Fresh Ideas: Natural gas is a bridge to alternative power in future

I remember the oil wells of my childhood: those rhythmic nodding pumps that didn’t look at all like the huge oil derricks spouting black oil in movies such as “Giant.”

And I remember phrases such as “the well ran dry” and millionaires who were (in the movies) now reduced to poverty. In the early 1970s, it seemed real life had finally caught up to the movies and the U.S. was finally running out of oil. But that wasn’t the case, exactly.

When social scientists (primarily economists) say “the world will never run out of oil,” what they mean is that at the present time extracting oil is too expensive, but when technology has improved to make it profitable to extract, it will be available. Looking at it this way, the size of an “oil reserve” depends on the technology able to access it. Physical scientists, on the other hand, define an “oil reserve” based on the number of hydrocarbon molecules in the ground — and those are finite.

Typically, we hear more from economists than physical scientists on this subject because those who study economic recessions see a corollary (historically) between economic growth and energy use. In other words, when energy consumption is up, so is economic output. So, becoming “energy-independent” has international ramifications, not merely national ones.

As if this were not enough, the language of oil can create its own murky goo. The umbrella term for all nonsolid hydrocarbons is petroleum, which includes natural gas, propane and oil of various types, as well as designators for oil that is hard to get (“tight” oil) or oil that is obtained from a particular source (“shale” oil). And because oil production has changed, we have a new term, unconventional petroleum. This is oil (and/or gas) that used to be too difficult to get and therefore not worth messing with, but which technology is now accessing by hydraulic fracturing, or fracking. (Conventional petroleum is the oil we get from the Middle East.)

It’s the unconventional petroleum that is in the headlines these days. This petroleum is roughly of two types. One is heavier and less refined than crude oil, such as tar sands, and the infamous oil found underneath the subarctic forest in central Canada that would require a Texas-to-Canada pipeline and a proposed Montreal-to-British Columbia pipeline. Both have drawn protests. The other is lighter and more refined than crude oil and includes the natural gas from methane hydrate, also known as methane clathrate.

Methane hydrate’s big attraction is its abundance. Some estimates indicate there is twice as much of it as all other fossil fuels combined. Seemingly, this “reserve” could not be depleted for a long time. The U.S. Department of Energy has been funding a methane-hydrate research program since 1982, and samples have been recovered from continental shelf areas along our own Pacific Coast, in the Gulf of Mexico, and off the coast of Virginia. Other nations, particularly Japan, are interested.

Assuming that drilling, shipping, and the high cost of production are surmountable, the bottom line is that natural gas, the cleanest of all fossil fuels, is nevertheless a greenhouse gas itself, and far more potent than carbon dioxide. Methane, the major component in natural gas has a radiative forcing 20 times greater than that of carbon dioxide, which means it increases the severity of global warming. So, it becomes a question of amount. The more natural gas we burn, the faster we bring on global warming. It’s for this reason that scientists say natural gas is best thought of as a “bridge,” a temporary solution until we can harness solar, wind and geothermal power.

Ursula Carlson, Ph.D., is professor emerita at Western Nevada College and notes that the substance of her column is a summary of Charles C. Mann’s 12-page article published in this month’s issue of The Atlantic magazine.