Non-CO2 abatement: New dataset on costs and new representation in economic models

To construct emission pathways for deep mitigation futures, considering non-CO₂ emissions and mitigation is important to allow for a full range of abatement options, including relatively cheap ones. However, the more the world moves towards net zero emissions, the more important some remaining, hard-to-avoid non-CO₂ emissions will become. Relative to an abundant literature on mitigation options for CO₂, non-CO₂ abatement studies are relatively scarce. This leads to outdated and inconsistent datasets, which sometimes are difficult to integrate into economic models. Two new studies therefore are of interest to the IAM community:

A new study by Harmsen et al (2019) provides an almost complete (91% coverage of non-CO₂ emissions) dataset of non-CO₂ abatement cost curves. This dataset provides an update to a widely used, but outdated global, long-term dataset. It further improves existing data by a better coverage of high cost abatement options, increased consistency between different world regions and a representation of inertia in mitigation policy (i.e. path-dependency). Compared to the older dataset, global GHG abatement potentials are similar; however, the contribution of different gases and emission sources has changed. With the new data set, policy costs are higher, especially due to abatement options in the agricultural sector.

A study by Weitzel et al. (2019) is complementary to the dataset. A new framework is presented that allows integrating detailed bottom-up abatement data into a top-down economic model without losing too much detail. The framework allows to better capture non-linearities in the marginal abatement cost curves that follow from the representation of explicit technologies. This avoids over- or underestimation of abatement costs that simplify the bottom-up cost curves. In principle, the framework would also allow to capture indirect effects, e.g. that an energy intensive end-of-pipe abatement option could become more costly in a scenario in which energy prices increase.

References:

• Harmsen, J. H. M., et al. “Long-term marginal abatement cost curves of non-CO₂ greenhouse gases.” Environmental Science & Policy 99 (2019): 136-149. https://doi.org/10.1016/j.envsci.2019.05.013
• Weitzel, Matthias, Bert Saveyn, and Toon Vandyck. “Including bottom-up emission abatement technologies in a large-scale global economic model for policy assessments.” Energy Economics 83 (2019): 254-263. https://doi.org/10.1016/j.eneco.2019.07.004

For the dataset, see https://doi.org/10.1016/j.dib.2019.104334