Assessing Pathways to a Net-Zero Energy System, with Erin Mayfield

Notable Quotes

• Decarbonization can be affordable: “The effort [to decarbonize] is going to be big and unprecedented in many ways, but the transition is also affordable in aggregate. One way to contextualize the effort is to compare energy system costs to the share of gross domestic product spent on energy. Over the past 50 years, there’s been a lot of volatility … During the Great Recession, for instance, energy costs were about 10 percent of GDP. Looking forward, we show across all the different net-zero pathways that we model, the annualized cost of transitioning as a share of GDP over the next 30 years is lower than historical levels.” (9:29)
• Meeting climate goals will require more renewable energy infrastructure: “In the first five years of the transition, the [renewables] deployment rate will have to be equivalent to the historical maximum deployment rate that we observed in the United States. In the five years after that, this deployment rate will have to double, and the deployment rate continues to accelerate thereafter … We estimate that we’ll need to devote between 90,000 to 400,000 square miles of land to wind farms, for example, in order to meet our net-zero goal. The visual footprint—the area throughout which you would likely be able to see the turbines—could be as big as the combined area of Nebraska, Iowa, Kansas, Missouri, Oklahoma, and Arkansas.” (14:15)
• Impacts of the clean energy transition on fossil fuel workers: “As the economy decarbonizes, we find that there are going to be acute job losses in specific communities where mining has historically been the dominant employer … This is where effective and equitable policy plays a really large role. How do we moderate these transition risks to ensure that communities don’t collapse or decline?” (25:52)

Top of the Stack

• Net-Zero America by Eric Larson, Chris Greig, Jesse Jenkins, Erin Mayfield, Andrew Pascale, Chuan Zhang, Joshua Drossman, Robert Williams, Steve Pacala, Robert Socolow, Ejeong Baik, Rich Birdsey, Rick Duke, Ryan Jones, Ben Haley, Emily Leslie, Keith Paustian, and Amy Swan
• The Foxes painting by German expressionist artist Franz Marc
• The art of Erin Mayfield’s eight-year-old nephew, Vinny
• Accelerating Decarbonization of the U.S. Energy System from the National Academies of Sciences, Engineering, and Medicine, by Stephen W. Pacala, Colin Cunliff, Danielle Deane-Ryan, Kelly Sims Gallagher, Julia Haggerty, Christopher T. Hendrickson, Jesse D. Jenkins, Roxanne Johnson, Timothy C. Lieuwen, Vivian Loftness, Clark A. Miller, William A. Pizer, Varun Rai, Ed Rightor, Esther Takeuchi, Susan F. Tierney, and Jennifer Wilcox

The Full Transcript

Daniel Raimi: Hello, and welcome to Resources Radio, a weekly podcast from Resources for the Future. I'm your host, Daniel Raimi. Today, we talk with Dr. Erin Mayfield, a postdoctoral fellow at Princeton University. Erin is part of a team of researchers that recently released a report titled Net-Zero America, which lays out a variety of pathways for the United States to reach net-zero greenhouse gas emissions by 2050. In today's conversation, Erin will help us understand some of the key findings from the report, including how much the transition might cost, how much new infrastructure we need to build, and what effects we might see on energy sector employment. We'll also talk about the models the team used to generate these results, including a discussion of the limitations of models in addressing complex social issues. Stay with us.

Alright, Dr. Erin Mayfield from Princeton University. Thank you so much for joining us today on Resources Radio.

Erin Mayfield: Thank you. Happy to be here.

Daniel Raimi: We're going to talk today about a report that you were a part of called the “Net-Zero America” report, which is just a fascinating piece of work. And we're going to dive deep into it, or as deep as we can in 30 minutes. But before we do that, can you tell us how you got interested in working on energy and environmental issues in the first place?

Erin Mayfield: My environmental origin story takes place in New Jersey where I grew up. As long as I can remember, a core part of my identity has been a deep respect for and love of nature. A lot of that was probably innate, but my environmental ethic was certainly fostered from spending many weekends of my childhood hiking in the woods with my family. Part of my environmental ethic also stems from growing up in New Jersey, which is an exceptional state in many respects, one being that it has the highest density of contaminated sites of any state. So, environmental devastation was also really visible. As a kid, I knew that when I grew up, I wanted to do something related to the environment or animals. I originally wanted to be a cowgirl, which I thought at the time just meant spending time with cows, so my aspirations have morphed over time and I ended up majoring in environmental science as an undergrad.

My first job out of college was working on remediating contaminated sites in New Jersey, many of which were in low-income and minority communities. I've also had other jobs over the years like working on rulemakings at the US Environmental Protection Agency and interning for climate change–denying congressmen, and working on natural resource damage negotiations related to the Deepwater Horizon oil spill. I eventually entered into a PhD program, very clear-eyed about how decisions are made and the many ways in which we can improve computational tools to better support decisionmaking.

Daniel Raimi: That's a fascinating range of experiences. Wow. I had no idea you had all those different experiences in your past. Did you ever to like intern as a cowgirl or do anything fun like that?

Erin Mayfield: No. I never had any job where I got to associate with cows, unfortunately.

Daniel Raimi: That's sad. Well, you're still young. There is plenty of time ahead. So, let's dig in now to the “Net-Zero America” report. As I mentioned, you're part of a big team that put together this report, which lays out a variety of pathways for the United States to achieve net-zero emissions across the entire economy by 2050. I'm going to ask you all sorts of unfair questions today, but the first one is whether you can give us just a high-level overview of the topics that are covered in the report.

Erin Mayfield: So this was a two-year study carried out by a large Princeton-led research team with the aim of informing policymakers as well as private sector decisionmaking. There have been a slew of decarbonization reports over the past several months, looking at different pathways to reach net-zero or other emission targets. Our study is a bit unique because of its high degree of geographic and temporal granularity, with the hope of making these transitions understandable at a human scale. What does it take for the United States to achieve net-zero? What do these transitions apply for how Americans use energy and how energy is supplied? We also wanted to quantify the inherent challenges and opportunities of these transitions. So the granularity allows us to assess, at the state and local level, implications for things like infrastructure. Where do we actually site new transmission, solar, and wind over time? How do thermal facilities evolve over time?

Then we also did deep dives into other parts of the supply chain to see what happens to things like incumbent fossil fuel supply chains and the potential for asset stranding. We also analyze costs and financing, such as the level of capital that you'll need to mobilize to build out and maintain this infrastructure. Then we looked at impacts as well, leveraging this large degree of granularity in our infrastructure siting. We looked at impacts to land use, so how renewables and transmission is going to transform the physical landscape in many areas. We also looked at labor impacts and workforce development needs to support these transitions in addition to air pollution–related health impacts, or benefits from the declining use of fossil fuel. There's a large breadth of things that we covered in the study. Taken together, we wanted to not only look at the broad contours of what these net-zero transitions are, but also some of the details that can help further focus our efforts with respect to investing and really how we manage these transitions.

Daniel Raimi: That's great. For the members of our audience who haven't checked out this report, I'd really encourage you to do so. We'll have a link to it in our show notes. The slide deck also captures a lot of the findings; it's several hundred pages long, but it's full of really amazing detail and maps and graphs and bullet points that give you some of the key messages of the report. Erin, when you step back and think about the many topics that you covered in the report and all of the granularity that you just mentioned—this is sort of an unfair question—but in your view, what are the two or three most important take-home messages that you hope people get when they look through your report?

Erin Mayfield: There are many, but I'll limit it to three. The first thing that's relevant, not only to policymakers, but also to developers and investors, is we created a blueprint for immediate action. What do we have to do in the next 10 years? In the next decade, across all different net-zero pathways, the trajectory is quite similar, and the resources we need to deploy are similar. In other words, we look at what needs to be accomplished in the 2020s to be on track for net zero by 2050. So, we estimate the additional capital that needs to be mobilized in the 2020s relative to the business-as-usual scenario. We estimate that to be on the order of $2.5 trillion. Investments are nearly identical across all the net-zero scenarios in that first decade, so we have to invest in a lot of solar and wind and transmission in the near term.

We also have to invest on the consumer side in energy efficiency and innovation. Instead of spending the next decade squabbling over the last 10 percent of the transition, we can really focus on reducing transition risk and leaving as many options open as we can, so we’re prepared down the line to continue rapidly cutting emissions. The second thing, and maybe the most compelling part of the report, is the scale and the pace of transition. We have to build out all types of infrastructure and, in many cases, at unprecedented rates. But in these transitions, we have potentially many degrees of freedom, or options, with respect to where we site infrastructure, not only solar and wind electric power capacity, but also how we transition and site thermal and industrial facilities. We have the opportunity to also think strategically about how we can also site manufacturing to benefit communities and build broader support to help achieve our mission goals.

A third related take-home is that there are going to be distributional benefits and costs in terms of things like job creation and loss, and also reduction in air pollution. We really have the opportunity to mitigate some of the existing inequities that are embedded within our energy system.

Daniel Raimi: That's great. We're going to dig into at least a couple of those items now over the next few minutes. You mentioned the scale of investment over the next decade of roughly $2.5 trillion under most of the scenarios, or perhaps all of the scenarios. When people hear that number, there may be an inclination to think that as we shift away from fossil energy, there's sort of an assumption that this scale of investment will lead energy costs to rise considerably. Can you talk a little bit about what your team found in the modeling and also help us understand what are some of the big assumptions that you made to reach those conclusions?

Erin Mayfield: The main line here is that the effort is going to be big and unprecedented in many ways, but the transition is also affordable in aggregate. One way to contextualize the effort is to compare energy system costs to the share of gross domestic product spent on energy. Over the past 50 years, there's been a lot of volatility stemming from things like oil price shocks and the Great Recession. During the Great Recession, energy costs were about 10 percent of GDP. Looking forward, we show across all the different net-zero pathways that we model that the annualized cost of transitioning as a share of GDP over the next 30 years is lower than historical levels. There are also a lot of assumptions that go into modeling costs of these future systems, and so structurally, at a high level, we are selecting least-cost pathways to achieve our emissions targets over time.

In other words, we're optimizing for the total system costs over the life of the transition, given perfect information about future technology costs and learning curves. We're also assuming perfect foresight and the capacity to seamlessly integrate energy supplies, demand across all these different sectors. We're also assuming rational and efficient markets in response to which investors are able to mobilize capital instantly or overnight. In reality, transitions are much more complex than that. As a modeler, one should always be very acquainted with the limitations of distilling the complexity of the real world. It requires a large dose of humility, and to be able to say what we really don't know. These models are not meant to be predictive. In my opinion, the purpose of modeling the pathways is to clarify the contours of what could be, what we need to plan for, or what the consequences of our choices are, what the trade-offs are, and how do we reduce transition risks.

Actually the core of my main research acknowledges the utility of models to provide insight but also the frailty of most models to address the social and political objectives and constraints that may drive our policy and planning processes. The core framing of most of what I do is around explicitly incorporating cumulative impacts and social equity objectives into our computational decision support tools. How do we select and manage these transitions to, for example, maximize the flow of benefits to vulnerable communities, or ensure the fair distribution of labor, or minimize air pollution-related impacts?

Daniel Raimi: That's so fascinating. It brings to mind the old saw that I'm sure you've heard a million times, which is, “All models are wrong; some are useful.” It seems like your work both on this report and in the other streams of work that you do is helping us sort of understand the limitations of the models and what we can learn from them despite their imperfections.

Erin Mayfield: Certainly, that saying is a tenet in how I think about modeling and how I think about my research and contributions.

Daniel Raimi: Related to this question of model optimization and the complexities of the real world, one of the things that I was wondering about as I read through the report is the challenge of siting infrastructure. As you've mentioned a couple of times, there will be a need to build lots and lots of stuff: solar facilities, wind facilities, transmission, CO₂ pipelines, and other infrastructure. Can you talk a little bit about the scale of that infrastructure build-out and maybe help us intuit it a little bit more and also address the barriers that might stand in the way of deploying infrastructure at such a large scale?

Erin Mayfield: The scale and the pace of the infrastructure build-out is truly astounding. Starting with wind and solar, we model a range of net-zero pathways and across these pathways, solar and wind comprises between 45 percent and 100 percent of electricity supply by 2050. Let’s focus on just one of these net-zero pathways that is relatively moderate in terms of renewable deployment, in which means solar and wind comprise only about 80 percent to 90 percent of electricity supply by 2050 in this scenario. To contextualize the build-out for this scenario, we had about 100 gigawatts of wind and 35 gigawatts of utility-scale solar at the end of 2019. We will need to have built one and a half terawatts by 2050. That is over a tenfold increase in solar and wind capacity expansion. We can think about the deployment rates or the pace of the build-out as well.

In the first five years of the transition, the deployment rate will have to be equivalent to the historical maximum deployment rate that we observed in the United States. In the five years after that, to 2030, this deployment rate will have to double, and the deployment rate continues to accelerate thereafter. There's a similar pattern for transmission, which expands by about 60 percent from 2020 to 2030, and by 2050, transmission nearly triples. So as Jesse Jenkins, one of the lead researchers on the “Net-Zero America” study puts it, it took 150 years to build the current grid, and now we have to build that much transition in the next 15 years, and then again, in 15 years after that. We're building all types of other infrastructure and supply chains as well. We model the build-out of the biomass resource sector in addition to the build-out of CO₂ pipeline networks.

There's all of this infrastructure being built out all at once. If you look at the maps of the build-out in the report, you can see how truly widespread it is. These infrastructure build-outs affect every state and many locales. We estimate that we'll need to devote between 90,000 to 400,000 square miles of land to wind farms, for example, in order to meet our net-zero goal. The visual footprint—the area throughout which you would likely be able to see the turbines—could be as big as the combined area of Nebraska, Iowa, Kansas, Missouri, Oklahoma, and Arkansas.

Daniel Raimi: Wow.

Erin Mayfield: These expansive impacts on landscapes and communities will have to be mitigated and managed. The scale of build-out also presents a transition risk requiring the need to foster and build broader support and social license. And we already observe local opposition, which may become even more constraining over time without good management. We also have to ensure that communities are benefiting and have a voice and are recognized in these transitions. The way that we model the build-out and decide where we site infrastructure in the study is also based on least cost principles, given different spatial constraints related to technical and environmental factors. We're currently trying to model alternative scenarios based on different siting principles, such that there are more equitable distributions of infrastructure, and explicitly trying to account for things like environmental justice and just transitions directly in our siting algorithms.

Daniel Raimi: That's so interesting. I would love to ask you more questions about that, and maybe I will over time and we won't get into all the nitty-gritty on the podcast, but I'm just fascinated by those issues. We did an episode on this podcast with Sarah Mills, who's a scholar at University of Michigan over a year ago now about her work related to sort of public support for wind energy deployment. And a lot of the things that she has insights into definitely plays into some of those modeling algorithms that I'm sure are going into your future work. So, let's transition now and talk about a portion of the report that I think you played a key role in, if not a leading role, which is looking at some of the socioeconomic implications of achieving net-zero by mid-century. You led the portion of the analysis that was focused on the effects of energy transition on jobs. Can you tell us again what some of the high-level overview findings are when it comes to energy transition and employment? What are some of the major assumptions that underpin them?

Erin Mayfield: Achieving a net-zero emissions goal by 2050 entails transforming the energy workforce. We developed a labor model tailored to the context of long-term energy transitions, and really tried to leverage all the geospatially resolved energy system activity projections from the rest of the study. Then we developed a tool to model employment wages and workforce development needs, really trying to focus on details that may inform regional and national workforce and infrastructure planning and policymaking. When it comes to labor, there's always these very top-line findings of massive job creation. At an aggregate level, we find that the net-zero transition supports an annual average of about 3 million direct supply-side related jobs, or $200 billion in wages during the first decade of the transition. This is a net increase in energy jobs of about a half million to 1 million jobs above our business-as-usual scenario.

The modeled energy workforce represents about 1.5 percent of the total US workforce in 2020, increasing to about 2.5 percent to upwards of 5% by mid-century. There's a lot of variation in our different labor pathways associated with our different net-zero pathways. These labor pathways are influenced by a lot of policy-mediated factors, such as technology selecting the pace of the infrastructure transition and where we site and invest in different things. A key part is also changes in labor productivity over time. We anticipate that there's going to be increases in labor productivity, which in part drives down our technology costs. This is in part because we're talking about solar and wind, which are industries that exist now, but they're going to be rapidly expanding over time. We anticipate increasing economies of scale in learning and automation.

There's also a lot of variation in potential future labor pathways, based on the extent of domestic manufacturing as well and different policy supports for increased domestic content shares. We also show that there's boom and bust cycles that arise. So employment wages and losses in our declining fossil fuel sectors are offset at a very aggregate level by increases in low-carbon resource sectors. We show that most states have the potential to experience long-term expansion in the energy workforce, potentially transforming some state economies, but there is also a substantial state-level variation in our different labor pathways. How that variation and those changes play out are highly uncertain and are going to depend a lot on socio-technical factors that—some of which, but not all—we can manage.

There's some level of flexibility that can be leveraged to help facilitate building political coalitions, bargaining, as well as trying to reduce transition risks. Local, federal, and state policies can be designed to more equitably distribute some of the labor benefits and moderate some of the volatile labor cycles that may arise. Again, there's many degrees of freedom with respect to where we site, not only in renewable generation, but also manufacturing as well.

Daniel Raimi: The policy decisions that will shape those things are so interesting and nuanced, and it's something that I've been working on a lot lately. So again, more for us to talk about when we're done with the podcast interview. One of the challenges in modeling labor outcomes, as I understand it—and please correct me if I'm wrong, because I'm definitely not the expert here—is that it can be hard to approximate the barriers that folks might face in finding new employment. So if you lose a job in coal mining or a coal power plant, the model might assume that it's relatively easy or costless for an individual to find new employment in a new sector. I may have mischaracterized the way that your modeling treats these issues, but can you give us a little bit of a sense of how the modeling in this report treats those issues of labor flows over time?

Erin Mayfield: We model the flows of over 1,000 different occupations over time and the demand for these occupations in different states and regions. We also modeled the training, education, and experience requirements, finding that there's a diversity of workforce development needs, which are going to be similar to historical transitions, but at a much, much larger scale over a sustained time period of 30 years or more than 30 years. We find that approximately 70 percent of the energy workforce is going to require less than four years of related work experience. About 70 percent of the energy workforce is going to require less than a bachelor's degree to participate in the energy economy. This kind of analysis can help plan and better assure the adequacy of the workforce skills and experience in the right place and time to help reduce transition risks. So the rate of decarbonization is itself influenced by the organization and availability of labor.

We're talking about potentially expanding the energy workforce by sevenfold. Then this is going to require sustained support for workforce development programs that are diverse and meet the needs of communities and workers. In existing energy labor markets, there is already evidence of difficulty in hiring, which portends that there's going to be continued employment bottlenecks in the future decarbonization without countervailing policies and organization. There's also mounting policy and political discourse regarding just transitions and embedding social equity goals and high-road labor policies into climate policy. High-road labor policies may include things such as prevailing wage standards, local labor standards to ensure those jobs are accessible to members of the communities where infrastructure is being sited, and increasing the domestic content share of manufactured products across the low-carbon supply chain to support domestic job creation. This may include just transition funds as well to help and potentially compensate displaced workers.

Daniel Raimi: We're seeing evidence of that as we speak in Congress. All sorts of bills have been proposed and discussed recently to start making some of those investments that you're describing. Last question, Erin, before we go to our Top of the Stack segment. I'm hoping you can speak a little bit to that last issue you've raised of communities in transition, those that currently depend on coal oil, gas, or power plants for an outside share of the local economy. Parts of the Gulf Coast, parts of Appalachia, a lot of the state of Wyoming, parts of Texas and Oklahoma, and elsewhere. Can you give us a sense of what your results imply for those communities and the people that live there?

Erin Mayfield: If we take coal, for example, employment across the coal supply chain represents about 5 percent of the total supply-side energy workforce, employing about 150,000 workers. But coal employment is spatially clustered in mining regions, including in Appalachia and the Powder River Basin. The coal represents about 2 percent of the labor force as of 2021 about now in West Virginia. However, the coal mining industry is a dominant employer in several counties, directly employing 5 percent or greater of the total workforce in 35 counties across the country, an upwards of 25 percent of the labor force in one West Virginia county. As the economy decarbonizes, we find that there are going to be acute job losses in specific communities where mining has historically been the dominant employer. We see other context-specific issues related to oil and gas regions. This is where effective and equitable policy plays a really large role.

How do we moderate these transition risks to ensure that communities don't collapse or decline? In some areas, like Texas, we don't find that there's a net loss in jobs over the entire 30 years that we model. All of the oil and natural gas jobs are offset by solar, wind, and transmission jobs. This doesn't mean that there's going to be perfect complementarity in terms of geography and occupational skills between our declining fossil fuel industries and our growing low-carbon industries. Again, this is where we need to manage transitions and ensure that they're just.

Daniel Raimi: That's really nicely explained. Well, Erin, as our listeners have a sense at this point, this work that you and your colleagues have done is incredibly rich and fascinating, and we could talk about it for hours and hours, but we are going to call it a day for now and move on to our Top of the Stack question, which is asking you what you've read or heard or watched recently related to the environment, even if tangentially, that you think is really interesting and that you'd recommend to our listeners. I'll start just with a very quick recommendation of another very long, detailed and fantastic report about energy transition that came out recently from the National Academies of Sciences, Engineering, and Medicine. Some of the authors on that report are some of the same authors that are on the Net-Zero America report that we've been talking about today, but there's sort of a different angle with the National Academies report.

There's a really deep focus on these issues of energy transition and transition risk, along with the policies that the federal government can deploy to support those coal communities and oil communities and gas communities as we go into a low-carbon future. The name of that report is Accelerating Decarbonization in the United States: Technology, Policy, and Societal Dimensions. It's another really great piece of work and a fantastic complement to the Net-Zero America report that we've been discussing today. I've been reading lots of long reports lately. How about you, Erin? What's on the top of your literal or metaphorical reading stack?

Erin Mayfield: Knowing that it was going to be a very busy few months given the policy environment, and having really exhausted all the binge-worthy Netflix shows, I made the life-changing decision to cancel my Netflix account and really have had few moments to read good novels. Instead I'm going to recommend art. Specifically, I want to recommend the work of my favorite artist, Franz Marc, who was a German expressionist painter. His work is mostly of animals in these very vibrant colors. My favorite painting, which I want to print out, is called The Foxes. My other favorite artist is my eight-year-old nephew, Vinny, who is a very creative spirit and who loves to draw really fun scenes of nature and anthropomorphizes everything under the sun, including the sun and rocks and volcanoes. My recommendation is the collected works of Franz Marc and my nephew, Vinny.

Daniel Raimi: That's so great. Is Vinny published yet? Does he have a book or an Instagram page that we could link to?

Erin Mayfield: No, but I can get a photo of his latest work.

Daniel Raimi: That sounds great. I'm sure there will be a clamor from our audience to get a hold of Vinny's latest anthropomorphizing. That's really great. Well, Erin, I think you're the first person that's recommended visual art on your Top of the Stack. So, that is an absolute plus for us. Thank you so much for that recommendation. It sounds fantastic. One more time, Erin Mayfield from Princeton University. Thank you so much for joining us on Resources Radio and telling us about this fascinating work.

Erin Mayfield: Thanks for having me.

Daniel Raimi: You've been listening to Resources Radio. Learn how to support Resources for the Future at rff.org/support. If you have a minute, we'd really appreciate you leaving us a rating or comment on your podcast platform of choice. Also, feel free to send us your suggestions for future episodes. Resources Radio is a podcast from Resources for the Future. RFF is an independent non-profit research institution in Washington, DC. Our mission is to improve environmental, energy and natural resource decisions through impartial economic research and policy engagement.

The views expressed on this podcast are solely those of the podcast guests and may differ from those of RFF experts, its officers or its directors. RFF does not take positions on specific legislative proposals. Resources Radio is produced by Elizabeth Wason, with music by me, Daniel Raimi. Join us next week for another episode.