If international goals to lower the global mean temperature by 2050 are to be met, fossil-fuel-burning power plants, vehicles and more will have to be retired sooner rather than later, according to a UC Irvine-led study.
“We need to reach net-zero carbon dioxide emissions by mid-century to achieve stabilization of global temperatures as called for in international agreements such as the Paris accords,” according to the study’s lead author, Dan Tong, a UCI postdoctoral scholar in Earth system science. “But that won’t happen unless we get rid of the long-lasting power plants, boilers, furnaces and vehicles before the end of their useful life and replace them with non-emitting energy technologies.”
The study, published Monday in the science journal Nature, states that “committed” emissions — referring to future emissions that will occur in the normal lifespan of existing infrastructure — would account for two-thirds of the carbon budget set forth by the Intergovernmental Panel on Climate Change to limit global warming to 2 degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial levels over the next three decades. Committed emissions would take up the entire carbon budget if nations limited warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit), the study says.
The Paris Agreement, an international accord to combat climate change that took effect in November 2016, reflects both numbers.
The UCI-led study projects existing infrastructure will release an estimated 658 gigatons of carbon dioxide into the atmosphere if operations continue as usual. More than half the emissions, the study states, are projected to come from the electricity sector, with the United States accounting for about 9%, the European Union 7% and China 41%.
An additional 188 gigatons are expected if planned power plants are built.
Over the past year, researchers looked to data sets of global power plants, their ages, locations, the fuels burned and annual emissions. Steven Davis, a UCI associate professor of Earth system science, said the team also examined steel and concrete plants and vehicle sales dating to the 1970s.
Researchers assumed that power plants and industrial boilers will operate for about 40 years and that light-duty vehicles typically will be on the road for 15 years, according to UCI. They also tested different lifetime assumptions to see how early that carbon dioxide-emitting infrastructure might need to be retired to meet international climate goals. For example, a 1.5-degrees Celsius boost in mean temperature might be avoided if current power plants were shuttered after 25 years of operation, rather than 40, the study states.
The study is a follow-up to a paper that Davis wrote a decade ago with Ken Caldeira, an atmospheric scientist at the Carnegie Institution for Science’s department of global ecology and a collaborator on the new project.
Caldeira said that at that time, research showed there wasn’t enough infrastructure to pass the 1.5-degree mark. But in the past decade, the global number of fossil-fuel-burning power plants and vehicles has increased dramatically, driven by economic and industrial development in places such as China and India, according to UCI.
Locally, power plant operator AES reported in June that construction was 88% complete on its new plant in Huntington Beach, which is to replace the 1950s-era seaside power plant at 21730 Newland St. The new plant, which is expected to go live in 2020, will use 50% less fuel to deliver electrical service, which will lead to lower carbon emissions, according to the company.
Stephen O’Kane, director of sustainability and compliance for AES US West, said he agrees with the conclusions of the UCI study and said that to meet the climate budget, fossil fuels will need to be relied on less. O’Kane said it is important to look not only to the Huntington Beach power plant but to changes being made at large.
“On a net basis, we will be 100% renewable energy. We can get there. But we’ll still probably need fossil fuels in certain areas to meet specific people, specific conditions and specific needs,” O’Kane said. “The thing with electricity is that you have to serve people all the time … and that gets tricky. How do you get to people in rural or constrained areas?”
O’Kane said most plants will be near the end of their lifespans by 2050. By then, he said, power plants burning fossil fuels should be used only to fill gaps in service where renewable energy cannot.
Caldeira said “there’s been an uptick in renewable energy — less in coal plants and natural gas plants. But emissions keep going up and going in the wrong direction. That’s sort of the glass half-empty. The glass half-full view is that most of the emissions projected for business-as-usual scenarios for the rest of this century come from technology that don’t now exist.”
Caldeira said it is a choice as to whether the targeted temperature thresholds are met.
“If we go beyond [1.5 degrees], it’s because we chose to build more automobiles, more power plants, etc.,” he said. “So it’s still within our control. If we were business as usual, people would expect something like a rise of 4 degrees Celsius by end of the century. In that whole space between 1.5 and 4, there’d have to be a whole lot of things we haven’t built yet.”
Brian Maas, president of the California New Car Dealers Assn., said the organization is for the promotion of alternative-power vehicles. But it also is supportive of consumer choices, he said.
“Our preference as a retailer is we sell the kinds of vehicles that our customers want to buy, and roughly speaking, 95% are internal combustion engine cars,” Maas said. “To get us … to zero emissions ... is going to take a dramatic shift in consumer behaviors, incentives offered by the government in the private sector, availability, charging infrastructures, etc. That’s not to say the goal is impossible or isn’t worthy, but it’s not going to be easy.”
“In order to get folks behind such an exponential change, we’ve got to lay the groundwork for that,” he added. “But we’re a long way from getting to a place from saying that we’re going to eliminate all power plants emitting carbon by 2050. It’s certainly a great goal, but the challenge is, what’s our path to get there?”
Davis said the study isn’t meant to say the planet is “screwed.”
“What I really want people to take away is that if we like these targets and feel this is what we should be aiming for, it’d require not only that we stop building fossil-fuel infrastructure but that we retire some of what we already have before the end of its useful life,” he said.