The perfectly green electricity grid sought by Joe Biden isn’t the end of the fight against global warming. It’s the beginning.
Today, 40 percent of America’s electricity comes from carbon-free sources. The Democratic presidential candidate has made getting that to 100 percent by 2035 a centerpiece of his $2 trillion plan to address climate change and create jobs. Getting there would take an enormous expansion of solar and wind capacity in the U.S., backed by mass adoption of energy-storage technologies and hanging onto existing hydroelectric and nuclear plants.
Policy experts question the 15-year timetable for eliminating emissions from the electrical system, which would indeed be an immense challenge. About a quarter of all U.S. emissions today come from electricity production, according to the U.S. Energy Information Administration. Even California, which launched an all-out push to decarbonize its grid in 2002, set 2045 as its goal. The state also has some of the nation’s highest electricity prices, although renewables are only one reason why. Sweden and Austria both set all-renewables goals to be met within the next 20 years, but they’re also both small and have grids that are already plenty green.
However, many of those same policy experts also agree that a clean grid is an initial leap that will make many other necessary steps possible, helping reduce emissions from transportation, industry, and buildings.
"I call it the first linchpin,” says Leah Stokes, an assistant professor of political science at the University of California, Santa Barbara who researches electric utilities. "As the electricity system cleans up, it unlocks other sectors more easily.”
Not everything could run on clean electricity, at least not immediately. Solar and wind alone may never be able to generate enough energy consistently to power a steel furnace or cement plant, for example, and neither passenger jets nor container ships are ready to be electrified. But the availability of cheap, emissions-free electricity would set off ripple effects throughout the economy, bringing within reach other solutions that once seemed impracticable.
Take the promise of hydrogen. As a fuel, it burns hot and clean, making it an ideal energy source for heavy industry. Right now, hydrogen is produced mainly by splitting hydrogen atoms from natural gas — an emissions-heavy process. If it were its own country, the global hydrogen industry would rank sixth in greenhouse gas emissions, according to 2017 data from energy research firm Wood Mackenzie. "It’s like the size of Germany,” says Merrian Borgeson, staff scientist at the Natural Resources Defense Council environmental group. "Just cleaning that up would be tremendously powerful.”
If those fossil-fuel-powered plants were replaced by ones that use cheap, abundant solar energy to extract hydrogen from water, clean hydrogen could be used to run factories or power plants that now rely on gas, oil or coal. This so-called "green hydrogen” currently supplies less than 1 percent of the world’s energy needs, according to a report by BloombergNEF. But by 2050, hydrogen from all sources could meet 24 percent of the world’s energy needs, while the price of green hydrogen could fall to just $1 per kilogram in some of the world’s largest markets, making it competitive against even fossil fuels.
Then there are all the things that can be powered by electricity but usually aren’t. Cars and trucks are the most familiar examples, but workarounds for gas in stoves and building-wide heating systems are already available, practical and affordable. Electrifying these things is a start, but to hold warming below the 2 degree Celsius threshold prescribed by the Paris climate agreement, that electricity also has to come from a carbon-neutral source.
With a cheap, green grid it might even become possible to suck carbon dioxide straight out of the atmosphere using a nascent technology called direct air capture. Future scenarios modeled by climate scientists in which warming is limited 2 degrees C almost always rely on these negative-emissions technologies. Early versions of direct air capture available today need vast amounts of energy, and using fossil fuel only releases more emissions, defeating the purpose.
Just by cleaning up emissions from transport, the electrical grid, and buildings, says Stokes, "we can get the vast majority of this problem done.”
There are, of course, complicating factors. The benefits of a green grid come only if carbon-free electricity is inexpensive. While renewable energy sources like wind and sunshine are free, building capacity for wind farms and photovoltaic plants isn’t. That’s particularly true if it’s done in a hurry. Biden’s clean-grid proposal doesn’t detail how its $2 trillion of spending will be allocated, which means there’s no way to tell if the investment in cleaning up the grid will be large enough to meet the 2035 deadline.
"It would be an unprecedented nation-building effort, the type of thing we haven’t seen since the New Deal and the Work Progress Administration,” says Jesse Jenkins, an assistant professor at Princeton University’s Department of Mechanical & Aerospace Engineering. "It took us 100 years to build the current grid.’’
But Biden’s goal isn’t far from estimates supported by researchers. A recent study from the Goldman School of Public Policy at the University of California Berkeley determined that the U.S. grid could use existing technologies — solar, wind, nuclear, hydroelectric dams, and batteries — to supply 90 percent of its electricity needs by 2035. Existing natural gas-fired plants would still be needed to cover the rest, the researchers found.
Sonia Aggarwal, vice president at nonpartisan energy and environmental policy firm Energy Innovation and a member of the technical review committee behind the study, says the idea was to explore pathways that maximize clean energy while keeping power prices at or below their current levels. Skeptics have been proven wrong in the past, she says. "People thought the grid would break at 30 percent (renewable energy) and prices would hockey-stick. We’ve seen grids that have pushed well past that.”
How to get from 90 percent clean power grid all the way to 100 percent might require a rapid ramp-up in some niche technologies. "There is clearly an opportunity five to 10 years from now to displace the last 10 percent of the carbon emissions out of the electric sector by manufacturing hydrogen with renewables,” said Jim Robo, chief executive officer at electric-utility giant NextEra Energy Inc., during an earnings call last week. The company also announced plans to run one of its Florida power plants on green hydrogen.
Biden’s clean energy proposal would also face political resistance. It calls for shifting energy use in buildings away from natural gas, an idea already being pursued in many cities that has been fought every step of the way by the gas industry. Restaurateurs have also opposed gas restrictions since many chefs refuse to cook with electric. And while American drivers have eagerly snapped up electric vehicles made by Tesla Inc., they’ve shown far less enthusiasm for plug-in cars from other manufacturers .
Market forces could work against a push for a 100 percent clean grid, no matter how cheap renewables become. "As you drive substitution for gas or oil, it can make substitution harder,” says Jenkins, the Princeton professor. If a plan like Biden’s manages to push some gas plants off the grid, for instance, falling demand for natural gas could create lower prices. That would making the process of cleaning up buildings or heavy industry all the more difficult.
And yet, using federal policy to spur clean-tech innovation has the potential to create breakthroughs that would cut seemingly intractable sources of emissions. A green grid could help shift the chemical industry away from fossil fuels as raw materials for their products. Renewables would be used to break water, carbon dioxide, or other compounds into building blocks that could then be reassembled into useful products.
"Even if you go to clean energy for power plants and vehicles, we still use lots of hydrocarbons to make things,” says Daniel Kammen, director of the University of California, Berkeley’s Renewable and Appropriate Energy Laboratory, who formerly served as renewable power specialist at the World Bank. Many of these processes start to become cost effective when renewable power reaches about 4 cents per kilowatt-hour, he says. Some new solar and wind facilities can already hit that price point. "The low cost of renewables means we could get off of that. This is an opportunity to build better compounds at lower cost.”
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