A new study highlights how the United States can make significant strides toward reducing greenhouse gas (GHG) emissions by 2035, aiming directly at enhancing its climate commitments under the Paris Agreement. This multi-model research, involving four U.S. energy modeling teams, evaluates the potential impacts of expanded federal and state policies beyond the current measures.
The urgency of this study arises as countries prepare to submit updated nationally determined contributions (NDCs) by 2025, reflecting their plans for emission reductions. The findings suggest the U.S. could achieve between 56-67% reduction of emissions relative to 2005 levels by implementing these ambitious policy measures. This is markedly higher than the current measures, which are projected to lead to only 34-44% reduction.
According to the authors, "An ambitious and plausible 2035 NDC in the United States could be pivotal for motivating global climate action." This statement underlines the significant role the U.S. plays as the world's largest economy and second largest emitter of GHGs, highlighting the need for it to lead by example.
The study examined multiple scenarios, analyzing the economic and energy system impacts resulting from various policy approaches. Key findings reveal not just the expected reduction percentages but also substantial changes needed across several sectors, including electricity generation, transportation, and buildings.
One of the standout insights indicates the electricity sector could reach near-zero emissions under the highest ambition scenarios due to the implementation of stringent clean energy standards and widespread adoption of electric vehicles (EVs). Specifically, the research projects EVs will account for 83-100% of light-duty vehicle sales by 2035 under these conditions.
"Our study provides a framework for decision-makers to inform ambitious and plausible pledges," the authors add, emphasizing the importance of collaborative, science-based approaches to inform future climate policy.
The methodology involved utilizing several models to provide bottom-up estimations of sectoral emissions reductions and energy impacts through 2035. The scenarios included current measures as well as proposed actions like stricter regulations on fossil fuel power plants, enhanced renewable portfolio standards, and significant electrification of heating and vehicle fleets.
The potential transformations highlighted by the study point to increased renewable energy capacity additions, which would need to rise by two to four times compared to historical levels to meet ambitious targets. The current modeling suggests the U.S. would need to add between 62-102 GW per year of renewable energy, driven largely by policy enhancements and technological advancements.
Sector-specific analyses revealed the considerable contributions of the power, transportation, and buildings sectors to overall emissions reductions. For example, the power sector could see reductions ranging from 60-76% relative to 2005 levels, with the transportation sector contributing significantly more under higher ambition measures.
Despite the optimistic projections, the study acknowledges gaps between current policies and the necessary actions required to close the emissions reductions needed by 2035 to remain compliant with net-zero trajectories projected for 2050.
The findings stress urgent action is needed not just from federal policies but also through state and local government collaboration, alongside private sector initiatives. This collective effort is deemed necessary to meet and potentially exceed the benchmarks set forth under the U.S. long-term strategy for achieving net-zero emissions.
Some of the notable barriers highlighted include the potential revocation of existing policies, slow deployment of necessary technologies, and broader market challenges. The authors caution about the feasibility of sustained political and social commitment to these ambitious targets.
Importantly, the research calls for additional supporting measures to be considered, such as incentivizing investments and consumer acceptance strategies. Addressing these challenges is fundamental for ensuring the U.S. can fulfill its commitments and influence global climate initiatives positively.
Through this multi-model approach, the study not only offers insights specific to the U.S. but also provides valuable frameworks applicable to countries worldwide as they approach their own NDC updates. The collaborative findings signal the importance of timely action and sustained engagement across political, economic, and social landscapes to achieve meaningful climate progress.