This study uses a hybrid Life Cycle Assessment approach to evaluate the environmental impacts of large-scale deployment of Carbon dioxide Capture and Storage (CCS) in coal and natural gas based electricity generation, based on IEA scenarios. For the Baseline scenario, all impact categories would increase 2-3-fold in 2050 from 2005 levels. Green House Gas (GHG) emissions are found to decrease by similar to 40% in ACTmap scenario and by similar to 75% in more CCS-intensive BLUEmap scenario. These climate mitigation scenarios also show significantly reduced impacts of acidification, particulate matter formation and human toxicity, suggesting the existence of co-benefits. For eutrophication, all scenarios indicate substantial increases, but the increases are largest in the Baseline scenario. For photochemical oxidant formation, only the mitigation scenarios manage to stabilize this impact from fossil fuel based power production. This study does not assess the impact of alternative power generation or energy efficiency technology that replaces part of the fossil fuel power in the mitigation scenarios. (C) 2012 Elsevier Ltd. All rights reserved.