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New rules governing how companies report their scope 2 emissions have pit tech giant against tech giant and scholars against each other.

All summer, as the repeal of wind and solar tax credits and the surging power demands of data centers captured the spotlight, a more obscure but equally significant clean energy fight was unfolding in the background. Sustainability executives, academics, and carbon accounting experts have been sparring for months over how businesses should measure their electricity emissions.
The outcome could be just as consequential for shaping renewable energy markets and cleaning up the power grid as the aforementioned subsidies — perhaps even more so because those subsidies are going away. It will influence where and how — and potentially even whether — companies continue to voluntarily invest in clean energy. It has pitted tech heavyweights like Google and Microsoft against peers Meta and Amazon, all of which are racing each other to power their artificial intelligence operations without abandoning their sustainability commitments. And it could affect the pace of emissions reductions for decades to come.
In essence, the fight is over how to appraise the climate benefits of companies’ clean power purchases. The arena is the Greenhouse Gas Protocol, a nonprofit that creates voluntary emissions reporting standards. Companies use these standards to calculate emissions from their direct operations, from the electricity and gas that powers and heats their buildings, and from their supply chains. If you’ve ever seen a brand claim it “runs on 100% renewable energy,” that statement is likely backed by a Greenhouse Gas Protocol-sanctioned methodology.
For years, however, critics have poked holes in the group’s accounting rules and assumptions, charging it with enabling greenwashing. In response, the organization has decided to overhaul its standards, including for how companies should measure their electricity footprint, known as “scope 2” emissions.
The Greenhouse Gas Protocol first convened a technical working group to revise its Scope 2 Standard last September. By late June, the group had finalized a draft proposal with more rigorous criteria for clean energy claims, despite intense pushback on the underlying direction from companies and clean energy groups.
A flurry of op-eds, essays, and LinkedIn posts accused the working group of being on the “wrong track,” and called the proposal a “disaster” with “unintended consequences.” The Clean Energy Buyers Association, a trade group, penned a letter saying it was “inefficient and infeasible for most buyers and may curtail ambitious global climate action.” Similarly, the American Council on Renewable Energy warned that the plan “could unintentionally chill investment and growth in the clean energy sector.”
Next the draft will face a 60-day public consultation period that begins in early October. “There’ll be pushback from every direction,” Matthew Brander, a professor of carbon accounting at the University of Edinburgh and a member of the Scope 2 Working Group, told me. Ultimately, it will be up to the Working Group, the Protocol’s Independent Standards Board, and its Steering Committee, to decide whether the proposal will be adopted or significantly revised.
The challenge of creating a defensible standard begins with the fundamental physics of electricity. On the power grid, electrons from coal- and natural gas-fired power plants intermingle with those from wind and solar farms. There’s no way for companies hooking up to the grid to choose which electrons get delivered to their doors or opt out of certain resources. So if they want to reduce their carbon footprints, they can either decrease their energy consumption — by making their operations more efficient, say, or installing on-site solar panels — or they can turn to financial instruments such as renewable energy certificates, or RECs.
In general, a REC certifies that one megawatt-hour of clean power was generated, at some point, somewhere. The current Scope 2 Standard treats all RECs as interchangeable, but in reality, some RECs are far more effective than others at reducing emissions. The question now is how to improve the standard to account for these differences.
“There is no absolute truth,” Wilson Ricks, an engineering postdoctoral researcher at Princeton University and working group member, told me back in June. “I mean, there are more or less absolute truths about things like how much emissions are going into the atmosphere. But the system for how companies report a certain number, and what they’re able to claim about that number, is ultimately up to us.”
The current standard, finalized in 2015, instructs companies to report two numbers for their scope 2 emissions, based on two different methodologies. The formula for the first is straightforward: multiply the amount of electricity your facilities consume in a given year by the average emissions produced by the local power grids where you operate. This “location-based” number is a decent approximation of the carbon emitted as a result of the company’s actual energy use.
If the company buys RECs or similar market-based instruments, it can also calculate its “market-based” emissions. Under the 2015 standard, if a company consumed 100 megawatt-hours in a year and bought 100 megawatt-hours’ worth of certificates from a solar farm, it could report that its scope 2 emissions, under the market-based method, were zero. This is what enables companies to claim they “run on 100% renewable energy.”
RECs are fundamentally different from carbon offsets, in that they do not certify that any specific amount of emissions has been prevented. They can cut carbon indirectly by creating an additional revenue stream for renewable energy projects. But when a company buys RECs from a solar project in California, where the grid is saturated with solar, it will do less to reduce emissions than if it bought RECs from a solar project in Wyoming, where the grid is still largely powered by coal, or from a battery storage project in California, which can produce clean power at night.
There are other ways RECs can vary — for instance, companies can buy them directly from power producers by means of a long-term contract, or as one-off purchases on the spot market. Spot market REC purchases are generally less effective at displacing fossil fuels because they’re more likely to come from pre-existing wind and solar farms — sometimes ones that have been operating for years and would continue with or without REC sales. Long-term contracts, by contrast, can help get new clean energy projects financed because the guaranteed revenue helps developers secure financing. (There are exceptions to these rules, but these are broadly the dynamics.)
All this is to say that the current standard allows for two companies that consumed the same amount of power and bought the same number of RECs to report that they have “zero emissions,” even if one helped reduce emissions by a lot and the other did little to nothing. Almost everyone agrees the situation can be improved. The question is how.
The proposal set for public comment next month introduces more granularity to the rules around RECs. Instead of tallying up annual aggregate energy use, companies would have to tally it up by hour and location. To lower companies' scope 2 footprints further, purchased RECs will have to be generated within the same grid region as the company’s operations, and match a distinct hour of consumption. (This “hourly matching” approach may sound familiar to anyone who followed the fight over the green hydrogen tax credit rules.)
Proponents see this as a way to make companies’ claims more credible — businesses would no longer be able to say they were using solar power at night, or wind power generated in Texas to supply a factory in Maine. While companies would still not be literally consuming the power from the RECs they buy, it would at least be theoretically possible that they could be. “It’s really, in my view, taking how we do electricity accounting back to some fundamentals of how the power system itself works,” Killian Daly, executive director of the nonprofit EnergyTag, which advocates for hourly matching, told me.
The granularity camp also argues that these rules create better incentives. Today, companies mostly buy solar RECs because they’re cheap and abundant. But solar alone can’t get us to zero emissions electricity, Ricks told me. Hourly matching will force companies to consider signing contracts with energy storage and geothermal projects, for example, or reducing their energy use during times when there’s less clean energy available. “It incentivizes the actions and investments in the technologies and business practices that will be needed to actually finish the job of decarbonizing grids,” he said.
While the standard is technically voluntary, companies that object to the revision will likely be stuck with it, as governments in California and Europe have started to integrate the Greenhouse Gas Protocol’s methodologies into their mandatory corporate disclosure rules.
The proposal’s critics, however, contend that time and location matching will be so costly and difficult to implement that it may lead companies to simply stop buying clean energy. One analysis by the electricity data science nonprofit WattTime found that the draft revision could increase emissions compared to the status quo if it causes a decline in corporate clean power procurement. “We’re looking at a potentially really catastrophic failure of the renewable energy market,” Gavin McCormick, the co-founder and executive director of WattTime, told me.
Another concern is that companies with operations in multiple regions could shift from signing long-term contracts for RECs, often called power purchase agreements, to relying on the spot market. These contracts must be large to be beneficial for developers because negotiating multiple offtake agreements for a single renewable energy project increases costs and risk. Such deals may still make sense for big energy users like data centers, but a company like Starbucks, with cafes throughout the country, will have to start sourcing fewer RECs in more places to cover all the parts of the world where they operate.
The granularity fans assert that their proposal will not be as challenging or expensive as critics claim — and regardless, they argue, real decarbonization is difficult. It should be hard for companies to make bold claims like saying they are 100% clean, Daly told me. “We need to get to a place where companies can be celebrated for being like, I’m not 100% matched, but I will be in five years,” he said.
The proposal does include carve-outs allowing smaller companies to continue to use annual matching and for legacy clean energy contracts, even if they don’t meet hourly or location requirements. But critics like McCormick argue that the whole point of revising the standard is to help catalyze greater emission reductions. Less participation in the market would hurt that goal — but more than that, these accounting rules aren’t designed to measure emissions, let alone maximize real-world emission reductions. You could still have one company that spends the time and money to invest in scarce resources at odd hours and achieves 60% clean power, while another achieves the same proportion by continuing to buy abundant solar RECs. Both would still get to claim the same sustainability laurels.
The biggest corporate defender of time and location matching is Google. On the other side are tech giants Meta and Amazon, among others, arguing for an approach more explicitly focused on emissions. They want the Greenhouse Gas Protocol to endorse a different accounting scheme that measures the fossil fuel emissions displaced by a given clean energy purchase and allows companies to subtract that amount from their total scope 2 footprint — much more akin to the way carbon offsets work.
If done right, this method would recognize the difference between a solar REC in California and one in Wyoming. It would give companies more flexibility, potentially deploying capital to less developed parts of the world that need help to decarbonize. It could also, eventually, encourage investment in less mature and therefore more expensive resources, like energy storage and geothermal — although perhaps not until there’s solar panels on every corner of the globe.
This idea, too, is risky. Calculating the real-world emissions impact of a REC, which the scope 2 working group calls “consequential accounting” is an exercise in counterfactuals. It requires making assumptions about what the world would have looked like if the REC hadn’t been purchased, both in the near term and long term. Would the clean energy have been generated anyway?
McCormick, who is a proponent of this emissions-focused approach, argues that it’s possible to measure the counterfactual in the electricity market with greater certainty than with something like forestry carbon offsets. With electricity, he told me, “there's five minute-level data for almost every power plant in the world, as opposed to forests. If you're lucky, you measure some forests, once a year. It's like a factor of 10,000 times more data, so all the models are more accurate.”
Some granularity proponents, including Ricks, agree that consequential accounting is valuable and could have a place in corporate reporting, but worry that it’s ripe for abuse. “At the end of the day, you can't ever verify whether the system you're using to assign a given company a given number is right, because you can't observe that counterfactual world,” he said. “We need to be very cautious about how it’s designed, and also how companies actually report what they’re doing and what level of confidence is communicated.”
Both proposals are flawed, and both have potential to allow at least some companies to claim progress on paper while having little real-world impact. In some ways, the disagreement is more philosophical than scientific. What should this standard be trying to achieve? Should it be steering corporate dollars into clean energy, accuracy of claims be damned? Or should it be protecting companies from accusations of greenwashing? What impacts do we care about more, faster emissions reductions or strategic decarbonization?
“They’re actually not opposing views,” McCormick told me. “There’s these people making this point and there’s these people making this point. They’re running into each other, but they’re actually not saying opposite things.”
To Michael Gillenwater, executive director of the Greenhouse Gas Management Institute, a carbon accounting research and training nonprofit, people are attempting to hide policy questions within the logic and principles of accounting. “We’re asking the emissions inventories to do too much — to do more than they can — and therefore we end up with a mess,” he told me. Corporate disclosures serve many different purposes — helping investors assess risk, informing a company’s internal target setting and performance tracking, creating transparency for consumers. “A corporate inventory might be one little piece of that puzzle,” he said.
Gillenwater is among those that think the working group’s time- and location-matching proposal would stifle corporate investment in clean energy when the goal should be to foster it. But his preferred solution is to forget trying to come up with a single metric and to encourage companies to make multiple disclosures. Companies could publish their location-based greenhouse gas inventory and then use market-based accounting to make a separate “mitigation intervention statement.” To sum it up, Gillenwater said, “keep the emissions inventory clean.”
The risk there is that the public — or indeed anyone not deeply versed in these nuances — will not understand the difference. That’s why Brander, the Edinburgh professor, argues that regardless of how it all shakes out, the Greenhouse Gas Protocol itself needs to provide more explicit guidance on what these numbers mean and how companies are allowed to talk about them.
“At the moment, the current proposals don’t include any text on how to interpret the numbers,” he said. “It’s almost incredible, really, for an accounting standard to say, here’s a number, but we’re not going to tell you how to interpret it. It’s really problematic.”
All this pushback may prompt changes. After the upcoming comment period closes in late November or early December, the working group could decide to revise the proposal and send it out for public consultation again. The entire revision process isn’t estimated to be completed until the end of 2027 at the earliest.
With wind and solar tax credits scheduled to sunset around then, voluntary action by companies will take on even greater importance in shaping the clean energy transition. While in theory, the Greenhouse Gas Protocol solely develops accounting rules and does not force companies to take any particular action, it’s undeniable that its decisions will set the stage for the next chapter of decarbonization. That chapter could either be about solving for round-the-clock clean power, or just trying to keep corporate clean energy investment flowing and growing, hopefully with higher integrity.
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On ‘modernizing’ coal, 2.8 degrees of warming, and Spain’s nuclear phaseout
Current conditions: Hurricane Melissa passed by Bermuda on its way northward, leaving at least 30 dead in its wake across the Caribbean • Tropical Storm Kalmaegi is strengthening as it approaches the eastern shore of the Philippines • Colombia and Venezuela are bracing for flooding from heavy rainfall up to 2 inches above average.
The Environmental Protection Agency has quietly walked back its plans to eliminate Energy Star, the popular program that costs just $32 million in annual budget but saves Americans more than $40 billion each year. In May, EPA Administrator Lee Zeldin announced that his agency would end the program. The proposal drew swift backlash from industry groups and Republicans in Congress, as I wrote in a July newsletter. Now Zeldin is reconsidering the move, four unnamed sources with direct knowledge of the agency’s plans told The New York Times. Federal records show the agency renewed four contracts with ICF, the consulting firm that helps oversee the program, including one deal that stretches through September 2030.
Calling the initial plan to eliminate Energy Star “vexing,” RE Tech Advisors’ Deb Cloutier, one of Energy Star’s original architects, told Heatmap’s Jeva Lange, “There are a lot of lobbying efforts that I’m personally aware of within the commercial real estate industry and the manufacturing industry, where folks are reaching out and doing calls to action for the House and Senate Appropriations majority members — similar activities to what we did eight years ago when Energy Star was directly under fire.” She added, “I know that there are many, many representatives, both Republican and Democrats, who support Energy Star. We’ve had 35 years of bipartisan support, and it has been earmarked in congressional law many times, through multiple George H.W. and George W. Bush administrations.”
The world is on track to warm by an average of 2.8 degrees Celsius by the end of the century, the Rhodium Group predicted in its latest forecast. The consultancy said its modeling showed a 67% likelihood that global temperatures will rise between 2.3 degrees and 3.4 degrees thanks to the current trajectory of planet-heating pollution. That’s a significant improvement on the dire predictions issued a decade ago. But if decarbonization doesn’t pick up pace, the probability of limiting warming to 2 degrees — the more modest target set in the Paris Agreement — is below 5%. Still, the findings don’t deviate much from Rhodium’s projections before Trump returned to office. As Heatmap’s Emily Pontecorvo wrote this morning, “in the long run, Trump might not mean much for the climate’s trajectory.”
Nevertheless, the overshoot beyond 2 degrees is partly why Bill Gates took a more moderate stance on climate change in his latest memo, as Heatmap’s Robinson Meyer wrote last week. It’s also why, as Rob explained in a big story, private companies promising to commercialize technology to geoengineer the world’s temperature are raising large sums of money.
The Department of Energy is stepping up its efforts to keep aging coal plants online. The agency on Friday announced plans to offer up to $100 million to owners of coal-fired power stations that plan to modernize the stations with upgrades that “improve efficiency, plant lifetimes, and performance of coal and natural gas use.” In a press release, Secretary of Energy Chris Wright praised President Donald Trump for having “ended the war on American coal” and “restoring common sense energy policies that put Americans first.”
Despite Trump’s promises to revive American coal production and use, exports fell 11% in the first half of this year due to China buying less of the fuel amid ongoing trade negotiations, according to an analysis published Friday by the Energy Information Administration.

In the latest sign that Wall Street is heeding Trump’s calls to veer away from investment initiatives that cut out fossil fuels, lending giant State Street’s asset management arm withdrew its U.S. operations from what was once a leading climate action group for the industry. The company said “it had decided that only its units serving UK and European clients would remain part of the Net Zero Asset Managers” group, the Financial Times reported. BlackRock, Vanguard, and JP Morgan Asset Management had already left the group known as NZAM in the U.S. JP Morgan and State Street had already also quit another green investor group, Climate Action 100+, last year.
Months after Taiwan shut down its final reactors earlier this year, a plurality of voters approved a referendum calling for the last atomic plant to be turned back on. Years after Germany completely exited nuclear power, the new government has reversed Berlin’s position and has now joined France in supporting atomic energy again as it considers ways to restore its fleet. Switzerland and Belgium, meanwhile, reversed plans to shut down nuclear plants, and Italy — the first country in the world to end its nuclear power production years ago — is working on reviving its industry. That leaves only Spain still stubbornly planning to close its nuclear plants starting in 2027.
The tides may be turning. In February, a majority of lawmakers in Spain’s parliament approved a resolution condemning Socialist Prime Minister Pedro Sanchez’s phaseout plans. Now the board of Spain’s Centrales Nucleares Almaraz-Trillo has officially requested a three-year extension on the operating license for units one and two of the Almaraz Nuclear Power Plant. If granted, the extension would allow the reactors to stay online through 2030. The station currently supplies 7% of Spain’s electricity.
Fusion energy, the joke goes, is the energy source of tomorrow — and always will be. But recent laboratory breakthroughs have unleashed billions of dollars in private financing to commercialize fusion energy for real, with companies promising to open power plants in the next decade. There’s a big bottleneck, however: Many of the materials needed for fusion reactors are scarcely produced right now. New bipartisan legislation aims to change that by extending the 45X tax credit for clean manufacturing — one of the few parts of the Inflation Reduction Act retained in Trump’s One Big Beautiful Bill Act — to producers of vanadium, deuterium, helium-3, and other materials needed for fusion power to take off.
It’s an off-off-cycle election year, but there are still a handful of key elections going on in Georgia, New Jersey, and Virginia.
With the Trump administration disassembling climate policy across the federal government, state elections are arguably more important to climate action than ever.
Here are the key races we’re watching where clean energy, public transit, and other climate-oriented policies are on the ballot.
There are only 10 states in the country that hold elections for a Public Service Commission, a small group of regulators who oversee utility companies, and Georgia is one of them. As Charles Hua, the executive director of the nonprofit PowerLines, recently put it, these officials are the “Supreme Court justices” of energy. They preside over what kinds of infrastructure gas and electric utilities will build, where they’ll build it, and how much rates will go up as a result.
The election in Georgia is long overdue after being held up by a lawsuit the last two election cycles. Two of the five current commissioners have served three extra years without being re-elected by voters. During that time, the commission has approved six rate increases for customers of Georgia Power, the largest utility in the state, in part to pay for major cost overruns on new nuclear reactors at Plant Vogtle. Now Georgia Power is proposing a major expansion of natural gas power — about 10 nuclear reactors’ worth — mostly to meet data center demand.
The two seats are held by Republicans Fitz Johnson and Tim Echols. They are being challenged by Democrats Peter Hubbard and Alicia Johson, who have vowed to push for Georgia Power to meet demand with clean energy.
Energy costs are at the center of the governors’ races in New Jersey and Virginia this year, and Democrats and Republicans are making opposite arguments about how to lower them. In New Jersey, Democrat Mikie Sherrill has vowed to freeze utility rates and clear red tape to “open the floodgates on new cheaper and cleaner energy projects,” including solar, battery storage, and nuclear. Her opponent, Jack Ciattarelli, thinks the key to lower prices is pulling out of the Regional Greenhouse Gas Initiative, a 13-state cap and trade program that incentivizes cleaner power generation and raises money for climate-friendly projects. He also wants to repeal the state’s electrification goals for vehicles and buildings and ban offshore wind development.
A similar fight is playing out in Virginia, although there it’s tied more to the state’s rapidly multiplying data centers. Virginia is already home to 13% of global data center capacity, with more coming online. A recent state legislative report warns that customers are looking at increases of $14 to $37 per month by 2040 as a result.
The Democratic candidate for governor, former U.S. Representative Abigail Spanberger, wants to expand solar and wind power and invest in building efficiency. She’s also advocated for data centers to “pay their fair share” of new energy infrastructure, and said she will encourage them to pilot advanced clean technologies like small modular nuclear reactors and hydrogen. She’s running against Winson Earle Sears, the current lieutenant governor of Virginia, who has questioned the reliability of renewable energy, arguing for an all-of-the-above strategy that includes “clean coal.” While “beautiful clean coal,” it may be one of Trump’s favorite energy sources, the reality is, it’s still just coal.
The governor’s seat isn’t the only one that’s up for grabs in Virginia. Whoever wins will need the House of Delegates on their side. Democrats currently have a razor thin 51-seat majority, and all 100 seats are on offer. Even a blue wave in the House doesn’t guarantee strong climate action, however, according to the nonprofit advocacy group Climate Cabinet. “Which candidates win will determine whether Virginia expands on” its climate law, the Clean Economy Act, “or backslides,” the group said in a “races to watch” memo.
Voters in Charlotte, North Carolina, and the whole of Mecklenburg County, will be asked whether to increase their sales tax by 1% to fund new transportation projects. Roughly 60% of the estimated $20 billion raised by the tax will go toward the expansion of rail and bus service. Charlotte is among the fastest-growing cities in the country. During a legislative hearing this summer, State Senator Mujtaba Mohammad said an average of 130 people move to the area each day. “We are experiencing longer commutes, more car accidents, higher car insurance premiums, more pedestrian-related accidents and less revenue to address our crumbling critical infrastructure," he said.
The Charlotte Area Transit System finalized a new long-range plan this year to foster “transit-oriented communities,” by increasing bus frequency, extending service hours, adding microtransit options to underserved neighborhoods, and adding 43 miles of new rail. But the plan is only possible with funding from the sales tax.
Sales tax increases are a common way to raise money for public transit systems — legislators in California recently voted to put a sales tax increase on next year’s ballot to address a looming fiscal cliff for transit in the Bay Area. Illinois also voted last week to increase the sales tax in the Chicago area by 0.025% to raise money for its ailing transit system, among other measures.
A few smaller elections where climate is also on the ballot this year, according to Climate Cabinet:
A new report from the Rhodium Group finds that the range of likely temperature outcomes has essentially not changed since 2023.
It’s that time of year when COP, the annual United Nations climate conference, draws near, and a flood of reports assess how much progress the world has made (or not made) to limit global warming. Given the sharp reversal in U.S. climate policy under President Trump, it may seem inevitable that the future will look bleaker than before. His administration has spent the past nine months dismantling nearly every bit of domestic climate policy implemented by its predecessor, and has even managed to thwart international efforts at climate cooperation.
The annual climate outlook from the Rhodium Group, a U.S. energy and climate research firm, offers a somewhat hopeful counterpoint to that narrative, however. It finds that the range of possible climate futures has essentially not changed in the past two years.
A full decade has passed since the landmark Paris Agreement on climate change, and in that time the world has avoided the most catastrophic scientific projections. In 2015, the UN’s Intergovernmental Panel on Climate Change, or IPCC, projected that global average temperatures could increase by as much as 7.8 degrees Celsius by the end of the century without significant shifts in policy and advancements in technology. Now, the Rhodium Group estimates that warming is highly unlikely to exceed 3.9 degrees by 2100, and could be limited to 2 degrees.
The numbers themselves are not hopeful. This is a vast range in terms of the potential impacts implied, and even 2 degrees of warming should not be considered “little.” The IPCC estimates that compared with a scenario that limits warming to 1.5 degrees, more than twice as many people would be exposed to severe heat at least once every five years in a world 2 degrees warmer; ice-free summers in the Arctic would occur 10 times more often; the number of plant, animal, and insect species that lose at least half their habitat would be two to three times larger; and crop yields and fisheries would suffer roughly twice the losses.
Putting those dire projections aside, what’s interesting is that this 2- to 3.9-degree range is about the same as what the Rhodium Group forecast when it published its first Climate Outlook report in 2023. Also relatively unchanged: a finding that global power sector emissions will peak within the next decade, and that total emissions will likely remain constant or subtly decline through 2060, but then go up again as Global South countries see more rapid economic development in the latter half of the century.
The reason the numbers haven’t changed much, despite some seemingly dramatic policy changes that have occurred in the interim, has to do with Rhodium’s unique approach to projecting the future.
Many of the reports that come out around this time, such as the UN’s annual Emissions Gap Report, try to assess where the world is headed based on currently enacted policies as well as pledges, such as the “nationally determined contributions” that countries submit to the UN. Those might include promises like, “We’ll build X quantity of renewable energy by 2030,” or “We’ll protect X amount of our forests.” The models assume that these policies and pledges are fixed. They do not contemplate future ramp-ups or potential reversals. They also use fixed assumptions about GDP and population growth, oil prices, technology costs, etc.
A recent report by Wood Mackenzie, for example, estimates that temperatures will climb to 2.6 degrees by 2060, and then models a few other potential discrete scenarios, including one that shows what it would take to limit warming to 2 degrees.
The limitation of this approach is that the trajectory for each variable these models use is deeply uncertain, Hannah Pitt, one of the authors of the Rhodium report, told me. “Even a small change in GDP growth can have really big implications for emissions — likewise for oil prices and renewable costs and all that,” she said. “We try to take into consideration the wide range of uncertainty we have in the future of those core drivers of emissions.” That requires modeling thousands of scenarios with different combinations of how those underlying drivers might evolve.
Then, rather than assuming that policies on the books today remain static, Rhodium uses data on how climate and energy policy has historically responded to economic inputs like oil prices and GDP growth, in different parts of the world to project how policy might change going forward, using a carbon price as a proxy for policy ambition.
This approach takes into account such a wide range of possibilities that the results aren’t likely to change much year to year. Both in 2023 and now, the modeling incorporated the prospect that a Trump administration or something like it could reverse some progress, and that energy demand could soar. “We are looking at the long-term evolution of policy, not the administration fluctuations,” Pitt explained. It would take a true step-change in policy or a major technological breakthrough to produce a noticeable change in the trajectory, she said.
What are those breakthroughs? At this point, they aren’t a mystery. Cheaper clean firm power — like advanced nuclear, fusion, or geothermal — would be a huge help. Solutions for decarbonizing flying and shipping are also on the list. We also need to make it affordable to produce iron, steel, cement, and petrochemicals with far fewer emissions.
On the policy side, bending the curve might mean something like stricter electric vehicle requirements. As mentioned earlier, economic development in the Global South is expected to shift emissions back upward later this century — in part because if policy evolves the way it has historically, and if more and more people around the world are buying cars, the cars may not be 100% electric, and emissions from transport will go up.
None of this is to say that the Trump administration’s actions will have no effect on warming. Recall the report’s expansive range of future warming scenarios of 2 to 3.9 degrees — it’s very possible that policies enacted today will push the world closer to one or the other. A separate recent Rhodium study that dives into the specifics of U.S. policies found that emissions in 2035 could be 0.8 to 1.2 gigatonnes higher than what the group projected in the same report last year, largely due to Trump’s policies.
It should be comforting that one administration can’t veer the world too far off course — although by that same logic, we can’t expect a single administration to shift projections in a positive direction, either. A "breakthrough" in something like decarbonized cement will likely happen over years, through a feedback loop of sustained policy support and technological development.
There is no “too late” when it comes to addressing the technology and policy gaps the report highlights, Pitt said “Of course, the sooner the better,” she said. “But the difference between a 2.8-degree future and a 2.5-degree future saves lives. So the effort to drive these technology costs down is worthwhile, even if it doesn’t happen on the timeline that we would hope.”