Consumptive life cycle water use of biomass-to-power plants with carbon capture and sequestration

Biomass-to-power conversion provides the most promising route to bioenergy with carbon capture and sequestration (BECCS). The objectives of this study are to estimate the water consumption of biomass-to-power plants with CCS and then quantify its variability and uncertainty on a life cycle basis. The fuel-based life cycle analysis reveals that compared to the case of complete coal combustion with CCS, co-firing biomass at coal-fired power plants with CCS significantly increases the life cycle blue water consumption, depending on the type, co-firing rate, and production location of biomass; and dedicated biomass combustion with CCS further increases the life cycle blue water consumption by a factor of more than 55. Among the numerous stages across both the coal and biomass fuel cycles, the biomass production is the dominant stage accounting for more than 70% of the life cycle blue water consumption for the co-firing path and about 98% for the dedicated biomass-to-power path. These results indicate the importance of advancing agricultural practices and technologies to reduce the overall water consumption. Large-scale BECCS deployment may pose a challenge for water sustainability. Thus, this study calls for a strong need for a close coordination of technology, resource, and policy in transition to a sustainable net-zero carbon energy future.