
Nicholas Z. Muller
Professor Carnegie Mellon University
- Pittsburgh PA
Nicholas Muller works at the intersection of environmental policy and economics.
Biography
Areas of Expertise
Media Appearances
Wildfire smoke associated with 20,000 premature deaths and billions in damages
Pittsburgh Post-Gazette online
2025-05-04
CMU scientists project that wildfires were associated with 20,000 premature deaths and $200 billion in damages across the country in 2017. “These [air pollution] damages from wildfires are comparable to the [air pollution damages] from the entire manufacturing sector in the U.S., which is staggering,” said Nicholas Muller (Tepper School of Business)
Wildfire smoke and prescribed burns caused 20,000 early deaths and billions in damages in just one year
MSN online
2025-04-09
A new study led by Nicholas Muller (Tepper School of Business) estimates that wildfire and prescribed burn smoke caused $200 billion in health damages and 20,000 premature deaths in 2017, with senior citizens and marginalized communities suffering the most.
Regulators underrate air pollution mortality by $100B, ignore racial gaps: study
The Hill online
2021-12-21
“Underlying mortality rates, pollution exposure and pollution vulnerability differ significantly across racial and ethnic groups,” Nicholas Z. Muller, study co-author and a professor of economics, engineering and public policy at Carnegie Mellon University’s Tepper School of Business, said in a statement.
135 million Americans are breathing unhealthy air, American Lung Association says
NBC News
2021-04-22
“Generally, there are two local air pollutants that the U.S., EPA, and other researchers tend to focus on,” explained Nicholas Muller, associate professor of economics, engineering, and public policy at Carnegie Mellon University. “Those are fine particulate matter and tropospheric or ground-level ozone.”
Study: US air pollution deaths increased by 9,700 a year from 2016 to 2018
Vox online
2019-10-24
The researchers, Karen Clay and Nicholas Muller, argue that some of the increase is due to non-regulatory factors, like an increase in wildfires and economic growth. But they note a decline in Clean Air Act enforcement under Donald Trump that could be responsible as well.
America’s Air Quality Worsens, Ending Years of Gains, Study Says
The New York Times online
2019-10-24
“After a decade or so of reductions,” said Nick Muller, a professor of economics, engineering and public policy at Carnegie Mellon, and one of the study’s co-authors, “this increase is a real about-face.”
New study: US air pollution rose from 2016-2018, resulting in premature deaths
The Hill online
2019-10-23
“That increase was associated with 9,700 premature deaths in 2018,” Karen Clay and Nicholas Muller, economists with Carnegie Mellon, wrote in a paper published by the National Bureau of Economic Research.
Social
Industry Expertise
Accomplishments
United States Environmental Protection Agency Scientific and Technological Achievement Award, Level II
2013
Education
Yale University
Ph.D.
Environmental and Natural Resource Economics
2007
Indiana University
M.P.A.
Environmental Policy & Public Financial Administration
2002
University of Oregon
B.S.
Public Policy, Planning and Management
1996
Affiliations
- Wilton E. Scott Institute for Energy Innovation
Links
Articles
Marginal abatement costs for greenhouse gas emissions in the United States using an energy systems approach
Environmental Research Energy2025
Deep decarbonization requires fundamental changes in meeting energy service demands, with some efforts increasing overall costs. Examining abatement measures in isolation, however, fails to capture their interactive effects within the energy system. Here we show the abatement costs of decarbonization in the United States using an energy system optimization model to capture technological interactions, multi-decadal path dependence, and endogenous end-use technology selection. Energy-system-wide net-zero CO2-eq emissions are achieved in 2050 at a cost under $400 per tonne CO2-eq, led by emissions reductions in power generation, end-use electrification of ground transportation, space heating, and some industrial applications. Differences in mitigation costs and CO2 geological storage potential lead to regional heterogeneities in mitigation rates and residual emissions. The marginal abatement cost curves show that additional decarbonization comes at higher incremental costs, this cost penalty decreases over time, and substantially greater abatement occurs in future time periods at the same abatement cost.
Socially vulnerable communities face disproportionate exposure and susceptibility to US wildfire and prescribed burn smoke
Communications Earth & Environment2025
While air pollution from most U.S. sources has decreased, emissions from wildland fires have risen. Here, we use an integrated assessment model to estimate that wildfire and prescribed burn smoke caused $200 billion in health damages in 2017, associated with 20,000 premature deaths. Nearly half of this damage came from wildfires, predominantly in the West, with the remainder from prescribed burns, mostly in the Southeast. Our analysis reveals positive correlations between smoke exposure and various social vulnerability measures; however, when also considering smoke susceptibility, these disparities are systematically influenced by age. Senior citizens, who are disproportionately White, represented 16% of the population but incurred 75% of the damages. Nonetheless, within most age groups, Native American and Black communities experienced the greatest damages per capita. Our work highlights the extraordinary and disproportionate effects of the growing threat of fire smoke and calls for targeted, equitable policy solutions for a healthier future.
The Role of Hydrogen in Decarbonizing US Iron and Steel Production
Environmental Science & Technology2025
This study investigates the role of hydrogen as a decarbonization strategy for the iron and steel industry in the United States (U.S.) in the presence of an economy-wide net zero CO2 emissions target. Our analysis shows that hydrogen-based direct reduced iron (H2DRI) provides a cost-effective decarbonization strategy only under a relatively narrow set of conditions. Using today's best estimates of the capital and variable costs of alternative decarbonized iron and steelmaking technologies in a U.S. economy-wide simulation framework, we find that carbon capture technologies can achieve comparable decarbonization levels by 2050 and greater cumulative emissions reductions from iron and steel production at a lower cost. Simulations suggest hydrogen contributes to economy-wide decarbonization, but H2DRI is not the preferred use case for hydrogen in most scenarios. The average abatement cost for U.S. iron and steel production could be as low as $70/tonne CO2 with existing technologies plus carbon capture, while the cost with H2DRI rises to over $500/tonne CO2. We also find that IRA tax credits are insufficient to spur hydrogen use in steelmaking in our model and that a green steel production tax credit would need to be as high as $300/tonne steel to lead to sustained H2DRI use.
Climate Policy Reduces Racial Disparities in Air Pollution from Transportation and Power Generation
Environmental Science & Technology2024
Energy system optimization models facilitate analyses on a national or regional scale. However, understanding the impacts of climate policy on specific populations requires a much higher spatial resolution. Here, we link an energy system optimization model to an integrated assessment model via an emission downscaling algorithm, translating air pollution emissions from nine U.S. regions to U.S. counties. We simulate the impacts of six distinct policy scenarios, including a current policy and a 2050 net-zero target, on NO x , SO2, and PM2.5 emissions from on-road transportation and electricity generation. We compare different policies based on their ability to reduce emission exposure and exposure disparity across racial groups, allowing decision-makers to assess the air pollution impacts of various policy instruments more holistically. Modeled policies include a clean electricity standard, an on-road ICE vehicle ban, a carbon tax, and a scenario that reaches net-zero GHG emissions by 2050. While exposure and disparities decrease in all scenarios, our results reveal persistent disparities until at least 2040, particularly for Black non-Hispanic Americans. Our estimates of avoided deaths due to air pollution emphasize the importance of policy timing, showing that thousands of lives can be saved by taking action in the near-term.
Funding a Just Transition Away from Coal in the U.S. Considering Avoided Damage from Air Pollution
Journal of Benefit-Cost Analysis2024
Coal is declining in the U.S. as part of the clean energy transition, resulting in remarkable air pollution benefits for the American public and significant costs for the industry. Using the AP3 integrated assessment model, we estimate that fewer emissions of sulfur dioxide, nitrogen oxides, and primary fine particulate matter driven by coal's decline led to $300 billion in benefits from 2014 to 2019. Conversely, we find that job losses driven by less coal plant and mining activity resulted in $7.84 billion in foregone wages over the same timeframe. While the benefits were greatly distributed (mostly throughout the East), costs were highly concentrated in coal communities. Transferring a small fraction of the benefits to workers could cover these costs while maintaining societal net benefits. Forecasting coal fleet damages from 2020 to 2035, we find that buying out or replacing these plants would result in $589 billion in air quality benefits, which considerably outweigh the costs. The return on investment increases when policy targets the most damaging capacity, and net benefits are maximized when removing just facilities where marginal benefits exceed marginal costs. Evaluating competitive reverse auction policy designs akin to Germany's Coal Exit Act, we find that adjusting bids based on monetary damages rather than based only on carbon dioxide emissions - the German design - provides a welfare advantage. Our benefit-cost analyses clearly support policies that drive a swift and just transition away from coal, thereby clearing the air while supporting communities needing assistance.