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President Joe Biden took the stage at the high-stakes COP26 climate summit in Glasgow, Scotland, on Nov. 1 seeking to assure the world that the U.S. is tackling greenhouse gas emissions head-on even as his policies have been scaled back by Congress and could be blocked by the U.S. Supreme Court.

In lieu of the political wins Biden had hoped to bring to the global climate conference, the White House released a long-term climate strategy reaffirming the emission reduction goals the president unveiled earlier this year. The report describes how the U.S. plans to cut carbon emissions in half by 2030, rid the energy sector of fossil fuels by 2035 and reach net-zero emissions by 2050.

"We're going to cut U.S. greenhouse gas emissions by well over a gigaton by 2030," Biden told thousands in attendance at COP26. "We're planning for both a short-term sprint to 2030 that will keep 1.5 degrees Celsius in reach and for a marathon that will take us to the finish line and transition the largest economy in the world into a thriving, innovative, equitable and just clean-energy engine."

The strategy document notes that "rapid decarbonization" is underway in the electricity sector as the U.S. attempts to adhere to the 2015 Paris Agreement on climate change, in which nations agreed to try to limit global temperatures from rising past 1.5 degrees C from preindustrial levels. With sheer market changes such as continued cost declines for renewable energy and battery storage technology, emissions could decrease 70% to 90% by 2030 and reach 100% five years later, the U.S. plan suggests.

That will require a massive build-out of energy storage over the next 30 years. The Biden strategy calls for up to 2.7 GW annually by 2030, up to 40 GW per year in the ensuing decade and as much as 64 GW in the 2040s. By comparison, about 10 GW are in the development pipeline between now and 2030, according to a recent report by the U.S. Energy Information Administration.

The Biden administration's 2035 decarbonization target for the power industry has not yet been adopted by U.S. utilities, and absent policies that would mandate a faster transition, it is unclear how the industry would get there. The vast majority of U.S. utilities have set midcentury goals to shift away from fossil fuels. And although many energy companies will retire coals plants in coming years, the U.S. power fleet expects to have more than 100,000 MW of coal generation operating in 2035.

The administration's climate strategy projects that carbon capture technology will mitigate emissions from still-existing fossil plants in the 2030s and 2040s. Nuclear generation would remain in operation and could see growth during the same time period. Absent from the plan are specific policies or regulations many say are needed to transition the $23.2 trillion U.S. economy away from fossil fuels.

After weeks of tough negotiations in Congress, the latest version of the Build Back Better legislation Biden has pushed includes $555 billion for climate and clean energy investments. That is almost as much as House Democrats called for in their original $3.5 trillion plan that has since been scaled back to $1.75 trillion.

"My Build Back Better framework will make historic investments in clean energy, the most significant investment to deal with the climate crisis that any advanced nation has ever made," Biden told COP26. "We'll demonstrate to the world that the United States is not only back at the table but hopefully will lead by the power of our example."

Tough sell in divided Congress

The Build Back Better spending plan no longer includes Biden's signature program for weaning the power industry off fossil fuels by 2035. The clean electricity payment program would have rewarded utilities for boosting their clean electricity supplies by 4% annually and penalized those that would not.

The initiative faced opposition from some energy trade groups and from Sen. Joe Manchin, D-W.Va., a staunch defender of his state's coal industry. Manchin has been able to control the negotiations with Democrats who cannot afford to lose a single vote in the upper chamber.

The administration is addressing climate change on different fronts, including through regulations and what it calls a "whole-of-government" approach involving all federal agencies. In the next day or two, the administration is expected to announce tough new rules for the oil and gas industry to rein in methane emissions, a potent greenhouse gas.

The administration also unveiled a plan Nov. 1 for how the U.S. will step up efforts to help vulnerable nations adapt to climate change and an update to the United Nations about U.S. climate progress over the past five years.

"President Biden recognized the need to increase support for adaptation, which is already costing developing countries an estimated $70 billion a year," Ani Dasgupta, president and CEO of the World Resources Institute, said in a statement, noting that the U.S. has yet to balance adaptation support with investments in emission mitigation. "This will be a boost to the adaptation movement globally."

In addition, the strategy lays out plans and projections for how the transportation, building, agriculture and industry sectors will reach net-zero by 2050 using a mix of regulations, market forces and congressional budget authority. Biden has set a target to have all new light-duty cars sold in the U.S. be electric by 2030, an ambitious goal with electric vehicles accounting for just 2% of the market today.

The transportation sector is the largest source of emissions in the U.S.