NRDC Analysis: Nuclear Energy and a Safer Climate Future

This is part of a series of blogs on NRDC’s new report, “America’s Clean Energy Frontier: The Pathway to a Safer Climate Future”

NRDC’s report America’s Clean Energy Frontier: The Pathway to A Safer Climate Future lays out a clean energy pathway for cutting U.S. greenhouse gas pollution 80 percent from 1990 levels by 2050. These emissions cuts are necessary to avoid the most devastating impacts of climate change. Our analysis shows that the U.S. can reach its 2050 carbon goals even with a steep decline in U.S. nuclear power as American reactors age and the economics of new nuclear reactors remain extremely challenging.

NRDC’s plan relies on existing technologies to cost-effectively achieve a clean, low-carbon future. Energy use is cut by 50 percent through efficiency and electric investments, with our cars achieving an average of 100 mpg. Wind and solar energy grow 13-fold from today’s levels, with renewables providing at least 80 percent of our power, allowing us to electrify buildings and cars to run with renewable energy. And a stronger, smarter and more resilient electricity grid supports the integration of these clean energy resources. By 2050, nuclear power provides just 3% of U.S. electricity, down from about 20% today, as aging U.S. nuclear power plants reach the end of their operating licenses.

Modeling a Potential for U.S. Nuclear Decline

The reduced role of nuclear power in NRDC’s pathway model primarily stems from the economic challenges facing the nuclear industry and the aging of the existing U.S. nuclear fleet. Our core scenario has only 20 gigawatts (GW) of nuclear power plant capacity operating in 2050: an 80 percent decline from today. Due to the high cost of constructing new nuclear power plants and the current wave of nuclear retirements before the expiration of their Nuclear Regulatory Commission (NRC)-issued licenses, NRDC’s modeling assumed that only four nuclear reactors would be built between now and 2050 (and that may be optimistic).


The United State has 99 operating nuclear power reactors, but early retirement plans have been announced for seven reactors because of economic pressures. In addition, most U.S. nuclear power plants were built in the 1960s, 70s, and 80s. These reactors have 60-year extended operating licenses, most of which will have ended by 2050—the target date for reaching an 80 percent reduction in greenhouse gas emissions. Some may be able to get and to use an additional 20-year extension—but we assumed that only about one in five existing plants would operate beyond 60 years due to economic and safety challenges. Our plan shows increased renewable energy deployment more than makes up for the lost low-carbon benefit of nuclear generation. We are also skeptical of the role of what is called “advanced nuclear” for generating the electricity to run our homes and businesses in the time frame to mid-century—acknowledging that other researchers have projected a significant contribution from advanced nuclear in their modeling of 80% carbon reduction by 2050. We believe that a crucial challenge for advanced nuclear is that no working prototypes of such reactor designs exist or are firmly planned, and thus deployment at scale is generally uncertain but highly unlikely in the first half of this century.

This isn’t ideological hostility to nuclear power; it is pragmatic skepticism. NRDC is not opposed in principle to nuclear power, and acknowledges its beneficial low-carbon attributes in a warming world. However, we take seriously the significant safety, global security, environmental, and economic risks that use of this technology imposes on society. They include: environmental harms from uranium mining; safety and security of nuclear plant operations; nuclear weapons proliferation impacts; and spent fuel disposal. This demands more stringent, improved policy and regulation of the complete nuclear fuel cycle, beginning with the mining and milling of uranium and ending with the final disposal of radioactive wastes. Until these risks are properly mitigated, expanding nuclear power should not be a leading strategy for diversifying America’s energy portfolio and reducing carbon pollution.

Reinforcing this perspective, nuclear power is uneconomical compared to alternate forms of low-carbon electricity generation—even without considering those risks. Faced today with the seemingly irreversible decline of nuclear energy in the United States, and the enormous potential to scale up energy efficiency and renewable energy on a stronger electric grid, NRDC’s analysis concludes we can meet our U.S. climate goals even with a much-reduced nuclear fleet.

NRDC Recommendations on Nuclear Energy

Our report puts forward three nuclear-related recommendations that logically follow from NRDC’s climate and energy policy analysis and projections:

Regulators should explore approaches for replacing retiring nuclear units with zero-carbon resources and protecting the livelihoods of workers and host communities. As U.S. nuclear plants reach the end of their operating licenses or becomes uneconomical to run, growing numbers of reactors are likely to be retired. Regulators and other stakeholders will need to avoid abrupt closures, which could result in carbon emission increases from replacement generation. They should instead plan for shutdowns with sufficient time to ensure the lost power is reliably replaced with clean energy, and the livelihoods of workers and nearby communities are protected. The Joint Proposal to replace California’s only remaining nuclear power plant, the two Diablo Canyon reactors in San Luis Obispo, provides a model of an appropriate transition plan.

The Environmental Protection Agency (EPA), NRC, and states should address existing nuclear safety and fuel issues. The EPA and NRC should adopt stronger regulations to address the environmental impacts of uranium mining as well as the safety and security risks associated with nuclear plant operations. The federal regulations governing the decommissioning of nuclear power reactors need to be fundamentally overhauled. Rather than relitigate unworkable ideas like the Yucca Mountain site in Nevada, the federal government should develop a scientifically defensible and publicly accepted consent-based siting process for geologic disposal of spent nuclear fuel. Accordingly, Congress should amend the Atomic Energy Act of 1954 to remove its express exemptions of radioactive material from environmental laws, thus creating a regulatory role for the EPA and the states in nuclear waste disposal.

The federal government should continue to fund research into nuclear energy. Long-term federal investment in energy technologies is a key aspect of federal energy policy, including DOE programs that support R&D for nuclear fuel cycle and reactor designs. Government spending on advanced nuclear R&D must prioritize the analysis of severe accident scenarios and security vulnerabilities. While cost estimates for advanced nuclear designs should be rigorously examined early in their R&D cycle, the cost and reliability assessments can only be realistically understood based on the performance of an advanced nuclear prototype and a first-of-a-kind commercial reactor. Highly expensive projects should be evaluated as public-private partnerships to judge market viability for a given advanced nuclear design. Nuclear weapons proliferation impacts should also be addressed early in the R&D cycle; advanced nuclear designs that require a closed nuclear fuel cycle to reprocess spent nuclear fuel should be rejected outright given the associated proliferation risk, high cost and production of secondary nuclear wastes.


NRDC’s analysis and recommendations focus on the time period from today to 2050. Between now and 2050, it is likely that the majority of today’s nuclear power plants will retire based on economics and license expiration alone. NRDC’s modeling and analysis shows that, if such is the case, we can replace nuclear generation with clean, renewable energy instead. Nevertheless, deep geologic storage of spent fuel and nuclear weapons proliferation will remain important problems for the United States along a pathway to a safer climate future in 2050. Whether new forms of nuclear power emerge and play a role after 2050 remains to be seen.

About the Authors

Matthew McKinzie

Senior Scientist, Land & Wildlife program, and Director, Nuclear program

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