First, the bad news: nothing is for free. Moving the global energy system away from fossil fuels to renewables will generate carbon emissions in and of itself, as building wind turbines, solar panels, and other new infrastructure takes energy—some of which necessarily comes from the fossil fuels we’re trying to get rid of. The good news: If this infrastructure could be brought online quickly, those emissions would drop dramatically, because more renewable energy early on would mean far less fossil fuels required to power change.
“The message is that it will take energy to rebuild the global energy system, and we need to account for that,” said lead author Cory Liske, who conducted the research as a PhD student. Student at Columbia School of Climate’s Lamont-Doherty Earth Observatory. “Whichever way you do it, it can’t be neglected. But the more you can bring in renewables in the beginning, the more you can transition with renewables.”
The researchers calculated the potential emissions from energy use in mining, manufacturing, transportation, construction and other activities needed to create massive farms of solar panels and wind turbines, along with more limited geothermal infrastructure and other energy sources. Previous research has projected the dollar cost of new energy infrastructure — $3.5 trillion annually through 2050 to reach net zero emissions, according to one study, or as much as about $14 trillion for the United States alone in the same period, according to another. The new study appears to be the first to project the cost of greenhouse gases.
At the current slow pace of renewable infrastructure production (it’s projected to lead to a 2.7°C warming by the end of the century), researchers estimate that these activities will produce 185 billion tons of carbon dioxide by 2100. That alone equates to five or six years of Current global emissions – a heavy burden on the atmosphere. However, if the world builds the infrastructure itself fast enough to limit the temperature rise to 2 degrees – the current international agreement aims to bring in that limit – those emissions would be halved to 95 billion tons. And if a really ambitious course is pursued, limiting warming to 1.5 degrees, the cost will be just 20 billion tons by 2100 — just six months or so off current global emissions.
The researchers point out that all of their estimates are probably too low. First, they don’t take into account the materials and construction needed for new electric transmission lines, nor batteries for storage—both energy- and resource-intensive products. Nor do they include the cost of replacing gas and diesel vehicles with electric ones, or making existing buildings more energy efficient. The study also looks at only carbon dioxide emissions, which currently cause about 60 percent of sustained warming — not other greenhouse gases including methane and nitrous oxide.
It is difficult to quantify other effects of the transition to renewables, but they could be significant. Not only would all of these new, high-tech devices require massive amounts of base metals including copper, iron, and nickel, but previously less used rare elements like lithium, cobalt, yttrium, and neodymium. Many commodities are likely to come from previously untouched places with fragile environments, including the deep sea, African rainforests, and rapidly melting Greenland. Solar panels and wind turbines will directly consume vast tracts of land, with potential attendant impacts on ecosystems and the people who live there.
“We’re setting the bottom line,” Lisk said of the study’s estimates. “The upper limit could be much higher.” But, he says, “the result is encouraging.” Given recent declines in the price of renewable technologies, Lisk said, 80 to 90 percent of what the world needs could be installed in the next few decades, especially if current subsidies for fossil fuel production are shifted to renewables. “If we take a more ambitious path, this whole problem will go away. It’s only bad news if we don’t start investing in the next five to 10 years.”
As part of the study, Liske and his colleagues also looked at carbon emissions from adaptation to sea level rise. They found that building seawalls and moving cities inland when necessary would generate 1 billion tons of carbon dioxide by 2100 under the two-degree scenario. This, again, will only be part of the cost of adaptation; They did not look at infrastructure to control inland flooding, irrigation in areas that might become drier, adaptation of buildings to higher temperatures or other required projects.
“Despite these limitations,” the authors write, “we conclude that the magnitude of CO2 emissions involved in the broader climate transition is geophysically and politically relevant.” “Transition emissions can be significantly reduced under faster-paced decarbonization, bringing new urgency to policy progress on the rapid deployment of renewable energy.”
Co-authors of the study are Dennis Schalla of Lancaster University, UK. Robin Kreckler and Antoine Levesque of the German Potsdam Institute for Climate Impact Research; Sogoris Sogouridis from Dubai Electricity and Water Authority; Catherine Mach of the University of Miami; Daniel Horin Greenford and H. Damon Matthews of Canada’s Concordia University; and Radley Horton of the Lamont-Doherty Earth Observatory. Corey Lisk is now a postdoctoral researcher at Dartmouth College.
Materials provided by Columbia School of Climate. Original by Kevin Krajek. Note: Content can be modified by style and length.