Limiting climate change to 2°C with a high probability requires reducing cumulative emissions to about 1600 GtCO 2 over the 2000-2100 period. This requires unprecedented rates of decarbonization even in the short-run. The availability of the option of net negative emissions, such as bio-energy with carbon capture and storage (BECCS) or reforestation/ afforestation, allows to delay some of these emission reductions. In the paper, we assess the demand and potential for negative emissions in particular from BECCS. Both stylized calculations and model runs show that without the possibility of negative emissions, pathways meeting the 2°C target with high probability need almost immediate emission reductions or simply become infeasible. The potential for negative emissions is uncertain. We show that negative emissions from BECCS are probably limited to around 0 to 10 GtCO 2 /year in 2050 and 0 to 20 GtCO 2 /year in 2100. Estimates on the potential of afforestation options are in the order of 0-4 GtCO 2 /year. Given the importance and the uncertainty concerning BECCS, we stress the importance of near-term assessments of its availability as today's decisions has important consequences for climate change mitigation in the long run.

Carbon Capture and Storage (CCS) can be a valuable CO 2 mitigation option, but what role CCS will play in the future is uncertain. In this paper we analyze the results of different integrated assessment models (IAMs) taking part in the 27th round of the Energy Modeling Forum (EMF) with respect to the role of CCS in long term mitigation scenarios. Specifically we look into the use of CCS as a function of time, mitigation targets, availability of renewables and its use with different fuels. Furthermore, we explore the possibility to relate model results to general and CCS specific model assumptions. The results show a wide range of cumulative capture in the 2010-2100 period (600-3050 GtCO 2), but the fact that no model projects less than 600 GtCO 2 indicates that CCS is considered to be important by all these models. Interestingly, CCS storage rates are often projected to be still increasing in the second half of this century. Depending on the scenario, at least six out of eight, up to all models show higher storage rates in 2100 than in 2050. CCS shares in cumulative primary energy use are in most models increasing with the stringency of the target or under conservative availability of renewables. The strong variations of CCS deployment projection rates could not be related to the reported differences in the assumptions of the models by means of a cross-model comparison in this sample. 1 Introduction CCS is often mentioned as a key response option to mitigate greenhouse gas emissions (Fisher et al. 2007). The technology can be used to reduce emissions from power plants, hydrogen

Projections of the deployment of Carbon Capture and Storage (CCS) technologies vary considerably. Cumulative emission reductions by CCS until 2100 vary in the majority of projections of the IPCC-TAR scenarios from 220 to 2200 GtCO 2. This variation is a result of uncertainty in key determinants of the baselines of different models, such as, technological development (IPCC Special Report on Carbon Dioxide Capture and Storage. Prepared by Working Group III of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, United Kingdom and New York). Technological key parameters of CCS deployment are power plant efficiency and investment cost, capture cost, transport cost and storage capacity. This study provides insights in how uncertain the key parameters are and how this influences CCS deployment projections. For each parameter, ranges are determined on the basis of the existing literature. CCS deployment is systematically assessed for all of these parameter ranges in a global energy system model (TIMER). The results show that investment cost uncertainty causes the largest range in cumulative CO 2 captured from global electricity production (13-176 GtCO 2 in 2050) in a scenario with a medium fossil fuel price level. The smallest, but still significant range of 65-91 GtCO 2 cumulatively captured until 2050, is caused by the uncertainty in the efficiency of the power plant and capture unit.

h i g h l i g h t sWe compare GHG mitigation policy including or excluding CCS on socio-economic impacts for the Netherlands. We simulate these policy options in a global multiregional Input-Output Model with detailed bottom-up technology data. Economy-wide differentials between these mitigation policies are small for Employment, GDP and Imports. Notable impacts are found for the energy sector and some upstream sectors (natural gas, construction). This pattern shows to base a choice on macroeconomic impacts is hard and it will affect strong and vested interests. a b s t r a c tCarbon Capture and Storage (CCS) could be an interesting option to mitigate greenhouse gas emissions in the Netherlands. This study compares a mitigation strategy for the Dutch power sector that includes CCS to one without on several socio-economic indicators. In particular, we calculate incremental gross value added (GVA), employment and import dependency impacts of two such low-carbon power production portfolios for the Netherlands. We combine technology specific techno-economic bottom-up data with a macro-economic multi-regional Input-Output-Table containing high sectoral detail. For the total economy, we find the differences between these scenarios to be small. Still, gross value added, and employment are lower under the CCS-inclusive strategy, while import dependency is higher. For the power sector, the differences between the scenarios are, however, considerable. Furthermore, our analysis shows that also for other sectors the differences between the scenarios could be large. For instance, a CCS-exclusive strategy leads to considerably higher GVA and employment in domestic construction services, while the CCS-inclusive strategy comes with considerably higher GVA and employment for natural gas mining and related upstream sectors.

a b s t r a c tCarbon capture and storage (CCS) is a potential key-technology to mitigate greenhouse gas (GHG) emissions as its use can lead to lower mitigation cost. However, research on other economic impacts of using CCS is scarce. In this paper, we look into economic upstream impacts of CCS use in terms of employment, Gross Value Added (GVA) and import dependency on the macro-and sector-level in Western Europe. We determine these impacts by a static comparison of two scenarios of power production with and without CCS (differences in energy efficiency investments between these scenarios were not accounted for). The two scenarios, both representing a stringent climate policy regime, were produced with the energy-system-simulation-model (TIMER) following the same emission profile until 2050. Data from the two scenarios were respectively implemented into a projected version of a global-multiregional IO-Model (EXIOBASE). Macro-level results suggest slightly higher gross employment, but lower Gross Value Added (GVA) (by 25%), and higher import dependency in the CCS-including scenario compared to the CCS-excluding scenario, given that biomass with CCS (BECCS) is available. Sector-level results show disproportionally higher differences between the scenarios in GVA and employment for some sectors compared to other sectors. Particularly, sectors providing fuels (here mostly bio-energy) have significantly higher GVA and employment in the CCS scenario. This study thus reveals interesting upstream economic effects, which can be linked to the technology choice. However, the exact quantitative results depend strongly on model assumptions. Results therefore need to be further explored in other models.