In June 2015, leaders of seven of the world’s top economies—Germany, France, the United Kingdom, Italy, Japan, Canada, and the United States—gathered at the Schloss Elmau, a 1916 castle resort in the Alps of Upper Bavaria. These nations are the current members of the Group of 7, or G7. Jointly conceived by France and Germany in 1975, the G7 summit was first an opportunity for the world’s industrial leaders to discuss the global economy. Since then, the nations involved have changed (Canada was added; Russia was added and disinvited), and the issues have expanded to include foreign policy and security.

The Alpine resort where the leaders gathered is storybook beautiful. Nestled amidst snow-capped mountains, thick pine forests, and lushly grassed fields, the location provided an almost comical backdrop to the summit, as if the leaders had met for an exceptionally elite summer camp. As photos circulated, featuring the suit-clad group striding through fields topped with dandelion fuzz, the media couldn’t resist jokes about the location’s resemblance to The Sound of Music, the 1965 movie musical that features sweeping shots of the Austrian Alps.

“It’s easier to change several thousand power plants than millions of cars...”
Ines Azevedo, Associate Professor, һ

But above the idyllic scene, a threat was looming, a threat the assembled nations had, in part, come to address. Far above the cottony clouds, it lay over Bavaria like a suffocating blanket, wrapping everything under its purview—this clear mountain air, the salty expanse of the Pacific, the smog-filled city of Beijing—in one warm embrace.

The fibers of this all-encompassing blanket are made up of greenhouse gas emissions in the atmosphere. And one of these gases—carbon dioxide—is of particular concern. Since the industrial revolution that began in the latter half of the 18th century, levels of carbon dioxide emissions have been rising to historic heights, thanks to the burning of fossil fuels for industrial use, energy, and transportation. This unprecedented increase has brought with it a host of environmental threats: a gradually warming climate and, with it, an encroaching rise in sea levels and an increase in major weather events.

Global Warning

During this two-day summit, the G7 hopes to address this global threat. The effort is not only ideological; it is reparation for a shared history of CO2 emissions. The G7 participants alone are reported to be responsible for some 59 percent of the carbon dioxide emissions already in the atmosphere, a legacy of pollution that has touched every corner of the planet.

At the end of the two days, the G7 announced a commitment to reduce fossil fuel emissions by 40%-70% (as compared to 2010 levels) by the year 2050 and called for a complete elimination of fossil fuel emissions by the year 2100.

The numbers are hugely ambitious and, some might argue, largely symbolic. From an infrastructure standpoint, the changes necessary to meet these targets would have to be widespread and complete. From a policy standpoint, it will not be easy to gather the cooperation necessary for such a major overhaul of the system, especially not in the United States, where over half of the Republican faction in both the Senate and House deny that global warming is caused by human activity.

And yet, while the very premise of global warming is being questioned at the federal level, scientists have already started moving ahead with other questions: What are the options? How do we build a decarbonized world?

These questions are being examined with particular vigor at a university situated in the coal seat of Western Pennsylvania, in a region that is home to hotly contested and non-conventional natural gas drilling, in a city plagued by wastewater problems and a poor reputation for air quality. At a university named, in part, after the father of the American steel industry, Andrew Carnegie.

Hell with the Lid Off

The university is , and its home is Pittsburgh, a city built, literally, on fossil fuels. Pittsburgh’s metro area is situated on top of the Northern Appalachian Coal Basin, considered to be among the most valuable coal beds in the world. In combination with a three-river juncture and a rich deposit of natural gas, these coal reserves provided the foundation for a thriving industrial economy. At various points throughout the 19th and 20th centuries, Pittsburgh was a top producer of two heavy hitters in American industry (iron and steel) and the top refiner of a third (oil).

Pittsburgh was known as the “steel city.” But other nicknames were more pointed—“the smoky city” and, in the words of historian James Parton, “hell with the lid off.” The city’s dominance came at a price. But as Pittsburgh’s air suffered, the United States grew. Pittsburgh’s industry is visible in both the bones of the nation’s infrastructure and in the endowments of its cultural institutions. Libraries, parks, museums, and universities are branded by the names of the people who brought Pittsburgh’s industrial economy to its height. Carnegie, Frick, Mellon: names synonymous with the glory (and cash) of industry, and, thus, with fossil fuels.

Today, Pittsburgh has come far enough to wear its industrial history with a kind of pride. Since the steel industry collapsed in the 1970s, the city has refashioned itself. Now the economy is based on information and services—health care, technology, and finance. And though the city still has far to go, it is working to rebrand itself as a leader in environmental sustainability. In a discussion on moving away from fossil fuel dependence, Pittsburgh is a microcosm of the United States itself; it is a region that thrived on fossil fuels until it couldn’t.

The “couldn’t” is different in each case. In Pittsburgh, complaints about air quality existed (and were occasionally addressed) long before the collapse of the steel industry. But it was a confluence of economic factors (a market shift to the west, an influx of foreign competition, a general failure to modernize) that ultimately marked the end of the city’s industrial era. The United States faces a different quandary: Although economics play a role in whatever future is to come, the changing climate is forcing the nation’s collective hand.

“We have to decarbonize the electricity sector to decarbonize the transportation sector.”
Paulina Jaramillo, Assistant Professor, һ

And, oh, how that hand clings to fossil fuels. The United States is significantly dependent in the electricity and transportation sectors—on coal, natural gas, and petroleum. It’s a dependency the nation—if it is to listen to the G7’s (and its own) international call to action—must sever. And in mapping the course of the change, it seems appropriate to speak to the experts of Carnegie Mellon. Based in a city distinctively built on fossil fuels, they are now looking toward a fossil-fuel-free future, faculty members and researchers at the forefront of fields tied to climate change and decarbonization. And so we return to the questions:

What are the options? How do we build a decarbonized world?

To begin to answer, we must first look at the two U.S. sectors most dependent on fossil fuels: electricity and transportation. In the United States, transportation is more than 90% dependent on fossil fuel. Most consumers are already aware of the growing alternatives—biofuels, hydrogen, natural gas, and, most prominently and promisingly, hybrid and electric vehicles. But despite consumer familiarity, transportation is likely the second sector due for change. Ines Azevedo, an associate professor in Carnegie Mellon’s Department of and co-director of the , studies both the logistics and repercussions of energy systems. She looks beyond the solutions themselves to examine the results, in terms of policy feasibility, consumer behavior and total carbon emissions. To her, it is clear that the priorities for change need to be those that will be centralized and long lasting. To that end, “It’s easier to change several thousand power plants than millions of cars—though to solve the climate problem we will ultimately need to tackle both.”

And it’s not just a question of ease; it’s a question of efficacy. Azevedo points out that plugging a car in is not inherently much better than filling it with gasoline—at least, not if the electricity behind the plug is coming from coal. With the vast majority of the electricity in the United States—around 70%—powered by fossil fuels, your quiet, electric, gas-free car will be too, particularly if you power it at night, when coal-powered plants tend to come on the grid, which may actually result in carbon emissions similar to those of a gas guzzler. , an assistant professor of engineering and public policy and co-director of the , studies energy systems at both the engineering and public policy levels, incorporating social, economic, and environmental factors in her analysis. She explains that, in the chain of long-term change, electricity is the first domino: “We have to decarbonize the electricity sector to decarbonize the transportation sector.”

International Commitment

The electricity grid of the future will likely be made up of some combination of fossil fuels and more wind, solar, and nuclear. Wind, solar, and nuclear have only a minor role in the US power grid comes down to a simple point: money. Coal and natural gas are the two cheapest fuel sources we have. And by the logic of the current grid, they’ll always be on the front lines of power generation. When you turn on a light, the demand is processed by a regional power operator, which determines which power plant will be activated to supply the electricity. The primary factor in choosing which plant will be used is cost; the cheapest plants are used first. Coal and natural gas almost always win, mainly because we have a big infrastructure that is already in place and paid for. The secondary factor is time: how long does it take the plant to ramp up to the level at which it generates electricity? Nuclear plants, which constantly produce a base load of electricity, can not be easily ramped up and down to accommodate changes in demand. But this cost-centric system, Azevedo explains, makes it hard for wind and solar rarely make it into the mix, since this renewable infrastructure needs to be built. So while they cost little to operate, as there are no fuel costs, they may cost more to build since the fossil infrastructure is already in place. To overcome this and other issues of renewable integration, often renewables are treated as a “must-take” resource, which has been embedded in regulations for many power plants. This means that if a wind- or solar-powered plant is generating electricity, the electric grid must take that before it takes from anywhere else. It’s a small step toward ensuring that the electric grid is making use of the few renewables we already have on the map. But in the long term, and certainly to meet the G7 goal, it’s not enough.

We might also consider carbon capture, in which the carbon emissions of fossil fuels are contained and buried underground. Fossil-fueled energy would thus, ostensibly, lose its destructive aftereffects. But the technology, if it were to be developed (and were not prohibitively expensive), would only be delaying a still-inevitable task. Fossil fuels are finite, and though the fossil-fuel industry has been getting ever more creative in exploiting resources previously thought to be unobtainable or unusable, we will eventually have to stop using them altogether.

And in the current climate, “eventually” has to be put aside. One tactic to expedite the change, Azevedo explains, is an economic one: a price per ton of carbon dioxide emissions. In this model, the plants that used to be the cheapest—coal and natural gas—might now be the second cheapest, because of the price of their CO2 emissions. (Natural gas, though cleaner-burning than coal, nevertheless also lead to the release of some greenhouse gases into the atmosphere during the process of extraction and purification, combustion, and the whole attainment-to-use journey known as the fuel’s “life cycle.”) It’s an ingenious tactic, one that circumvents ideological arguments in favor of a price point. But putting a price on carbon and its effects, Azevedo explains, can become problematic. Can you put a dollar amount on the acidification of the oceans? On the rising sea level, on the subsequent loss of cities and coastlines? Even if we could find an agreed-upon price, another problem arises: carbon emissions cannot be contained by the regulations of one nation alone.

Carbon has a very long residence time in the atmosphere; once emitted, it lingers for some 100 years. , a professor of and director of the , studies the impact of airborne particulate matter in the atmosphere. Adams' work involves building simulations of the way particles enter, interact, and exit the atmosphere. By modeling theoretical emissions reductions, he can help determine what regulations would be most effective for improving air quality. His work intersects with climate change research, as fossil fuel use is an overlapping factor in the production of both particulate matter and CO2. Carbon emissions, Adams explains, are not bound by region; they disperse into the atmosphere at large, spreading out so that the amount of CO2 measured at any given point in the earth’s atmosphere is nearly identical. As a result, he explains, “the only fair and effective way to solve the carbon dioxide problem has to be very large scale. Global.” In a sense, this means that the G7 goal has a very practical importance; without the commitment of the international community, we can barely make a dent in CO2 emissions, and even if we were to act alone, we cannot insulate ourselves from the global atmosphere.

But the all-in-this-together attitude isn’t as warm and fuzzy as it might seem. , an associate research professor of engineering and public policy and the Executive Director of the , and the co-director of Carnegie Mellon’s , studies energy and environmental policy, including the life-cycle assessment and sustainability of various energy solutions. He explains that climate change is a generally difficult issue to confront—its long-term perspective, detailed analyses “only a statistician could fall in love with,” and an ability to recognize that intangibility should not be equated with innocuousness. Add to this the diffused responsibility of a worldwide issue, and you have a recipe for inertia. Things get even more complicated, Adams adds, when we consider the history of emissions. The majority of the carbon dioxide already in the atmosphere is the result of American and European industry. This is not lost on rapidly expanding nations like China and India, nations that, in comparing their own emissions history to the west’s, find that their impact on the environment has been less substantial. And in a sense, Adams explains, they feel entitled to catch up; to pollute as we’ve polluted. It’s the price, history would seem to tell us, of economic superiority.

Energy Access

For nations that are not growing in economic prosperity, an entirely different set of concerns arises. Part of Jaramillo’s research focuses on energy access and the 1.3 billion people around the world who do not have access to electricity. Directly tied to social and economic welfare, energy access is a profound priority worldwide and a need that requires major infrastructure development. Building this infrastructure without the use of (cheap) fossil fuels can seem nearly unimaginable. There is one potentially bright spot on the horizon; while economically advanced nations are being forced to update aging, polluting infrastructures, nations without these infrastructures in place have the opportunity to, in Jaramillo’s words, “leap-frog” to the renewable energy future we all seek. But the goal is not an easy or an inexpensive one, and Jaramillo is open about the fact that it may not be possible to provide energy access without the use of fossil fuels. “When a country is struggling to feed its population,” she explains, “worrying about climate change may not be a priority.”

We land again at a point of uncertainty. Some nations with highly developed economies are not willing to give up the fuels that allowed their G7 counterparts to rise to prosperity. And other nations, those without access to modern energy systems, will likely need some fossil fuel infrastructures if they are to thrive.

These conflicts alone would complicate international policymaking moving forward. But even in the United States, the waters are muddy. The country has often taken what Azevedo calls a “patchwork” approach to climate-change and energy policies, leading to regulations that differ vastly by region and cause inconsistencies in policy and practice. Griffin uses California as an example of this system-wide inefficiency. The state has low-carbon fuel standards that have encouraged the use of sugarcane ethanol, a fuel with low carbon impact. But this sugarcane ethanol is imported from Brazil. Brazil, in turn, doesn’t have enough ethanol to meet both its own needs and international demand. So the country imports ethanol from the Midwestern United States, ethanol that—due to its carbon intensity—cannot be used in California. From a transit standpoint alone, this system is wildly inefficient. “The system is leaking carbon,” Griffin explains. And unless the United States stops all fossil-fuel exports, which result from renewable energy use displacement, we will continue to release carbon emissions into the atmosphere, albeit through the infrastructure of another nation.

International policy would seem to be the only answer to this unique form of self-sabotage, and concrete change may be coming in this December’s . But even if we stopped all carbon emissions tomorrow, we would be dealing with the effects of climate change for decades to come. “There’s always a heritage,” says һ’s Richard S. Caliguiri University Professor of and a widely published expert on Pittsburgh’s industrial past. “A legacy,” he continues, “and the real question is, how do we reduce the legacy?”

In August, President Barack Obama addressed the nation about our collective environmental legacy, announcing . The plan lays out the first-ever nationwide standards to limit power-plant carbon emissions, requiring each state to design a plan for emissions reduction by 2018 and to start implementing the plan by 2022. The White House estimates the Clean Power Plan will result in a nationwide power-plant carbon-emissions reduction of 32% (as compared to 2005 rates) by 2030.

In comparison to the G7’s overarching goal, President Obama’s plan (if it withstands its inevitable challengers) seems almost pitifully small. But we have to acknowledge that, in this country, it is a revolutionary step.

And yet, as Tarr, Azevedo, Adams, Griffin, and Jaramillo ponder our environmental legacy, revolution seems like too dramatic a word. They are not anticipating a particularly sudden or sweeping change. Adams predicts that, like Moore’s Law, which states that computers get two times faster every year, change will happen gradually, as we follow a path that gets clearer by virtue of its length. Tarr points out that technology is fast, but regulation is slow; there tends to be a 50-year lag between the recognition of a problem and the beginning of a solution. Griffin has begun to think about adaptation, rather than mitigation; he is focusing his research on dealing with, rather than preventing, climate change.

Griffin’s pragmatism, it should be said, might be explained by his status as a native Pittsburgher. He remembers the collapse of the steel industry and the bleak hole left in its absence. He also remembers the city picking up and moving forward. To be clear, there was no vision of being a green city, no dreams of tech firms or film companies flocking to Pittsburgh neighborhoods. The city picked itself up because that’s what people do. Because, in Griffin’s words, “we made a conscious decision to survive.”