Natural gas will not be able to significantly reduce the release of carbon dioxide into the atmosphere, according to a new study.
The United States possesses vast amounts of natural gas, which some developers believe could replace fossil fuels for some uses. The gas releases just half of the amount of carbon dioxide produced by coal, for a given amount of energy.
University of California, Irvine (UCI) researchers examined the environmental benefits of burning natural gas compared to oil and other fuels. The team worked with researchers from the non-profit group Near Zero.
"We asked natural gas experts for their estimates of natural gas supply curves - the total amount of natural gas available in the U.S.... [W]e then modeled the effect of varying natural gas supplies on the U.S. electricity mix, as well as the resulting greenhouse gas emissions. We also looked at four different scenarios for climate policies: no policy, a moderate carbon tax, a stringent cap on emissions, and a requirement of 50% renewable electricity by 2050," the group wrote in a press release announcing the study.
The researchers found that when supplies of natural gas were high, less coal was utilized, but demand for renewable energy also declined. The only scenario examined in the study, which favored renewable energy under all conditions, was the 50 percent renewable energy mandate by 2050. Without such an agreement, reduction in energy use from renewable sources offset any savings in greenhouse gas emissions from the use of natural gas.
The study assumes 1.5 percent of the gas would be lost during production and transport of the fuel.
Like oil and its derivatives, including gasoline, natural gas is a fossil fuel, created long ago from the remains of ancient plants and animals, exposed to tremendous heat and pressures over the course of thousands of years. The gas is a mixture of several substances, primarily methane, along with nitrogen, carbon dioxide and hydrogen sulfide, which is responsible for the smell of rotten eggs. Like other fossil fuels, the substance is not renewable.
The study concludes that although a switch from other fossil fuels to natural gas could have some limited environmental benefits, renewable energy may suffer in the long term.
"Cutting greenhouse gas emissions by burning natural gas is like dieting by eating reduced-fat cookies. It may be better than eating full-fat cookies, but if you really want to lose weight, you probably need to avoid cookies altogether," Steven Davis, assistant professor of Earth system science at UC Irvine, said.
Study of natural gas and its effect on emissions of carbon dioxide was detailed in the journal Environmental Research Letters.
