Natural gas - invisible renewable

For the longest time I thought natural gas was a fossil fuel that would eventually be depleted.  This would be unfortunate because it is the cleanest fossil fuel around.  Many of our coal burning power plants are now switching to natural gas as a cleaner solution, and the conversion of vehicles to CNG (compressed natural gas) reduces tailpipe emissions by more than 21%.

Then I discovered that natural gas is refined methane gas.  Methane is formed in landfills, sewage systems, and farms; and all of it can be captured and sold as fuel.  Unfortunately, much of the methane we generate is lost to the atmosphere where it behaves as a powerful greenhouse gas.  This is important to know when we consider that the largest single U.S. source of methane emission is the natural gas system itself!  All of these wells, processors, and pipelines offer endless opportunities for leaks.  We would never settle for leaky oil pipes, so we should set the same standards for leaky gas systems.  Invisible or not, natural gas leaks still impact the environment.

The capture of methane is considered by the EPA to be possibly the greatest opportunity to cut greenhouse gases.  Methane is 25 times more potent than carbon dioxide as a greenhouse gas, and it has only 1/8^th of the atmospheric lifespan (12 years as compared to CO2’s 100 years).  Consequently, a significant cut in carbon dioxide emission would not be felt for a century while a significant cut in methane would show results in just over a decade.  Moreover, methane is a commodity that provides an incentive for capture, but reduction of CO2 results in cost increases.  Fortunately, current efforts to capture methane have kept annual emissions flat over the last 20 years despite growth in gas exploration, population, and GDP.

After natural gas systems, the second largest source of U.S. methane emission comes from the raising of animals for meat.  The grass that is eaten by animals creates methane in the digestive tract.  This has improved as researchers apply genetic engineering to both the animals and their food sources.  Consequently, according to the EPA, cattle in feedlots are easier on the environment than free range cattle are.  This occurs because the food source is engineered for higher digestive efficiency, and the resulting manure can be managed for methane capture.  Combine these efforts with genetic engineering for heavier animals, and the methane output per pound of meat is reduced each year. 

Surprisingly, another significant source of agricultural methane comes from a seemingly benign source.  Rice production requires great quantities of fresh water lying in rice paddies.  This ponding water generates methane.  Although work is being done to decrease and capture the methane from farm animals, pipelines, and landfills; very little has been done to control or capture methane from rice production. As a result, world methane emissions from rice rival the world’s garbage dumps.  This demands attention since rice is among the most common staple foods.

Natural gas (methane) is currently our most promising source of clean burning fuel.  As we continue to improve our methods of capturing and controlling it, we create a long term solution to a cleaner future.  It is local, storable, transportable, abundant, clean burning, and renewable.  All we need to do is capture it.  So what can you do?  Write your congressman about tightening the requirements for leak monitoring in natural gas systems.  Then eat less meat and rice.  The planet will thank you.

Tony F.