Speed Dial: Marvin Odum

The Shell Oil president talks about why he's for a carbon cap, his biofuels play in Brazil, and how long it will take to scale up clean energy

The push for climate legislation went off the rails this year. What will accelerate the transition to clean energy if the U.S. is not going to have a price on carbon?

We have for years advocated an economy­wide, market-based [cap]. In the absence of that there are some things we can do. For example, we have a price on carbon inside of Shell. We charge ourselves $40 per ton for CO2 emissions. That changes the way we think about the business. We're focusing on natural gas, because it's the way you can have the most immediate impact on reducing emissions.

In Brazil, your $12 billion joint venture with Cosan is making a big bet on ethanol from sugar cane.

About 2 billion liters a year. It will make us one of the biggest ethanol producers in the world. On a [life cycle] basis, we see a CO2 reduction of 90 percent. We're working on a full suite of second-generation biofuel technologies, and the joint venture lets us attach these technologies to an existing commercial-scale operation.

How long will it take for cellulosic ethanol to be economically viable?

Historically, it takes about 30 years for a new energy to represent 1 percent of total energy supply. I'm not saying it has to be that way; you can change it through government policy. Conventional biofuels are just now getting to 1 percent. We've been working on advanced biofuels for a good part of the last decade, but it could be 10 years or more before you see it in a very real way. A price on carbon is the one thing that really kick-starts all of this on a massive scale.

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