REDUCING OUR ENVIRONMENTAL FOOTPRINT NATURAL GAS A SOLUTION?

The “great moral crusade” of this generation paraphrasing Al Gore is to reduce our environmental footprint. Everyone agrees but we all disagree on the path forward.

Despite all the recent critics, the U.S. had reduced in the past 18 months its energy-related emissions. The emissions were at their lowest level since 1991, having fallen about 13% since their peak in 2007. The main reason for this dramatic fall is the increased use of natural gas. However, is it a good thing? As natural gas burning is definitively better than coal but drilling is challenging with methane emissions.

Natural gas is a fossil fuel, though the global warming emissions from its combustion are much lower than those from coal or oil. Natural gas emits 50 to 60 percent less carbon dioxide (CO2) when burn in a new, efficient natural gas power plant compared with emissions from a typical new coal plant. Emissions, do not tell the full story.

The drilling and extraction of natural gas from wells and its transportation in pipelines results in the leakage of methane, primary component of natural gas that is 30 times stronger than CO2 at trapping heat, thus contributing to global warming.

Whether natural gas has lower life cycle greenhouse gas emissions than coal and oil depends on the “assumed” leakage rate, the global warming potential of methane over different time frames, the energy conversion efficiency, and other factors. Technologies are available to reduce much of the leaking methane, but deploying such technology would require new policies and investments. Such policies need to be put in place quickly as we see the drilling and extraction of natural gas flourishing in our country.

Cleaner burning than other fossil fuels, the combustion of natural gas produces negligible amounts of sulfur, mercury, and particulates. Burning natural gas does produce nitrogen oxides (NOx), which are precursors to smog, but at lower levels than gasoline and diesel used for motor vehicles.

DOE analyses indicate that every 10,000 U.S. homes powered with natural gas instead of coal avoids the annual emissions of 1,900 tons of NOx, 3,900 tons of SO2, and 5,200 tons of particulates. Reductions in these emissions translate into public health benefits, as these pollutants have been linked with problems such as asthma, bronchitis, lung cancer, and heart disease for hundreds of thousands of Americans. (DOE website)

However, despite these benefits, unconventional gas development can affect local and regional air quality. Some areas where drilling occurs have experienced increases in concentrations of hazardous air pollutants and two of the six “criteria pollutants” — particulate matter and ozone plus its precursors — regulated by the EPA because of their harmful effects on health and the environment. Exposure to elevated levels of these air pollutants can lead to adverse health outcomes, including respiratory symptoms, cardiovascular disease, and cancer.

The United States needs to be at the forefront of these technologies to avoid a surge in methane emissions. This is probably the next big challenge to reduce global warming. The Technology exists but investments needs to be made, thus regulations need to be put in place quickly. The EPA is listing several of such technology on its website (https://www.epa.gov/natural-gas-star-program/recommended-technologies-reduce-methane-emissions).