The road to achieving the long-term Paris targets: energy transition and the role of direct air capture

Abstract

In this paper, we quantify the energy transition and economic consequences of the long-term targets from the Paris agreement, with a particular focus on the targets of limiting global warming by the end of the century to 2 and 1.5 °C. The study assumes early actions and quantifies the market penetration of low carbon technologies, the emission pathways and the economic costs for an efficient reduction of greenhouse gas (GHG) emissions such that the temperature limit is not exceeded. We evaluate the potential role of direct air capture (DAC) and its impact on policy costs and energy consumption. DAC is a technology that removes emissions directly from the atmosphere contributing to negative carbon emissions. We find that, with our modelling assumptions, limiting global temperature to 1.5 °C is only possible when using DAC. Our results show that the DAC technology can play an important role in realising deep decarbonisation goals and in the reduction of regional and global mitigation costs with stringent targets. DAC acts a substitute to Bio-Energy with Carbon Capture and Storage (BECCS) in the stringent scenarios. For this analysis, we use the model MERGE-ETL, a technology-rich integrated assessment model with endogenous learning.

Negative emissions—Part 2: Costs, potentials and side effects

“…Importantly, the vast majority of mitigation scenarios considered here only features negative emissions via bioenergy with carbon capture and storage (BECCS). We interpret this evidence as a lower-bound estimate of negative emission potentials in these models, since the introduction of additional NETs seems to consistently increase cumulative NETs deployment (Chen and Tavoni 2013, Humpenöder et al 2014, Marcucci et al 2017.…”

“…While the vast majority of studies feature BECCS as the only explicit NET in the portfolio, a number of studies examine the role other NETs, often in small portfolios of two NETs that include BECCS. These studies looked at afforestation and reforestation (AR) (Humpenöder et al 2014, Kreidenweis et al 2016, Tavoni et al 2007, Edmonds et al 2013, Reilly et al 2012, Popp et al 2017, Rose et al 2012, Calvin et al 2014, enhanced weathering (EW) and direct air carbon capture and storage (DACCS) (Marcucci et al 2017, Chen and Tavoni 2013, Strefler et al 2018b. The IAM community is currently investigating the role of larger NETs portfolios including AR, BECCS, DACCS and EW.…”

“…Chen and Tavoni (2013), Marcucci et al (2017) and Strefler et al (2018b) provide the only assessments of DACCS in a full-fledged integrated assessment model. They find that DACCS may only be profitable for very stringent climate policies.…”

“…As in the two companion papers to this piece (Nemet et al 2018, Minx et al 2018, our review is 12 Although the term storage might imply accumulation for future use, we use it here interchangeably with the term 'sequestration' in accordance with the literature reviewed. 13 Notable exceptions are Marcucci et al (2017), Chen and Tavoni (2013) and Strefler et al (2018b) for DACCS and Strefler et al (2018a) for terrestrial enhanced weathering. Strefler et al (2018b) combined three NETs (AR, BECCS and DACCS) for the first time.…”

Negative emissions—Part 1: Research landscape and synthesis

“…At the same time, modelling teams have started with the implementation of larger portfolios of NET options beyond BECCS (e.g. Chen and Tavoni 2013, Marcucci et al 2017, Streffler et al 2018. This could lead to even larger cumulative carbon dioxide removal in upcoming mitigation scenarios, as suggested by these initial studies.…”