Low-Carbon Portfolio Standards


May 18, 2016 | Ted Nordhaus, Jessica Lovering, Michael Shellenberger, Will Boisvert, Jack Shaked,

Expanding existing state Renewable Portfolio Standards (RPS) into Low-Carbon Portfolio Standards (LCPS) would more than double the statutory requirements for clean energy in the United States. Such a policy shift would prevent the premature closing of many of America’s nuclear power plants and assure that nuclear power plants will be replaced with low-carbon electrical generation when they are retired.

Read the full report here.

In aggregate, the existing RPSs require a total of 420 terawatt-hours of annual renewable generation across 30 states and Washington, DC by 2030. If nuclear were included in new low-carbon standards in all states that currently have both RPS policies and operating nuclear plants, the mandated amount of clean energy would increase to 940 terawatt-hours of annual carbon-free electricity. Assuring these additional 520 terrawatt-hours of electricity remain low-carbon would prevent 320 million metric tons or carbon dioxide emissions, or 17% lower than would otherwise be the case. 

Replacing carbon-based sources of energy with low-carbon sources remains the most reliable indicator of long-term progress toward emissions reduction goals. In the power sector, Renewables Portfolio Standards have been a driving force behind deployment of renewable energy technologies in the United States. However, nuclear generation in the United States has stagnated over the last 20 years and may decline substantially in the coming decades. If existing nuclear plants close prematurely and are replaced with natural gas, as is likely, much of the gain in low-carbon share of US electricity generation associated with renewables deployment will be lost.

The loss of clean and reliable nuclear power will make the challenge of decarbonizing the US power sector much more difficult. This loss of clean electricity will threaten US climate commitments made as part of the Paris Agreement under the United Nations Framework Convention on Climate Change in December of 2015. This is true even if wind and solar replace a substantial share of the lost generation from retiring nuclear plants, since every megawatt-hour of nuclear replaced by renewables is a megawatt-hour renewables can’t replace from fossil fuels. As such, transforming RPSs into LCPSs would move the ball sig- nificantly farther downfield towards full power-sector decarbonization by midcentury.

In this report, we recommend expanding state Renewable Portfolio Standards into more ambitious Low-Carbon Portfolio Standards to include existing nuclear power plants. An LCPS would assure that premature retirements of existing nuclear plants do not erode some or all of the carbon and clean energy benefits of continuing deployment of wind and solar power in the short-term, while significantly raising the statutory requirement for deployment of low-carbon electricity generation over the long-term. LCPSs would also include new nuclear power, hydroelectric power, and fossil fuels with carbon capture and storage. 



Jesse Jenkins, "Which Nations Have Reduced Carbon Intensity Fastest?" April 3, 2012

Roger Pielke, Jr, "Clean Energy Stagnation," July 9, 2013

Max Luke, "Nuclear and Gas Account for Most Carbon Displacement Since 1950," September 3, 2013



"Frequently Asked Questions About Nuclear Power"

"Moderate Environmentalists Go Nuclear"

"Top Climate Scientists Urge Support of Nuclear Power"


Jessica Lovering, Ted Nordhaus, and Michael Shellenberger, "Out of the Nuclear Closet," September 2012



Editorial Board, "Don't Give Up on Nuclear Energy Yet," September 5, 2013

Eduardo Porter, "Coming Full Circle in Energy to Nuclear," August 20, 2013

Bryan Walsh, "New Nuclear Reactor Designs Could Address Safety and Cost Concerns," August 5, 2013

Amy Harder, "Can the US Government Revive Nuclear Power?" November 23, 2014

Tim McDonnell, "Obama's Deal with China Is a Big Win for Solar, Nuclear, and Clean Coal," November 12, 2014

Ashutosh Jogalekar, "Making Nuclear Energy Cheap," June 20, 2014

Martin LaMonica, "U-Power's Truck-Size Nuclear Power Plant," May 15, 2014

Robert Bryce, "A Nuclear Option for Energy," May 9, 2014

Ben Geman, "Greens Still See Red On Nuclear," February 2, 2014

Michael Shellenberger and Ted Nordhaus, "Can Climate Skeptics Save the Planet?" September 27, 2013

Ashutosh Jogalekar, "Nuclear vs. Renewables: A Tale of Disparaties," August 22, 2013

Bob Dreyfuss, "The IPCC Report and Nuclear Energy," August 21, 2013

Eduardo Porter, "Coming Full Circle in Energy, to Nuclear," August 20, 2013

Mark Halper, "Newfangled reactors will slash costs of nuclear power," July 16, 2013

Eliza Strickland, "Can Nuclear Reactors Be Cheap?" July 12, 2013

Fred Pearce, "New Green Vision: Technology As Our Planet's Last Best Hope," July 15, 2013

Bryan Walsh, "Nuclear Energy is Largely Safe. But Can It Be Cheap?" July 8, 2013

Michael Shellenberger and Ted Nordhaus, "Going Green? Then Go Nuclear," May 22, 2013

Joe Garofoli, "Some Environmentalists Back Nuclear Power," June 13, 2013

Robert Bryce, "Rise of the Nuclear Greens," March 7, 2013

Colbert Report, "Tonight's guest: Michael Shellenberger explores global energy consumption, nuclear power and lessons from Frankenstein," January 28, 2013

Tim Wu, "If You Care About the Environment You Should Support Nuclear Power," January 24, 2013