I find it unfortunate that Randy Udall has suggested that natural gas, a fossil fuel, can save the world (HCN, 8/17/09). The implication is that the relatively recent discoveries about how to better exploit shale gas will be sufficient to meet a substantial part of our energy needs. The article gives citizens a false sense of security that leads them to ignore the really serious issue of climate change.
According to Naturalgas.org, the U.S. has an economically recoverable gas resource of about 1,800 trillion cubic feet, of which only about 270 trillion cubic feet (15 percent) is shale gas. Assuming that the U.S. currently consumes 24 trillion cubic feet/year, this amounts to a 75-year supply at present consumption rates. However, if natural gas is to meet current demand and additionally displace other fossil fuels, gas consumption will have to increase at an accelerated rate. At a growth rate of 5 percent, 1,800 trillion cubic feet would be consumed in about 32 years, not 75.
The more important issue is how we will deal with climate change. It is true that natural gas-fired combined cycle electrical generation produces approximately one-third the carbon dioxide per kilowatt hour as does coal-fired electrical generation. Natural gas is a great "bridging" fuel as we move away from coal. However, it is still a fossil fuel that will be pumping carbon into the atmosphere. The only sensible way to deal with climate change is to reduce consumption to the point that renewables (wind, solar, possibly geothermal, and biomass if done correctly) can meet our energy needs.
Jerry D. Unruh
Manitou Springs, Colorado