An MIT study group has issued a report on the future of natural gas, reaffirming that gas will play a "a crucial role" in reducing U.S. carbon emissions in the next decades. Two months ago, the Worldwatch Institute noted that gas already is displacing dirty coal in the United States, and that U.S. greenhouse emissions have dropped sharply in recent years as a result. Substituting state-of-the-art gas generation for obsolete coal generation can reduce carbon emissions "by a factor of three," notes Ernest J. Moniz, head of the MITÂ unit that produced the gas report and the former top scientist in the Clinton Administration's energy department.
MIT notes that because the United States has a large amount of excess natural gas generating capacity, gas can immediately contribute much more to electricity supplies without new power plants having to be built--a point Robert F. Kennedy Jr also has been pressing in recent years. "The overbuilding of natural gas combined cycle plants starting in the mid-1990s presents a significant opportunity for near-term reductions in CO2 emissions from the power sector," says MIT. "The current fleet of natural gas combined cycle units has an average capacity factor of 41 percent, relative to a design-capacity factor of up to 85 percent."
In other words, the present-day fleet of U.S. gas-fired power plants could be generating twice as much electricity as they currently do. In Texas's ERCOT electricity system, MIT found, substituting gas for coal could reduce CO2 emissions 22 percent without adversely affecting reliability, while also cutting sulfur and nitrogen pollutants.
What makes that kind of scenario not merely conceivable but a likely prospect is the rapid development of U.S. "unconventional gas" by means of hydraulic fracking. MIT concurs with the new estimates finding that the United States has enough gas to last at current consumption rates for close to a hundred years. Globally, even without taking unconventional gas and innovations in extraction technology into account, the world has enough gas for 160 years, says MIT.
MIT finds that concerns about water are the one factor that could stand in the way of gas, echoing Spectrum's conclusions in a recent feature article. MIT recommends that full disclosure of fracking fluids be required, and that integrated water usage plans be prepared in regions where fracking is intense. The MIT report agrees with Kennedy that regulation should favor substitution of gas for coal. It agrees with the gas industry that where intermittent wind or solar generation is installed, there should also be additional investment in new gas generation, as a backup.
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