What Are We Missing?

Gilbert Metcalf

Professor of Economics, School of Arts & Sciences

We need to come to grips with the fact that coal is extraordinarily abundant and very inexpensive. Much of the discussion around a carbon policy just assumes that we are going to somehow wean ourselves from coal. And I think that's simply unrealistic.

Coal provides over half the electricity in the United States, and that's projected to go up to 60% by 2030, according to the Department of Energy. The United States has one quarter of the world's reserves of coal, more than any other nation in the world. Coal is easy to get out of the ground, a fact that contribues to its low cost. We consume 20% of the world's coal, and we're second only to China, which of course is the next problem: they're consuming 40% of the world's coal, and their consumption is growing at about 9% a year. So worldwide, we've got a huge demand for coal, and of course the problem is that this is the highest source of carbon per unit of energy of any of our fuel sources. In this country coal is responsible for one-third of our carbon emissions.

"Much of the discussion around a carbon policy just assumes that we are going to somehow wean ourselves from coal. And I think that's simply unrealistic."

Once you acknowledge that coal is the elephant in the room here with climate policy, there are four important questions. The first is how we're going to burn coal without releasing carbon into the atmosphere. Technologies for carbon capture exist, though none have ever been used at the scale we're going to need. And meanwhile, we've got new coal plants coming online that are not set up for carbon capture. And so the second question is, how are we going to get the technology to store carbon incorporated in existing plants? The third question is how do we store the carbon once we capture it? Again, we know that the technology exists but what we don't know is whether it works at the kind of scale we're going to need. We also face some difficult legal and regulatory problems. For example, who is liable in the long-run if carbon leaks out of the storage sites? And finally, we need a whole transportation network to move the carbon that we capture from coal-burning plants to storage sites. So we'll need a national network of pipelines that's comparable to our network of natural gas pipelines. This raises all kinds of interesting economic and political issues, because we'll need a national regulatory structure that's capable of dealing with establishing that national network across state boundaries. This is really more a political and regulatory problem than it is a technical problem.

"It's clear that people don't understand that over half the electricity we consume in this country comes from coal."

It's clear that people don't understand that over half the electricity we consume in this country comes from coal. If you ask people, they typically will say oil is a key source for electricity, and in fact oil only provides about 3% of the electricity in this country. So there's a real disconnect between where people think electricity comes from and reality. I don't think people connect the dots and realize just how important coal is in the world economy.

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Interviews by Georgiana Cohen, Office of Web Communications

Homepage photo by John McConnico / Associated Press. Tseng photo by Melody Ko, University Photographer. Islam, Metcalf, Rappaport, Reed and Shimshack photos by Alonso Nichols for Tufts University. Portney photo by Zara Tzanev for Tufts University. Kirshen photo by Aaron Schutzengel (A'07) for Tufts University. Najam photo by Brian Loeb (A'06) for Tufts University.

This story originally ran on Oct. 22, 2007.