Click on a candidate to jump to their section: Joe Biden | Pete Buttigieg | Kamala Harris | Bernie Sanders | Elizabeth Warren | Michael Bennet | Cory Booker | Julián Castro | John Delaney | Tulsi Gabbard | Amy Klobuchar | Tom Steyer | Marianne WilliamsonAndrew Yang

It can be difficult to keep track of who's who in the scrum of Democratic presidential candidates, let alone where their policy differences lie. GTM is here to help.

We’ve parsed where each candidate in the Democratic presidential primary stands on energy and environmental issues, how their climate plans stack up and what their track record says about them.

Climate change scarcely got a mention during the 2016 election. But the political conversation has shifted over past months, due in part to the intrigue, activism and controversy surrounding the Green New Deal. In September, pressure from activists even compelled CNN to hold a seven-hour town hall completely dedicated to the topic. 

Democrats have also been galvanized by President Donald Trump, whose administration has proposed deep budget cuts to clean energy innovation programs like ARPA-E, promised to pull out of the Paris climate agreement and, according to the New York Times, begun or executed 83 rollbacks of environmental rules.

There's substantial overlap among the Democratic candidates on energy and climate issues. Nearly everyone endorses a return to the Paris agreement. Support for the Green New Deal is a given among the top-tier runners.

Yet there are important differences, too, in substance and in style. The future of nuclear energy is one emerging fault line, as is the speed and scope at which fossil fuels should be phased out.

There are also differences in how much attention the candidates are paying to these issues. Washington Governor Jay Inslee, who dropped out of the race in August, anchored his entire campaign to the topic. Some, like Massachusetts Senator Elizabeth Warren, call for top-down, government intervention and clean energy funding. Others have preferred to leave more power to the private sector.

Editor's note: The story was last updated September 10, and will continue to be updated as primary season rolls on.

The Top Tier

Joe Biden

The former vice president and current frontrunner in the polls was the first to introduce climate legislation in the Senate in 1986. Since joining the presidential race, though, he’s gotten middling reviews from the environmental community. Biden's initial climate plan earned the candidate a 'D-' grade from Greenpeace, but that was later upped to a 'B' as he issued more details.

Biden’s campaign calls his climate platform a “clean energy revolution.” It requires $1.7 trillion in direct federal investment over a decade and calls for 100 percent clean energy, net-zero emissions by no later than 2050 alongside the creation of an Advanced Research Projects Agency for climate. Biden says he would sign a series of executive orders while demanding Congress pass legislation mandating historic levels of investment in clean energy.

The legacy Biden built alongside President Obama includes $90 billion for clean energy programs as part of the American Recovery and Reinvestment Act of 2009. His reputation as a political moderate could give him more leeway to cut deals with Republicans once in office, at least in theory.

Though parts of Biden’s plan have earned plaudits from environmental groups, the original document faced controversy due to apparent plagiarism. The campaign said it had inadvertently left out some citations. Though the updated plan goes further than the “middle ground” approach Biden aides told Reuters he’d take, environmentalists are already pushing the party’s front-runner for further details and more drastic action — including a pledge to phase out fossil fuels, which Biden has avoided.

Biden faced further scrutiny in September, when he attended a fundraiser hosted by the co-founder of a natural gas company. Though activists urged Biden to reconsider attending, his campaign said the event did not violate the No Fossil Fuel Money Pledge the former vice president signed. 

Pete Buttigieg

The South Bend, Indiana mayor favors the implementation of a Green New Deal “with all available tools,” such as a carbon tax-and-dividend scheme and investment in 100 percent clean energy.

Buttigieg oriented his climate plan around three pillars: a clean energy economy, resilience and U.S. leadership. It calls for 100 percent clean electricity by 2035 and a carbon-neutral economy by 2045 at the latest. His plan would set aside $250 billion for a Global Investment Initiative, with an equal match from the private sector, to export U.S.-incubated technologies abroad. It also includes a CarbonStar program, modeled after EnergyStar, which would offer residents information about a product's carbon footprint. A Buttigieg administration would also create Regional Resilience Hubs, advised by a board of elected leaders and community members, to identify and implement local resilience solutions. 

Buttigieg also favors carbon capture and said tax credits supporting the technology "should be extended and broadened."

Though many of these ideas would require action in Congress, Buttigieg's campaign said he would employ "every executive authority available" to achieve the goals laid out in the plan.

In the past the mayor has boosted the potential of net-zero building retrofits in reducing energy use, suggesting that “Uncle Sam is gonna mail [people] a kit” to add solar to their roof.

He signed the pledge rejecting money from fossil fuel donors, and as mayor joined the Mayors National Climate Action Agenda, a group of mayors that committed to the goals of the Paris pact.

Kamala Harris

“From wildfires in the west to hurricanes in the east, to floods and droughts in the heartland, we’re not gonna buy the lie," said California Senator Kamala Harris, highlighting climate change in her campaign’s launch speech.

"We’re gonna act based on [scientific] fact, not science fiction,” she said in Oakland.

Harris, along with Representative Alexandria Ocasio-Cortez, unveiled the Climate Equity Act in July, which aims to center frontline communities in federal climate policy. As president, Harris said she'd work to pass that legislation. Meanwhile, she would reinstate and expand a Clinton-era executive order that requires federal agencies to consider environmental justice in decisionmaking.

Harris threaded environmental justice themes throughout her climate plan as well, with plans to model other programs after initiatives like California's Community Air Protection program and pass the 21st Century SKILLS Act, legislation she introduced that would offer up to $8,000 for unemployed, dislocated or underemployed workers for skills training and education. 

The Senator is a cosponsor of the Green New Deal and has signed a pledge promising to reject money from the oil and gas industry. In a recent CNN town hall centered on climate change, Harris said she would ban fracking on public lands and work with Congress to abolish it everywhere (at the same event, Harris said she'd work with lawmakers to get rid of the filibuster, which could ease passage for environment and climate-related legislation). 

Environmentalists are generally happy with her past record. In 2016, Harris tweeted that she supports a national standard requiring 40 percent renewables for electricity by 2035. 

While working as San Francisco’s District Attorney, she created an environmental justice unit to tackle environmental crimes impacting low-income residents. And after rising to state attorney general, Harris joined other state AGs in investigating ExxonMobil’s knowledge of climate change. She also navigated a settlement with Chevron tied to pollution.

Bernie Sanders

In August, Sanders released a climate plan heralding "the decade of the Green New Deal" that he would kickstart as president. The plan directs $16.3 trillion to policies such as reaching 100 percent renewable electricity and transportation by no later than 2030, creating 20 million union jobs and apportioning $40 billion to a Climate Justice Resiliency Fund for frontline communities.

Like the GND legislation introduced in the Senate — which Sanders co-sponsored — the Senator's plan frames climate change as a labor and justice issue. It promises to increase environmental regulations and remake the energy sector, while also proposing big changes to transportation, infrastructure and the economy. Under Sanders, electricity would be produced and sold through publicly-owned entities. 

Sanders's campaign said the big investment tied to his plan will be repaid in 15 years, in part through the elimination of fossil fuel subsidies and increased taxes on large corporations. 

In the past, Sanders has advocated for investment in clean transportation, banning fossil fuel extraction and ending the export of fossil fuels.

But he’s not excited about all forms of carbon-free energy: Sanders has called for a halt to new nuclear plants and license renewals for existing ones, citing concerns about nuclear waste and the cost of federal subsidies for the industry.

Elizabeth Warren

Massachusetts Senator Elizabeth Warren, another co-sponsor of the GND resolution, has released multiple plans to tackle greenhouse gas emissions at home and abroad while revitalizing the U.S. economy in the process. After Inslee dropped from the race, Warren borrowed from what he called "open source" climate plans to expand her own policies. 

The most recent plan from Warren — whose "I've got a plan for that" catchphrase has made its way onto campaign t-shirts — aims to center environmental justice in federal decisionmaking. Warren said she would implement an "equity screen" for climate-related investments and direct one-third of the funds associated with her previous plans, a sum she quantifies as at least $1 trillion, to vulnerable communities on the frontlines of climate change, among other proposals. 

Warren has also promised to retire coal in a decade, build to 100 percent zero-emission renewable electricity by 2035 and reach zero-emission transportation and buildings by 2030. 

Her past plans offer some details on how a Warren administration would reach those mandates: outlining $400 billion in federal R&D spending on clean energy over the next decade, framed as a Green Apollo Program in reference to the moon landing mission. Her administration would also require manufacturing that results from government-funded research to take place in the U.S., to maximize benefits to the national economy. Warren also called for $1.5 trillion in federal procurement commitments for clean energy over the next decade, and a Green Marshall Plan to spread American cleantech products overseas.

Another earlier plan would turn the Pentagon into an engine of clean energy deployment, taking non-combat operations and infrastructure carbon neutral by 2030, and helping the military harden itself against climate-related threats.

Warren would also freeze new leases for fossil fuel extraction on public lands and instead require 10 percent of the nation’s electricity to come from renewable plants offshore or on public lands. She supports ending fracking on public and private lands. During a CNN town hall on climate, Warren said she opposes new nuclear and would look to phase out already-operating nuclear plants. 

Everybody Else

Michael Bennet

Colorado Senator Michael Bennet touts a long history of prioritizing climate resilience and clean energy. He made climate the focus of his first major policy proposal as a presidential candidate, which calls for net-zero emissions by 2050 at the latest.

More unusual ideas in the plan include: Requiring power providers to offer customers a clean power option; a “Race to the Top”-style contest for states to earn federal infrastructure investment by taking action on carbon emissions; conserving 30 percent of the nation’s lands and ocean territory; funding a $1 trillion Climate Bank to inspire 10 times as much private follow-on investment; and using his first 100 days in the White House to “engage people from across the country” to crowd-source a national climate strategy.

Cory Booker

Booker, a Senator from New Jersey, has touted an environmental justice plan on the campaign trail. He’s promised to increase staff in the Environmental Protection Agency’s office of environmental justice by ten times and double enforcement staff. He’s also a member of the newly formed environmental justice caucus in the Senate.

Environmental justice also featured prominently in the $3 trillion climate plan Booker released in September. He wants to create a U.S. Environmental Justice Fund, which would get $50 billion annually to cope with issues like lead pipe replacement and Superfund remediation where the responsible party is bankrupt or can't be identified. Booker would also set up an Environmental Justice Innovation Fund to research and scale environmental justice solutions and an Emergency Environmental Justice Action Program, which would work to cut through bureaurcracy during emergencies like the Flint Water crisis. Like his peers, Booker has also included plans for a service program — his version, the Civilian Conservation Corps, borrows its name directly from a New Deal-era program —  that would offer training and work to 150,000 young people in environmental justice communities.

The Senator has shown consistent support for nuclear as a solution and his plan includes $20 billion for the development of next-generation advanced nuclear. Booker also sets aside $400 billion for clean energy R&D, with "Moonshot Hubs" located in all 50 states to scale technologies. Booker is among the candidates that support a carbon fee and dividend, which would vbe distributed to U.S. households. 

He’s also a sponsor of the Green New Deal and has worked to extend tax credits for wind and solar in the Senate. He has signed a pledge rejecting campaign contributions from the fossil fuel industry.

Julián Castro

The $10 trillion (public and private funding) climate plan that the Former Housing and Urban Development Secretary dropped in September would achieve net-zero emissions by 2045. It includes $200 billion for a Green Infrastructure Fund that the Castro campaign said would leverage $600 billion in state, local and private investment to fund clean energy technologies like charging infrastructure and smart grid improvements. 

Castro has also made environmental justice central to his plans. In June he unveiled a plan to cope with lead contamination, which has impacted communities like Flint, Michigan, by designating $50 billion over ten years on remediation. His more recent climate proposal lays out plans to include carbon equity scoring on federal spending and convert to law a Clinton-era executive order that requires federal agencies to consider environmental justice.

The former San Antonio mayor also has clean energy bona fides from boosting renewables in local government. In 2011, he declared “San Antonio has the opportunity to seize a mantle that no city in the U.S. holds today: To be the recognized leader in clean energy technology,” while unveiling a six-year development package that included a 30-megawatt solar farm from SunEdison and incentives to bring clean energy companies to the city.

At the time, the city’s utility was working to reach 20 percent clean energy by 2020 (the utility looked to have reached 19 percent in 2018, though it’s recently faced blowback over the speed of its transition).

Castro’s brought a similar message to campaigning; he recently told the New Yorker, “in my neck of the woods of Texas ... there is a new energy economy out there that is at the nexus of both reducing carbon emissions and protecting the planet, and also creating good jobs for people as the economy changes.”

At the same time as greening San Antonio, though, Castro has celebrated the economic benefits the shale boom has brought to Texas. At a September CNN town hall that focused on the climate crisis Castro grappled with that past support. “We believed natural gas was a bridge fuel. We’re coming to the end of the bridge,” he said. Though Castro would end drilling and fracking on public lands, he stopped short of the commitments of some peers that would outlaw extraction on all U.S. lands. 

Castro endorsed the Green New Deal and has also said returning the U.S. to the Paris agreement would be his "first executive action" as president. 

John Delaney

The former congressman from Maryland dropped his climate plan in May. The $4 trillion platform proposes increasing funding for Department of Energy clean energy programs, such as the Office of Energy Efficiency and Renewable Energy and the Advanced Research Projects Agency-Energy, by a factor of five.

Delaney also proposes “challenge grants” to drive innovation in several key areas, including freight electrification and energy storage and transmission.  

Delaney also supports a “carbon fee and dividend” at $15 per ton, increasing by $10 per year. He doesn’t support the Green New Deal, however, and hasn’t signed a pledge to reject money from the fossil fuel industry.

Tulsi Gabbard

Tulsi Gabbard, a U.S. Representative from Hawaii, co-sponsored a 2015 resolution declaring that the House favors a move to 100 percent clean energy, and in 2017 she introduced a bill requiring 100 percent clean energy by 2035 (spoiler: neither passed). In a questionnaire submitted to the New York Times, Gabbard mentions grid modernization and energy storage as areas deserving research funds.

She is not a co-sponsor of the Green New Deal. Gabbard told the Washington Post she supports the carbon neutrality goals of the resolution, but she doesn’t want nuclear as an option. The lawmaker supports a phase-out of fossil fuels.

Amy Klobuchar

Minnesota Senator Amy Klobuchar is another sponsor of the Green New Deal, but her climate plan is relatively moderate compared to those of many other candidates. 

Klobuchar calls for net-zero emissions by mid-century, which she'd accomplish in part through an unspecificied carbon price and clean energy bonds. Her administration would work to extend tax credits for renewables and would also institute credits for grid improvements, energy storage and electric vehicles. There'd also be a tax credit for companies who hire former fossil fuel workers.  

As president, Klobuchar has said she would “put forward sweeping legislation that provides a landmark investment in clean-energy jobs and infrastructure, provides incentives for tougher building codes, promotes rural renewable energy and development, and promotes ‘buy clean’ policies.” That legislation, of course, would be subject to cooperation and approval from Congress. But the lawmaker has also said she'd focus on executive actions, like tightening vehicle fuel economy standards and expanding the Clean Power Plan, to push climate action. 

She has signed a pledge to reject any campaign contributions from the fossil fuel industry. Klobuchar has also promised to recommit the U.S. to the Paris climate agreement on her first day in office (and strengthen U.S. commitments, per the Washington Post). 

Like many candidates, she also favors doing away with subsidies for fossil fuels. Klobuchar co-sponsored a 2017 bill that would have limited or ended those tax credits. According to the New York Times, Klobuchar takes a favorable view towards new nuclear development.  

 Tom Steyer

California billionaire Tom Steyer is no stranger to climate advocacy. He founded the organization NextGen America to mobilize voters specifically around the issue. Climate change is still central to its mission, though the organization now also focuses on issues such as immigration and healthcare.

After joining the 2020 race in July, Steyer unveiled a five-part climate plan that his campaign said would focus on justice. The plan includes a target of 100 percent clean energy and net-zero pollution by “no later than 2045.” On the first day of his presidency, Steyer also said he will “declare the climate crisis a national emergency.” Over a decade, Steyer proposes a $2 trillion federal investment in infrastructure, with a portion of that money going to updating the electricity grid. Like several of his peers, Steyer also proposed a clean jobs program that his campaign calls a “civilian climate corps.” He supports the idea of a Green New Deal.

In September, Steyer dropped an additional, international climate plan that promises to recommit to the Paris agreement, strengthen U.S. goals and engage in international collaboration on efforts like accountability on environmental crimes. It also earmarks $200 billion over 10 years for the UN’s Green Climate Fund and a Global Green New Deal Fund, a U.S. led initiative focused on leveraging global private capital for climate projects.

Marianne Williamson

Marianne Williamson, a motivational speaker and bestselling author of New Age self-help books, supports increasing investments in clean energy, extending tax credits for renewables and transitioning away from fossil fuels and nuclear energy, though her website does not offer specific policies on how those goals would be accomplished. She proposes a price on carbon to help meet climate targets.

Williamson supports the Green New Deal, though she claims on her campaign website that it “doesn’t cover the whole range of measures we must undertake to reverse global warming.” She would also rejoin the Paris agreement and reinstitute the Clean Power Plan, which the Trump administration replaced with the Affordable Clean Energy rule.

Andrew Yang

Many of entrepreneur Andrew Yang's climate-related policy proposals are unusual compared with the rest of the democratic field. He's boosted the need for geoengineering; though Yang said those technologies wouldn't be his "primary approach" to combatting climate change, his climate plan also calls for investments in technologies such as "space mirrors," which would reflect the sun's rays away from earth. 

Employing $4.87 trillion over two decades, Yang would create a Department of Technology, build out new national labs and build a "fully-green economy" by 2049. In addition to fighting warming, Yang wants to "move our people to higher ground" using $40 billion in "subsidies, grants and low-interest loans" to relocate U.S. residents from regions that will be impacted by natural disasters and rising seas.

Those proposals build off of Yang's other ideas, including such dark horses as “Empowering [mixed martial arts] Fighters” and “NCAA Should Pay Athletes.” 

These sorts of techno-optimistic planks set Yang’s platform apart from his competition, but he also favors more humdrum proposals like expanding nuclear energy and investing $200 billion in grid modernization. 

Want more? You can also listen to our Energy Gang episode examining the climate plans of 2020 candidates.

(Story reported and written by Emma Foehringer Merchant and Julian Spector.)