tech in your tank

new ways of making fuels are helping save energy and reduce greenhouse gas emissions.

July 19, 2007

Most of the greenhouse gas emissions associated with each gallon of fuel come from driving, so motorists play an important role in reducing emissions. Maintaining your vehicle, watching your speed and sharing rides can help. More efficient engines can also make a significant difference, as we described in the previous op-ed in this series.

But some greenhouse gases (GHG) are emitted even before you start your engine. They come from producing, manufacturing and delivering the fuel. This is where companies like ExxonMobil are taking the lead. By applying new technologies and more efficient operating practices at our facilities, we are working to reduce greenhouse gas emissions.

Since the launch of our Global Energy Management System (GEMS) in 2000, we have identified steps to improve energy efficiency at our refineries and chemical plants by 15 to 20 percent, and we have already implemented over half these improvements. As a result of these actions, ExxonMobil avoided about 8 million metric tons of greenhouse gases in 2006, roughly equal to taking about 1.5 million cars off U.S. roads.

An example of this can be seen at our refineries, where we are working to reduce emissions from "flaring" — the burning of gases that are generated as a result of maintenance or unexpected operating events. By following best practices and putting in place tighter controls, last year ExxonMobil reduced flaring at our refineries by over 10 percent.

At about 100 facilities worldwide, we are also applying a process called "cogeneration" — the simultaneous production of electricity and thermal heat/steam. With the latest turbine technology, cogeneration can be twice as efficient as traditional methods of producing steam and power separately. ExxonMobil's current cogeneration capacity reduces global carbon dioxide emissions by over 10.5 million metric tons annually, of which over 4 million metric tons are due to cogeneration investments made since 1999 (see chart). That's like taking close to another 2 million cars off U.S. roads.

Greenhouse gases are not the only emissions we are working to reduce. Through new technologies, investments and practices, we have reduced emissions of sulfur dioxide, nitrogen oxides, and volatile organic compounds from our operations worldwide by about 16 percent from 2003 levels.

Meeting the world's growing demand for transportation energy while also protecting our environment is an enormous challenge. And it is the technology — and the commitment — that goes into the fuel in your tank that can help meet it.