Yergin, the chairman of IHS Cambridge Energy Research Associates in Washington, spends a lot of time thinking about energy. He won the Pulitzer Prize in 1992 for a history of the oil industry, The Prize. He is promoting his latest book, The Quest, a comprehensive examination of energy.
So after taking five years to write an 800-page book that explores everything from wind turbines to electric vehicles, is Yergin convinced we're stuck with greenhouse-gas-producing fuels?
"I'm convinced there will be major changes," he said. "But given how massive the energy system is, how complex it is, things just don't happen overnight."
Existing energy systems contain an enormous amount of embedded capital. New technologies have long lead times. Automobile fleets take a decade to turn over. And world energy demand is expected to grow 35 to 40 percent by 2030.
Wind turbines, after decades of development, are only now cost-competitive, he said. Photovoltaic cells, first used in spacecraft in 1958, still require subsidies.
"It's not a light switch where you can go from one to another," he said.
Yergin's long-term perspective comes out of his experience as a historian.
He is a skeptic of "peak oil" theorists, who believe the world is heading toward a catastrophic plunge in petroleum production. He said that the world has survived four previous pronouncements of the end of oil, starting with the 1886 prediction by the Pennsylvania state geologist that oil was "a temporary and vanishing phenomenon."
Yergin says that peak oil advocates don't take into account improvements in extraction technologies and efficiencies in consumption that often arise during periods of rising prices and shortages.
"Over the years, I've come to have more respect in the ability of markets to adjust," he said. "Well-functioning markets are part of your arsenal in energy security measures. But it's hard during a crisis because you have all the drama, you have the gas station on TV that has just run out of gasoline, and panic."
After Hurricanes Katrina and Rita shut down much of the Gulf Coast oil and gas production in 2005, there was no shortage of dire predictions about energy shortages. But the government temporarily relaxed regulations on motor-fuel blends, and supplies rebounded.
Likewise, exploration companies using hydraulic fracturing techniques have discovered oil in shale in Texas and North Dakota, adding new reserves into the mix.
"I don't know why [peak oil advocates] are so emotional about this issue," he said. "It's just an analytic question. . . . U.S. oil supply is up 10 percent since 2008. We're not necessarily low-cost oil, but new sources of oil are coming in."
Yergin is a member of a Department of Energy panel that examined the production of natural gas from deep formations like Pennsylvania's Marcellus Shale. The committee in August called for improvements to hydraulic fracturing, but disappointed anti-drilling activists by endorsing shale-gas development.
"Shale gas has come on really fast," said Yergin. "But people don't realize it's 30 percent of our gas production. It's not a question of whether to do it or not. It's happened."
Yergin does not directly take sides in the debate over climate change. But his book explores how the concern of a few scientists about the global consequences of burning fossil fuels developed into a powerful worldwide political issue over a few decades.
"I'm not a climate scientist, but I certainly recognize where the scientific consensus is," he said.
But Yergin is also a student of politics, and in polarized Washington, he has observed a "pretty dramatic" erosion of support for climate legislation driving some demand for renewable energy.
"This is not on the political agenda now," he said. "It's all about jobs and the economy."
Contact staff writer Andrew Maykuth at 215-854-2947, email@example.com,
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