Why the oil-price collapse changes everything: Yergin

It was not long ago that $100 per barrel oil was accepted as the new normal. China's strong economic growth (and energy demand) would continue apace, and OPEC and Saudi Arabia would continue to play the traditional role as swing producer in support of oil prices. Events have proved otherwise.

Oil markets have entered a new period. Now it is supply, not demand, which is the key the factor, making not-so-distant discussions of "peak oil" seem very far gone. China's economy, while still growing, has slowed. And by leaving oil prices to the market, OPEC has effectively ceded the role of de facto swing producer to a country that hardly expected it—the United States.

Markets never cease in their ability to upend current expectations and confound established thinking. That is certainly the case for the world of energy in a year that has seen the rapid creation of new realities and overturned assumptions.

This is indeed a time of great turbulence and transition for energy. A convergence of major developments over the past year—led by the rapid oil-price collapse—has disrupted some of the most fundamental assumptions that were the basis for the long-term planning and investment that are essential to meeting the world's ever-growing need for energy.

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All of this amounts to what one might call an "era of new realism" for the energy industry—a period of recalibration and transition that calls for new thinking and ideas for managing and leading through the current cycle.

A turning point, or point of no return?

The theme for IHS CERAWeek 2015—our annual conference of global energy, policy and financials leaders that I am honored to chair—is this "turning point." It foreshadows profound changes throughout the energy spectrum, from oil-and-gas production to power generation, renewable energy and regulatory decisions.

It reflects a time of fundamental shifts and long-term considerations, such as how North America will adapt to its new role as the emerging swing producer, and to what degree are the critical choices facing the power industry, and what to expect later this year from the U.N. Conference on Climate Change.

Understanding these new realities and what they will mean for markets, geopolitics, investment, costs, the environment and strategy will be key to the energy challenges ahead. Harnessing the knowledge and foresight required to meet those challenges and seize the opportunities for the future will be the task of the global group of energy, policy, technology and financial leaders gathering this week at IHS CERAWeek 2015 and into the future.

By Daniel Yergin, vice chairman of IHS and author, most recently, of "The Quest: Energy, Security, and the Remaking of the Modern World." He is the chair of this week's IHS CERAWeek conference in Houston, bringing together more than 2,500 energy thinkers from 50 countries.