Examples projects and applications

Here is a selection of prior research activities highlighting Em2MG capabilities and collaborations:

• Assessing the air pollutant and health co-benefits associated with deep decarbonization:

  • Loughlin, D., Barron, A., Basnet Chettri, et al. (2024). Health and air pollutant emission impacts of Net Zero CO2 by 2050 scenarios from the Energy Modeling Forum 37 study. Energy and Climate Change, 5(2024), 100165. https://doi.org/10.1016/j.egycc.2024.100165. This study examines the air pollutant emissions projections for six Integrated Assessment Models (IAMs), both with and without a Net Zero CO2 target. While the study finds that the projections are notably different across models, these differences are largely explainable based upon model scope, structure, and assumptions. Furthermore, despite these differences, the Net Zero target consistently resulted in significantly reduced air pollutant emissions across all the models. The EPA’s CO-Benefits Risk Assessment (COBRA) tool was applied to emission results of three models. This screening tool suggested that there would be widespread air quality and health benefits across the U.S. when targeting deep decarbonization.

  • Ou, Y., Iyer, G., McJeon, H., Cui, R., Zhao, A., O’Keefe, K.T.V., Zhao, M., Qiu, Y., and D.H. Loughlin (2023). State-level energy-water-land-health analysis of the US net-zero emissions goal. Energy and Climate Change, Oct. https://doi.org/10.1016/j.egycc.2023.100117.  This study demonstrates the ability of the GCAM-USA human-Earth systems model to inform the quantification of energy, water, land, and health impacts of alternative pathways for achieving a Net-Zero CO2 goal. Findings include significant capital turnover and stranded assets, reduced demand fo rwater withdrawals, expanded forest land, and large air quality-related health benefits.

• Understanding the air pollutant and greenhouse gas impacts of new and emerging energy technologies:

  • Ou, Y., Kittner, N., Smith, S.J., Babaee, S., Nolte, C.G., and D.H. Loughlin (2021). Evaluating long-term emission impacts of large-scale electric vehicle deployment in the US using a human-earth systems model. Applied Energy, 300(2021), 117364. https://doi.org/10.1016/j.apenergy.2021.117364. This study suggests that significant air pollutant emission reductions can be achieved through electrification of the U.S. onroad light-duty fleet. The study also highlights modeled outputs, such as price-induced fuel switching in other sectors and caveats these by discussing the model’s limited representations of refining and other industries. Recommendations are made for model improvements to address questions surrounding vehicle electrification more fully.

• Incorporating energy efficiency, renewable energy, and fuel switching into air quality management strategies:

  • Loughlin, D.H., Macpherson, A.J., Kaufman, K.R., and B.N. Keaveny (2017). Marginal abatement cost curves for NOx that incorporate control measures, renewable energy, energy efficiency and fuel switching. Journal of the Air and Waste Management Assoc., 67(10), 1115-1125. DOI: https://doi.org/10.1080/10962247.2017.1342715. Efforts to calculate the costs and benefits of reducing air pollutant emissions have typically focused on “end-of-pipe” controls that remove those emissions from exhaust gases. “Nontraditional” control measures are also available, including energy efficiency, renewable energy, and fuel switching to lower- or zero-carbon fuels. These controls are difficult to consider in a cost-benefit analysis because their cost-effectiveness (e.g., $/ton of pollutant removed) is not straightforward to calculate. In this study, we use the MARKAL energy system model to develop marginal abatement cost curves for nitrogen oxide (NOx) emissions. The curves indicate strategies for achieving specific emissions reductions through cost-effective combinations of end-of-pipe and non-traditional controls.

• Innovative approaches for developing air quality management strategies:

  • Ou Y., West, J.J., Smith, S.J., Nolte, C.G., and D.H. Loughlin (2020). Air pollution control strategies directly limiting national health damages in the US. Nature Communications, (2020)11:957, https://doi.org/10.1038/s41467-020-14783-2. In developing air pollution control strategies, one approach is to iterate over a small set of potential emission reduction level (often 2 to 3), using air quality modeling to determine the air pollution levels associated with each. Based on the results, an emission reduction target to achieve an air pollution goal is estimated. Controls are then chosen to achieve the targeted reductions. This approach is practicable, but can be time consuming. Furthermore, the complexities of pollutant chemistry and transport may result in the controls under- or over-shooting the air quality target. Here we demonstrate an alternative in which health impact factors are integrated directly into the GCAM-USA human-Earth systems model. GCAM-USA is then used to automate the process of finding emission control strategies that meet a health benefit target. In selecting a control strategy, GCAM-USA simultaneously considers the cost-effectiveness of both tradtional and non-tradition controls, considering options across all sectors of the economy. In this study, we demonstrate the use of this novel approach to identify state-specific strategies for reducing the mortality costs associated with fine particulate matter.

  • Babaee, S., Loughlin, D.H., and P.O. Kaplan (2020). Incorporating upstream emissions into electric sector nitrogen oxide reduction targets. Cleaner Engineering and Technology, https://doi.org/10.1016/j.clet.2020.100017. In designing power sector emission control requirements, one option would be to provide utilities with credits for reducing upstream emissions, such as from coal mining and natural gas extraction. In this analysis, compared the performance of (i) a cap on power sector NOx emissions, and (ii) a cap included both power sector and upstream emissions. The caps were designed to achieve the same overall NOx reductions. While modeling the latter approach resulted in lower control cost, it also had a disbenefit: increases in emissions of other pollutants, including particulate matter (PM) and sulfur dioxide (SO2). This result was because the additional flexibility allowed some of the older, higher PM- and SO2-emitting power plants to remain in service. This study provides valuable insights about the tradeoffs between cost and flexibility, as well as the need for careful policy design to avoid unintended consequences.