September 22, 2026

The ongoing impact of Princeton’s Net-Zero Initiative

By Victoria Cleave for Andlinger Center for Energy and the Environment

Rarely does a single academic study make an impact in congress, but Princeton’s 2020 Net-Zero America (NZA) report achieved that and more: it actively shaped major government decarbonization policies. The NZA study modeled and quantified five distinct scenarios through which the U.S. could decarbonize the entire economy using known technologies. It showed where power lines would need to be built, where solar energy installations, nuclear power, and wind farms would be most effective, how much it would all cost, and what needed to be done when to reach net-zero emissions by 2050. 

The timing of NZA helped to make substantial political waves, providing data and insight for breakthrough policies, but there have been substantial shifts in the federal policy landscape since its release. Nevertheless, the momentum generated by the unique approach of the study has not diminished: what began as a blueprint for domestic decarbonization has become a global framework for decarbonization decision support. By working with international researchers to launch targeted “Net-Zero X” (NZx) country studies and engaging with public and private sector stakeholders, the project is transforming how nations and corporations navigate the practical realities of the energy transition. 

Impact in the U.S.

The publication of NZA in 2020 generated widespread media coverage, and the authors extensively engaged with stakeholders across the U.S., giving over 300 briefings for federal and state executive and legislative bodies, environmental non-profits, private companies across energy, infrastructure, banking and other sectors, and the public. 

The study produced reactions as diverse as the many groups who viewed the results. For policymakers and politicians, it was a sobering view of the work that needs to be done to make a real impact on climate change; for companies, it was a chance to precisely understand what investments and on-the-ground changes it would take to adhere to pledges. For some, the scale of the challenge was overwhelming, but for others, it was a call-to-action.

“Ultimately our biggest impact was informing in a very direct way the Inflation Reduction Act of 2022 and to a lesser extent the Infrastructure Investment and Jobs Act of 2021,” says Eric Larson, one of three leaders on the study and a senior research scholar heading up the Energy Systems Analysis Group at the Andlinger Center for Energy and the Environment. “The NZA effort demonstrated the effectiveness of the study’s approach in providing actionable decision support.” 

This a bold manifestation of Princeton’s stated mission of civic service – not as an abstract ideal, but as a practical exercise magnified by the convening power of the Andlinger Center. The center’s focus on outreach and collaboration catalyzes profound research studies, but it also bypasses traditional insularities to bring together researchers, policymakers, and external partners to use those studies for real-world impact.

After the initial release, the NZA team worked to adapt to the needs of the ongoing political debate by inverting the output of the models: instead of showing the path to decarbonization, they used the work to show how far we would be from that path with different policies in place. Co-leader on the original NZA project, Jesse Jenkins, associate professor of mechanical and aerospace engineering and the Andlinger Center for Energy and the Environment, led this effort and focused his ZERO lab on developing the Rapid Energy Policy Evaluation and Analysis Toolkit (REPEAT). 

When new bills are introduced into congress there’s a short window of time for politicians to evaluate them and for journalists to try to understand and report their implications. Jenkins explains that the team managed to reduce analysis times using REPEAT to fit these windows, so they could produce rigorous independent evaluations in under a week to quantitatively ground the debate. 

“As policies were proposed by the Senate, the House, and the administration, we would produce quantitative analysis as quickly as possible to inform the debate at the speed of the debate, not the speed of academic publication,” he says.

A network of international partners

NZA established a model for generating actionable research. The team saw an opportunity to evolve and expand upon this approach through partnerships with international researchers to inform decarbonization debates in other countries.

While NZA provides the example and shows how such a study can have real world impact, each NZx project is a unique set up, with funding, research partners, and of course modeling parameters adapted to the circumstances and priorities of individual countries. Local collaborators with detailed cultural and environmental understanding lead each project. 

The Princeton team focused on launching NZx international collaborations first in countries where decarbonization could have the biggest impact: “We are committed to working with the biggest contributors to future emissions,” says Chris Greig, the Theodora D. ’78 & William H. Walton III ’74 Senior Research Scientist in the Andlinger Center for Energy and the Environment and the third leader of the NZA study. The project list has grown fast, and now consists of Net-Zero Australia, Net-Zero China, Net-Zero India, Net-Zero Korea, Net-Zero Poland, and Net-Zero Brazil. More projects are proposed or being initiated in Pakistan, Mexico, Indonesia, South Africa, and the Middle East and North Africa (MENA).

Each country brings its own set of unique criteria and challenges. India, for instance, with its massive population, is the third biggest greenhouse gas emitter in the world but ranks outside the top 100 countries in terms of emissions per capita. “With a developed country like the U.S., energy demands are already baked in: if you know population and gross domestic product growth there are a few surprises that come along like data centers, but these are trivial compared to a country like India,” says Greig. “Their future path on the demand side is extraordinarily uncertain.”

NZA used a single demand model: one trajectory with five different supply scenarios. “For NZ-India, the story is all about demand changes,” says Greig. “We use three distinct demand side scenarios: a climate mitigation scenario; a development scenario that focuses on human development, social welfare and economics; and a synergistic scenario that captures both the sustainability agenda and development.” 

Objectives for the projects in different countries can also vary. For instance, NZ-Brazil is focused on providing the widest possible access to the modeling tools so they can be used for decision making at all levels.

“Part of the objective of the NZ-Brazil team is to democratize by enabling people to run their own models, essentially,” says Larson. “When we put together the modeling machinery for NZA, we made all the input assumptions. Of course, we consulted with many stakeholders on these and documented everything, but we ultimately came out with a fixed set of scenarios.”

The NZ-Brazil team initially released an open-source online tool in early September 2026, ahead of the October presidential election in the country. “This tool allows anyone to rerun the models with their own inputs and get their own results,” says Larson. “That can include government policymakers and non-governmental stakeholders, which will make for better informed debates about the best paths forward for Brazil.”

Net-Zero Australia 

NZ-Australia was the first international project to launch, as a partnership between the Princeton team and researchers at The University of Queensland and The University of Melbourne. The project is now in its second phase, with the goal of translating modeling insights into specific actions to help accelerate the energy transition. They are undertaking more specific studies on issues like biodiversity and renewables, capital mobilization, infrastructure delivery, power system reliability, and energy security.

Like Net-Zero America, the NZ-Australia team have also found that their work has helped inform government policy and more. “We’ll talk to anybody at any time,” says Michael Brear, professor at The University of Melbourne and a member of the steering committee of NZ-Australia. “All sorts of people engage with the results, and overwhelmingly in a very enthusiastic way.”

On the government side, public servants, particularly Treasury, and the Prime Minister’s and other cabinet ministers’ departments apply the research to help understand potential returns on spending when projects are proposed. “The modeling helps government stakeholders understand what the significance of a given ask is in terms of its social or environmental outcomes,” says Brear.

Industrial decarbonization

While the most visible impacts of the Net-Zero Initiative have been in government policy influence both at home and abroad, the team also work extensively with U.S. and international corporations. Companies have the option of longer-term commitments than most governments, which is a key factor when it comes to decision-making on decarbonization. “We had a lot of conversations with the private sector because they were making pledges for their company; it informed corporations about what the future would need to look like to get to net-zero,” says Larson. 

Greig explains that the highly localized information that NZA provided can be used to a company’s advantage: where are renewables sited and where will future resources be, where is the carbon dioxide storage, where’s the best potential for hydrogen, where will there be workforce challenges, and so on. 

Most recently, the team have focused on the chemical industry as it’s considered among the most difficult emissions mitigation challenges and the largest driver of greenhouse gases amongst U.S. industries. “The model’s granularity lets us say things very specifically, for instance, in the Texas Gulf Coast region, the chemical industry is going to have to compete with X, Y, and Z for carbon storage capacity,” says Larson. 

Greig sees evidence in their partnerships that corporations have not necessarily lost interest in decarbonization with the recent federal shift in priorities, but that removing tax incentives and regulatory “pushes” makes the necessary capital allocation decisions much more difficult for them. 

“We’re still engaged with industry and particular sectors that realize that decarbonization is not going away. In the long term, the costs of the transition and the incremental system level costs are not that high; the problem is it can be very capital intensive in the short term,” he says. 

The future of Net-Zero 

Although a phase two of NZA is not currently planned, the team already have many ideas of what they would like to include if it happens in the future, starting with updating the reports with new data to see if 2050 is still feasible for net-zero in the U.S. now.

“The NZA study was focused on sustainability, decarbonization, and cost,” says Greig. “If I were to imagine NZA phase two in the coming years, it would have a stronger focus on the triple set of criteria around decarbonization: energy security, affordability, and a stronger recognition of the more detailed social and environmental conflicts and trade-offs that have to be navigated.” 

For the time being, however, the focus remains on the international NZx projects and finding partners in all sectors who are interested in pathways to decarbonization. A late-September workshop will bring 70 attendees to Princeton and the Andlinger Center from multiple NZx projects, aiming to foster collaboration and exchange between ongoing and prospective studies. As the initiative grows, more international researchers are approaching the team to request collaborations, and optimism remains about the fact that the desire to decarbonize doesn’t diminish overall, even if it ebbs and flows locally.

“I describe decarbonization as a global megatrend,” says Greig. “We have headwinds here right now and perhaps in 10 years’ time or five years’ time, we might have tailwinds. You have to prepare for both. You have to be able to accelerate when you have tailwinds and cope, survive, and compete when you have headwinds. But ultimately, that’s the path you’re on.”