For the United States to remove carbon emissions from its energy system in 20 years, it would have to build new clean energy capacity at 10 times the rate it has built existing capacity, a specialist in problems of technology and public policy said Friday in Washington D.C.
Renewable energy is currently growing at about half the rate of traditional growth, according to the White House.
Even if the U.S. gives itself 60 years, it has to build new energy at 3 times the rate it has added capacity to the existing system, said M. Granger Morgan, who heads the Department of Engineering and Public Policy at Carnegie Mellon University and directs the Scott Institute for Energy Innovation.
"You could look at that and just say, 'Oh my lord,' give up and go home," Morgan told a lunchtime crowd at the Peterson Institute for International Economics, which was just wrapping up a conference on "China, the West, and the Alternative Energy Innovation Challenge." The luncheon talk was webcast.
"The point of showing you this picture is to say that we've got to get started now. We should have started 20, 30 years ago but if we don't get started the slope of those lines just get steeper and steeper," Morgan said.
"We've got a very serious problem and we need to stop fooling around and get with it, or our children and grandchildren are not going to like the world we leave them."
Last year, Princeton researchers argued that even if carbon emissions halted immediately, the earth will continue to warm for hundreds of years, passing the 2-degrees Celsius mark that climate scientists consider a dangerous threshold.
Morgan's estimates cover the entire energy system—not just electricity generation, but transportation, industry, agriculture, commercial and residential sources of greenhouse gas emissions.
The Environmental Protection Agency's proposed rule is much less ambitious—seeking a 30 percent reduction in carbon dioxide levels by 2030 in the electricity sector alone. To do that, the rule relies heavily on a shift from coal to natural gas, which emits less carbon dioxide than coal, but still emits carbon dioxide.
Decarbonizing the electricity sector is not nearly as daunting as cleaning up the whole system, Granger said. To decarbonize power plants in the next 20 years the U.S. has to build new, clean power sources at 1.5 times the rate it has added capacity in the past. Given 60 years, the U.S. can eliminate carbon emissions from power plants by building new clean plants at half the historical rate of plant construction.
That's roughly the current rate at which renewable generation is being added to the system, according to the White House, but those renewables are being added alongside natural gas plants that continue to emit carbon.
Wind and solar energy are joining the system at higher rates than ever, Granger said, but much more innovation is needed to give wind and solar a market advantage over natural gas:
"One really needs substantial not just science but also basic technology research in this space to get to a point that will allow these things to continue without massive government subsidies," Granger said.
The United Nations Framework Convention on Climate Change has set a goal to hold the increase in global temperature below 2°C — equated by scientists to a concentration level of 450 parts per million of carbon dioxide in the atmosphere, which many scientists say is already an unrealistic goal.
Few politicians are discussing complete decarbonization. President Obama has pledged to reduce U.S. greenhouse gas emissions 80 percent by 2050.
"I don't think most of the world realizes just how big the problem is of decarbonizing our energy system," Granger said. "I'm going talking about the U.S., but the problem is probably even bigger in the case of China."
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