production breakthrough to be viable. Through a life cycle approach, we evaluate whether algal biodiesel production can be a viable fuel source once the energy and carbon intensity of the process are managed accordingly. Currently, algae biodiesel production is 2.5 times as energy intensive as conventional diesel. Biodiesel from advanced biomass can only realize its inherent environmental advantages of GHG emissions reduction once every step of the production chain is fully optimized and decarbonized. In the case of Saudi Arabia which operates on a 100 % fossil-based electricity and heat grid, the inherent environmental advantages of producing algae biodiesel would be heavily overshadowed by the nation’s carbon-intensive energy and power sector.