WORKING ON THE WORLDWIDE CLEAN ENERGY TRANSITION is not for the faint of heart. One moment there’s encouraging progress, the next brings reminders of the enormity of the task, looming deadlines, and the dire consequences of failure. The mood swings of faculty and researchers at the Kennedy School and across Harvard may best be summed up in the title of a recent talk at HKS given by the CEO of a clean power industry group: “The Future is Very Bright and Every Day is a Freaking Crisis.”

“The sheer scale of it is mind-boggling,” Harvard Vice Provost Jim Stock, director of the HKS-based Salata Institute for Climate and Sustainability at Harvard University, says of the task of transitioning the global economy from fossil fuels to sustainable sources of energy. In fact, economists say it will require the largest reallocation of capital in human history. While there has been recent good news in areas like economics—with renewable sources now often providing power cheaper than equivalent fossil fuels—major challenges persist on other fronts: geopolitical, technological, political, and more. 

Failure, meanwhile, is not an option. To avoid catastrophic consequences, the U.N.’s Intergovernmental Panel on Climate Change (IPCC) says the world community needs to reach its self-imposed goal of keeping global temperature rise below 1.5 degrees Celsius, the target adopted as part of the Paris Climate Agreement in 2015. Crossing that threshold risks unleashing severe climate change impacts, the IPCC says, including frequent and severe droughts, deadly heat waves, flood-inducing rainfall, and rising seas. “We have to get to net zero,” Stock says. “So we’re going to get there.” 

To meet the target, the IPCC says greenhouse gas emissions must peak by 2025 and decline 43% by 2030, which will require rapidly reducing fossil-fueled power, in favor of carbon-free energy sources like wind, solar, hydro, and geothermal. Across HKS, faculty, researchers, staff, and students are collaborating with others across Harvard, at other institutions, and around the world to understand and embrace the challenges and, hopefully, overcome them while there is still time. 

Geopolitical Opportunities and Challenges

With a worldwide infrastructure transition, you get global-sized challenges—but also opportunities. 

In fact, the green energy transition may be the greatest opportunity that developing countries will have for foreign investment and for economic growth, says Ricardo Hausmann, the founder and director of Harvard’s Growth Lab and the Rafik Hariri Professor of the Practice of International Political Economy. In an HKS Executive Education class called “Leading Green Growth,” Hausmann and Professor Daniel Schrag like to paraphrase President John F. Kennedy when summing up a key part of their philosophy: “Ask not what to do to decarbonize yourself. Ask what you can do to decarbonize the world.” A world that wants to decarbonize will need many things that will enable it to do so. They say policymakers should focus on how their countries can supply these enabling technologies, rather than just focusing on cutting their own emissions. “Right now the discourse to developing countries is: ‘We know you were unsuccessfully trying to grow, but now you’ll have to try to do it with additional constraints—even though you may not have contributed much to the climate problem,’” Hausmann says. “I find that frame unhelpful.” 

Hausmann points to Bolivia, South America’s second-poorest country. It is counterproductive to focus on lowering Bolivia’s emissions, he says, when it has the largest lithium reserves in the world—from which it has yet to extract the first ton. Hausmann says worldwide decarbonization requires everything from batteries, which currently use lithium, to wind turbines to solar panels to fuel cells to EVs and more, so for developing countries the questions should be: “Where in those value chains can you participate?” 

He also says that so-called “powershoring”—moving energy-intensive industries closer to where clean power is being generated—is a potential growth boon for developing countries. Since green energy is mostly electricity, which is becoming cheaper but is less transportable, it will be more cost-effective to relocate industries such as steelmaking, chemical processing, and cement manufacturing than to bring power to where they are now. 

Portrait of Ricardo Hausmann

“Right now we’re saying to them: ‘We know you were trying to grow, but now you’ll have to grow with some constraints— even though you may not have contributed a lot to the problem.’ I find that frame unhelpful.”

Ricardo Hausmann

That opens opportunities for countries with large solar reserves such as Morocco, Namibia, and Chile, he says, and ones with large hydropower reserves like Brazil, Paraguay, and Venezuela. Hausmann says the Growth Lab is now working in Morocco, which has a state-owned fertilizer enterprise called OCP that exploits some of the world’s largest phosphate mines. Since, in addition to phosphate, fertilizer also requires ammonia, OCP currently imports it from countries that make it from natural gas, a high-emitting process. But OCP is planning to use Morocco’s sun and wind to locally manufacture 1 million tons of ammonia a year—about a third of their production needs.

Yet the success of scenarios like the ones Hausmann has outlined will depend on a favorable geopolitical environment. That is not assured, says Meghan O’Sullivan, the Jeane Kirkpatrick Professor of the Practice of International Affairs and faculty director of the Belfer Center for Science and International Affairs.

In the case of Bolivia’s lithium reserves, for example, the country last year signed an extraction agreement with a Chinese consortium—one of many international deals China has signed with countries that possess minerals critical to green technology like lithium and cobalt. China’s dominance in the mining and processing of those critical metals has exacerbated its great power rivalry with the United States and is a potential bottleneck to adoption of green technology, says O’Sullivan, who also directs the Geopolitics of Energy Project at HKS.

“Right now we see a big effort to recreate those supply chains outside of China so that they’re not susceptible to geopolitical hiccups,” she said, during a recent talk on the geopolitics of energy. “That of course means that all of those inputs into clean energy are going to be more expensive and that it’s going to take longer to do.” 

Portrait of Meghan O’Sullivan

“We need to think more about how we can harness great power competition and use that in crafting a strategy that can advance the objective of getting to net zero.”

Meghan O’Sullivan

O’Sullivan says the green energy transition and geopolitics are closely connected, in a way where each influences the other. Russia, for example, responded to economic sanctions over its invasion of Ukraine by cutting off gas supplies to European countries, which responded by importing more coal and subsidizing $1 trillion in fossil energy to consumers. “These are two things you don’t want to do if you’re trying to make a clean energy transition,” she says. Meanwhile, China has also purchased Russian energy as Russian President Vladimir Putin and Chinese President Xi Jinping move to create a new geopolitical order that minimizes the power of the United States—undermining global institutions working to promote the clean energy future in the process, she says. 

But China, which has had major problems with poor air quality, has also invested heavily in domestic clean power, especially solar, says the Belfer Center’s Venkatesh “Venky” Narayanamurti, the Benjamin Peirce Professor of Technology and Public Policy, Engineering and Applied Sciences, and Physics, Emeritus. In a recent paper highlighting successes among emerging economies in transitioning to green power, Narayanamurti and two co-authors said China added 158 gigawatts of solar power—equivalent to the total power generating capacity of Brazil—between 2014 and 2018 alone. Yet it is also sitting on 100 years of coal reserves, he says, “so it is still a question of economic development, because coal is cheap.” 

Which direction China will go—toward a clean energy future and domestic energy security or a fossil fuel future that maintains its geostrategic alliance with Russia—will have major implications for both the climate crisis and geopolitics, O’Sullivan says. “We need to think more about how we can harness great power competition and use that in crafting a strategy that can advance the objective of getting to net zero,” she says.

 An illustration depicting solar panels reflecting a landscape with a road on which a large semi-truck is following an electric vehicle.


Complex Economics

China is also an X-factor in the economics of the clean energy transition. The country was once forecasted to surpass the U.S. economy as the world’s largest by 2030, but now many economists say that may never happen, due to its aging workforce, declining population, and recent debt-driven real estate bust. “I think it has a couple of immediate impacts in terms of what the emissions profile looks like in China and then what that means in terms of global impact,” says economist Joe Aldy, the Teresa and John Heinz Professor of the Practice of Environmental Policy and faculty director of the Regulatory Policy Program at the Mossavar-Rahmani Center for Business and Government

Economists see China’s slowdown as a double-edged sword. A 2023 report released by the International Energy Agency found that even a 1% further drop in the country’s growth rate would reduce 2030 coal demand by an amount equivalent to the coal consumed by all of Europe. At the same time, China dominates the strategic minerals market and produces 60% of the world’s electric cars, 45% of its solar technology, and 30% of new nuclear capacity, meaning an economic slowdown could impact international supply chains for clean energy technology, the report states.

Yet China’s mass production of solar panels combined with government subsidies for solar projects in countries like the United States has already helped power irreversible change in the economics of energy around the world, Aldy says. “Once you’ve made solar panels cheap … they’re not going to get expensive again,” he said during a recent episode of the HKS PolicyCast podcast.

Portrait of Joe Aldy

“The Inflation Reduction Act will probably cut our emissions to about 40% below 2005 levels by 2030, which is a stunning change in the trajectory of emissions.”

Joe Aldy

HKS Assistant Professor Charles Taylor, who researches the environment, agriculture, and climate change, says the relative costs for solar and wind power versus fossil fuels have flipped in half a decade. “From 2018 to 2023, the United States went from coal producing five times the amount of electricity as wind and solar combined, to just this past year wind and solar surpassing coal,” Taylor says. “The power projects being developed today are almost all wind and solar—outside of some gas, almost no new fossil projects are getting built.” But even the good news on clean power generation is tempered by another variable: the cost of upgrading the U.S. power grid to handle new electrical capacity, including clean power generation and battery storage. In Washington, the recently passed Inflation Reduction Act and the Bipartisan Infrastructure Law added $23 billion to the $300 billion already being invested annually in upgrading the grid.

But the International Energy Agency estimates that yearly spending will need to rise to $600 billion per year by 2030 if the U.S. grid is to keep pace. Cost issues also factor into other technologies being touted as potential solutions to the climate crisis. In a recent paper, Mohammed Al-Juaied, a research associate at the Belfer Center’s Environment and Natural Resources Program, found that the technology for direct air carbon capture and storage (DACCS) will cost “trillions” of dollars and take several decades to reach the level of removing one gigaton—one billion metric tons—per year, even in the most optimistic scenarios. (Current annual worldwide carbon emissions are just under 37 gigatons.)

Political Challenges

The task of upgrading energy grids also illustrates the political challenges facing the clean energy transition. While it can take anywhere from one to five years to bring a solar or wind energy generation project online, permitting and building new transmission infrastructure can take as long as five to 15 years. Portions of those delays stem from permitting processes that give local residents and governments significant power to block or delay projects, Charles Taylor says. In recent years, tensions have grown even between climate activists and old-school conservationists, who often oppose clean energy projects proposed for natural areas, and Taylor says permitting reform is needed to balance ecological concerns with the need to get projects built quickly. 

Climate crisis responses at the national level also hang in the balance. With Democrats controlling the House and Senate, President Joe Biden reaffirmed the United States’ commitment to the Paris Agreement and pushed through the Inflation Reduction Act of 2022, the first major American climate bill. “The Inflation Reduction Act will probably cut our emissions to about 40% below 2005 levels by 2030, which is a stunning change in the trajectory of emissions,” says Aldy. “If you look before 2009, the only times U.S. emissions fell year-on-year was during a major recession.” 

Portrait of Gordon Hanson

“If you look at any other kind of major technology transition that the world has undergone in the last 100 years, it’s rare one country is able to generate all of the technology it needs on its own.”

Gordon Hanson

The Inflation Reduction Act also includes provisions that much of the clean energy technology it funds must be developed in the United States. That boosted the bill’s popularity among domestic lawmakers, but some scholars say it may not be the best approach. “If you look at any other kind of major technology transition that the world has undergone in the last 100 years, it’s rare one country is able to generate all of the technology it needs on its own,” says Gordon Hanson, the Peter Wertheim Professor in Urban Policy. In a recent paper he co-authored, Hanson makes the case for what he calls a “Green Free Trade” agreement that would be established under the auspices of the World Trade Organization. 

Meanwhile, Republicans took control of the House in 2023, and House Speaker Mike Johnson of Louisiana has already pushed a House bill that would cut funding for renewables provided by the Inflation Reduction Act. And Robert Stavins, the A.J. Meyer Professor of Energy and Economic Development and director of the Harvard Environmental Economics Program and the Harvard Project on Climate Agreements, says America’s polarized politics make it nearly impossible to adopt more controversial yet vital policies like fuel and carbon taxes. “If one of the ways you increase energy prices or increase carbon prices is through political action, then politics in the United States is a major barrier,” he says.

​​​​​​This is an illustration of a mobile that resembles a wind chime and features symbols of clean energy transition.

Mitigating the Effects

Climate scholars live in a world that alternates between optimism and pessimism. Aldy says he doesn’t know many experts who still think global warming will be held below the key 1.5 degrees Celsius target. Taylor points to the fact that, thanks to advances in worldwide clean energy, experts say “truly terrifying” warming scenarios like 5 degrees are increasingly unlikely. 

In between lies an era that climate modelers call “climate overshoot”—where warming exceeds optimal levels for years or even decades but is brought back down again as fossil fuels are phased out in favor of clean energy sources. What virtually everyone agrees on, is that during this period, steps must be taken to mitigate climate change’s impact on humanity. “It’s going to be important for us to think about adaptation, about loss and damage for those most vulnerable around the world, and even other novel interventions on climate like solar geoengineering,” Aldy says.

Several initiatives are underway in this area at HKS and Harvard, including research clusters at the Salata Institute that bring together scholars from various disciplines across the University, director Jim Stock says. The Climate Adaptation in South Asia cluster includes Professor Daniel Schrag, director of the Belfer Center’s Science, Technology, and Public Policy Program, as well as scholars and researchers from the T.H. Chan School of Public Health, Harvard Medical School, Harvard Business School, and the Faculty of Arts and Sciences. Adaptation is a major issue in countries like India, where health experts say extreme heat events in some regions are now approaching the limits of human survivability, and the Maldives, where the World Bank estimates that sea level rise threatens to make 80% of the country uninhabitable by 2050. A second adaptation research cluster focuses on the Gulf of Guinea, where sea levels are expected to affect millions of coastal residents of eight African countries. 

Portrait of Robert Stavins

“If one of the ways you increase energy prices or increase carbon prices is through political action, then politics in the United States is a major barrier.”

Robert Stavins

Meanwhile, the Strengthening Communities research cluster works at the community level—in places ranging from traditional energy-rich regions to agricultural communities to fisheries—to help local leaders and citizens understand both the social costs and the benefits of the clean energy transition, Stock says. “They need to know that they have a way to benefit from it, and that benefit really filters down to an individual level, so that people see this as a valid trade,” he says.

Gordon Hanson’s work also focuses on helping communities successfully navigate the clean energy transition, especially when it comes to jobs and employment, through the Reimagining the Economy project, which he co-directs with Dani Rodrik, the Ford Foundation Professor of International Political Economy. They estimate the clean energy transition will directly affect approximately 1 million workers in core fossil fuel jobs like drilling, mining, refining, and distribution, and as many as 800,000 workers in energy-intensive industries such as metal, paper, and chemical manufacturing that are usually located close to power generation sources. Hanson’s policy recommendations include separating climate policy from the efforts to help distressed economic regions and expanding the scale of labor market retraining programs that help displaced workers get re-employed quickly. 

“We’ve learned a lot about what works,” Hanson says. “What we haven’t done yet is scale those approaches or deploy information about how to implement them nationally.”

Moving Forward

One important priority during the climate overshoot era will be buying time for the technological advancements and infrastructure changes necessary for the clean energy transition to move forward. Stavins says one way to achieve that is to reduce the amounts of methane in the atmosphere, which is a major priority for HKS and the Salata Institute, where he is the principal investigator for the Reducing Global Methane Emissions research cluster.

“Methane is a very, very potent greenhouse gas, and if we’re thinking about the next 10 years or 15 years … it stands out as being vastly more important than CO2,” he says. While carbon dioxide can stay in the atmosphere for a century or more, Stavins says, methane breaks down in 12 to 18 years, so efforts to reduce it can have a dramatic short-term effect on slowing temperature rise. “Since the pledges under the Paris Agreement are for the year 2030, which is now just six years off, it’s very important to think about the short term.”

The Paris Agreement was adopted at the 21st United Nations climate conference (also known as the Conference of the Parties or COP). Stavins, who with Stock led a major Harvard delegation to COP28 in Dubai in December, says many people and media outlets misunderstand what the conference does. “People should not anticipate that there is this global government that makes decisions that then filter down,” Stavins says. Instead, national delegations meet to discuss and update their individual country’s voluntary plans to cut emissions (known as Nationally Determined Contributions or NDCs). 

Portrait of Kathryn Sikkink

“Litigation is one tool that we use together with many, many other tools that we need to bring about climate justice and to have a healthier future.”

Kathryn Sikkink

While NDCs are not enforceable under international law, Kathryn Sikkink, the Ryan Family Professor of Human Rights Policy at HKS, says they have created a legal path for citizen plaintiffs—especially young climate activists—to turn the climate crisis into a rights issue in national courts. When they win, the activists can “put some teeth” into their country’s climate pledges and hold their own governments accountable, she says. In a case brought by the environmental group Urgenda and 900 citizens who cited the Dutch constitution and various international human rights agreements, for example, the highest court in the Netherlands upheld a decision forcing the government to increase its emissions reduction target from 20% below 1990 levels to 25% by the end of 2020. Similar cases have been brought in Colombia, Germany and by a group of young people in Montana.

“Litigation is one tool that we use together with many, many other tools that we need to bring about climate justice and to have a healthier future,” Sikkink says. 

Stavins says he considers COP28 a qualified success. While much of the post-event media coverage focused on the language of the closing statement, he said most of the important work at COP meetings now takes place outside the formal negotiations. Recent COP meetings have evolved into what Stavins fondly calls a sort of “climate expo,” where people working on climate in various ways meet to exchange ideas and plan collaborations and where the roles of universities, NGOs, and private industry are more important.

The sizable Harvard COP28 delegation hosted a major event showcasing the research and policy work being done at HKS and across Harvard (under the auspices of the Salata Institute) on methane emissions and held more than two dozen bilateral meetings with various country delegations, environmental organizations, industry groups, corporations, and the media, Stavins said. While their current work on methane focuses on the oil and gas sector in the United States, they plan to expand to other sources worldwide including livestock, rice production, and landfills.

Looking to the future, Stavins says he’s hopeful, but pragmatic.

“I am cautiously optimistic,” he says. “But I do recognize that what’s happened up until now has not put the countries of the world, including the European Union and the United States, on the trajectory that many people want. We’re not going to be able to limit warming to 1.5 degrees—that’s just not happening.”

Stavins says that if he does allow himself any “unbridled optimism,” it’s not from developments in technology, geopolitics, or economics, but from observing today’s youth infuse their passion into the clean energy transition. “Young people are so much more engaged in this issue,” he says. “When I was their age, it was the Vietnam War. Now it’s climate advocacy.”

Illustrations by Grace J. Kim. Photographs by Martha Stewart.

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