Leading from Below

A new report coauthored by RMI finds that decarbonization is being led by states, cities, businesses, and other actors in the United States, while still noting that more action is needed. And how it put numbers on all this is part of the story.

By Dcpeopleandeventsof2017 - Own work, CC BY-SA 4.0,

By Christian Roselund
December 2019

As world leaders meet in Madrid for the COP25 summit, one issue looming over many of the discussions is the plans by the current US administration to withdraw from the Paris Accord in 2020. And while this is definitely a step back for the United States and global action on climate, the nation has long been something of an outlier in global climate agreements.

The United States was one of the few UN member states to never ratify the Kyoto Protocol, and it took until 2015 to rejoin the global community via participation in the Paris Agreement. As such, withdrawal from the Paris Accord can be seen as the federal government returning to its previous position.

But where the US federal government has failed to act, an increasingly broad and diverse coalition of cities, states, businesses, and others have stepped forward. Such leadership from states and other actors is also not new. While policies to address carbon emissions have floundered at the federal level, Iowa was the first state to require that utilities procure a portion of electricity from renewable sources in 1983, Hawaii became the first state to commit to a path to full decarbonization of electricity in 2015, and California has implemented a host of influential policies, from putting a price on carbon emissions to its “million solar roofs” program.

This leadership is also not confined to states; according to the Sierra Club, 140 US cities have committed to moving to 100 percent renewable electricity, with six more already having made the switch. More than 200 global companies have made similar commitments, and many of these have substantial operations in the United States.

Pushes to decarbonize—usually focused on the electricity sector—have particularly ramped up following the departure of the United States from the Paris Agreement. States, cities, businesses, universities, and other organizations have come together in various coalitions to affirm that even if the federal government has set a timeline to leave the Paris Agreement, the US people are still committed.

But while impressive, this local action is still resulting in a lesser level of emissions reductions than what could be expected with the help of bold federal policies.

Local vs. Federal

This dynamic of bottom-up leadership versus federal action is explored in the report Accelerating America’s Pledge, which is being presented tomorrow by US Presidential Candidate Mike Bloomberg, actor and environmentalist Harrison Ford, UNFCCC Executive Secretary Patricia Espinosa, and other officials at the COP25 conference. Rocky Mountain Institute (RMI) is a co-lead in the team which authored this report, which finds that a combination of public and private actors and the action of the market are together putting a big dent in emissions.

US emissions are already down 12 percent from 2005 levels, and the report projects that with all of the policies passed and actions committed to today, the nation’s emissions should be 25 percent below 2005 levels in 2030. This is in no small part due to all of the aforementioned commitments to decarbonizing electricity, but also through the market itself—notably the dismal economics of the nation’s aging coal-fired fleet.

But there’s a lot more potential than that. The America’s Pledge team finds that under a “bottom-up” scenario where leading non-federal actors intensify their ambition, emissions could be reduced 37 percent from 2005 levels by 2030.

Unpacking the Numbers

For any forecast it is essential to look closely at what scenario is being modeled, and for the 37 percent reductions this means a specific set of policies. What the report does not do is to prescribe policy approaches, and as such it doesn’t look at any radical new directions, only an intensification of what is already being done.

Policies modeled include measures such as implementation of mandates for utilities to procure 60 percent of their electricity from renewable energy by 2030 in leading states, which is currently the law in California. The report also assumes the shut-down of all coal plants in these “top-tier” states, and mandates that require new buildings to be all-electric. The latter requirement has already been implemented in more than a dozen cities in California and one in Massachusetts, but has yet to become policy at the state level.

Measures to reduce transportation emissions are also considered, and the bottom-up scenario models electric vehicles reaching two-thirds of new car sales and one-half of new truck sales by 2030. But due to the turnover times for the nation’s vehicle stock, the model only shows EVs reaching 18 percent of the vehicles on the road. And due to limited success in reducing vehicle miles traveled (VMT) to date, the team only forecast 2 percent reductions in VMT under the bottom-up scenario. The net result of these assumptions is that reductions in 2030 transportation emissions are limited compared to electricity sector reductions.

But measures were not limited to electricity and transportation, and the set of policies outlined under the “bottom-up” scenario include measures to improve energy efficiency in buildings, implement natural forest management, mitigate agricultural emissions, and greatly reduce methane emissions from oil and gas extraction.

One policy that is notably absent is a price on carbon. The report alludes to this on page 22: “This study demonstrates that the first half of deep decarbonization—through efforts that reduce energy bills—is feasible even without economy-wide carbon pricing, so progress does not need to wait for a change in the perceived politics of carbon pricing.”

Modeling the Future

But looking at the set of policies behind the 37 percent number only tells part of the story. To arrive at the specific level of reductions that this would achieve, it took reliable data, sophisticated software tools, and a team of 25 people.

The America’s Pledge analysis started with a set of baseline data from a wide variety of sources. These included energy and transportation data from the US Department of Energy (DOE), DOE’s National Renewable Energy Laboratory, the Department of Transportation, policy data from multiple organizations, and tools from other global nonprofit organizations.

The resulting policy impacts were modeled using ATHENA, a software tool designed for this sort of aggregation, which was developed by World Resources Institute as part of the America’s Pledge team, for its 2018 report and updated for the 2019 report.

“ATHENA is a new approach within modeling, because it is a tool to look at cities, states, and businesses all together, while others have just looked at one of them,” explains Carla Frisch, a principal who leads the RMI America’s Pledge team. A key advantage of ATHENA identified by the team is that it is designed to avoid double-counting, which is an inherent danger when looking at commitments by businesses and cities which overlap with each other and with state-level commitments.

In addition to this work with ATHENA, the team also conducted an economy-wide analysis using a US-specific version of the Global Change Assessment Model (GCAM). This not only provided baseline information for ATHENA, but the metrics arrived at through the ATHENA model were then fed back into GCAM for economy-wide analysis.

“There was a lot of work there to connect ATHENA and GCAM,” notes Frisch. “We’re really doing the math.”

Modeling is not limited to tools; it rests on assumptions and decisions about approaches. While scenarios by some of the world’s leading authorities on energy have been criticized as being detached from reality, the America’s Pledge team made an effort to base its forecasts on what is actually happening.

This is particularly notable for coal plant retirements. The team looked not only at the economics of coal-fired generation in competitive power markets, but also factored in political action. “Embedded in our assumptions, including and particularly for coal, is an engaged citizenship advocating for action,” states Frisch. “What we are looking at is what is actually happening on the ground. Coal plants are being retired, and citizens are being mobilized.”

At the same time, incorporated in the modeling is a recognition that some states might hold on to uneconomic coal plants for political reasons.

This is a very different approach from that taken by many of the organizations modeling the future of the power grid, which often start with a static assumption that current policies will remain frozen in time while the market evolves.

Federal Action Needed

The significant contributions of bottom-up action—both at current levels and with acceleration—is an important finding of Accelerating America’s Pledge. But it is important to note that even the enhanced state and local action modeled by the team will not reach the levels of decarbonization needed to stay below 1.5°C.

A third scenario modeled, “all-in”, looks at what would happen were federal leadership to expand on the other efforts modeled in the “bottom-up” scenario, with policies including a federal clean electricity standard, a complete phase-out of coal-fired power plants, and a federal requirement for new buildings to be all-electric.

In other words, it applies many of the policy actions of leading states in the bottom-up scenario to the entire nation, including the oil- and gas-producing states that are responsible for a large portion of US emissions and that have not been leaders on climate action.

In this scenario, America’s Pledge forecasts 49 percent emissions reductions from 2005 levels by 2030, in line with the goals of the Paris Agreement and the recent IPCC report on pathways to keep global warming below 1.5°C.

The central message of the report reflects the complexity of action at different levels in this time of urgency, with a decade left to put the world on a path to stay below 1.5°C. The actions of states, cities, businesses, and citizens has been and is meaningful in the race to decarbonize. But until the United States as a nation is fully committed, including with federal leadership, it is doubtful that we will be able to deliver on our nation’s share of the work to get off carbon and onto a path toward a safer future.