This posting originally appeared in the National Journal’s Energy and Environment Expert Blog.

With the global explosion of unconventional gas production, reports of the death of the fossil fuel economy are, to paraphrase Mark Twain, greatly exaggerated. Gas may not stay at its current extraordinarily low price, but the market landscape seems to be altered for quite some time.

The explosion of low-cost shale gas reserves is a two-edged climate sword. Generating electricity with gas is 30 to 50 percent less carbon-intensive than coal when leaks and releases of methane, the main component of natural gas, are accounted for. (For other uses like vehicle fuel, we haven’t seen any evidence that gas is better than other fossil fuels, and if vehicles leak even a small amount, natural gas could be worse than gasoline). But even for electricity, gas is still a high-carbon fuel: replacing all coal-fired generation with gas would get us only part of the way to the 80 percent CO2 reduction needed by mid-century. Moreover, new gas plants are more likely to displace new zero-carbon generation sources than to displace existing cheap coal plants. Carbon dioxide emitted to the atmosphere stays there, causing warming, for many centuries. By some estimates, the amount of CO2 already emitted has committed the world to warming in excess of 2 degrees Celsius, which is well outside human experience; to hold the increase to 3-4 degrees might well require zeroing out carbon emissions by mid-century.
Read the rest of this entry »