OPINION: Natural gas just part of US energy solution
Coal once produced more than 50 percent of America's electricity, but now it provides only 32 percent of the nation's power generation. This drop occurred without a carbon tax or a carbon cap-and-trade system like the one the Obama Administration tried to push through Congress three years ago. By replacing coal with cheaper natural gas that emits 60 percent less carbon than coal, we have achieved a 15 percent reduction in the amount of carbon dioxide we emit compared with 2007.
As a result, the rush is on to develop vast new reserves of natural gas trapped in shale rock. The productivity of a typical gas rig has increased as much as 300 percent in the past five years. In fact, some 50 Gigawatts of new natural-gas generating capacity are scheduled to come online by 2017. One Gigawatt is equal to the generating capacity of a large nuclear plant.
Heavy industry, particularly chemical manufacturers who use natural gas as a feedstock, are building new plants or expanding operations in the United States to take advantage of cheap natural gas. Long-haul truckers, city bus services and even trash companies are moving to convert their vehicle fleets to run on natural gas. The Honda Civic already comes in a natural gas version.
Homeowners in the Northeast are switching from heating oil to natural gas for winter heating. And since 2007, the share of the nation's electricity produced by natural gas plants has jumped from 21 percent to 30 percent. In addition, the Obama Administration has issued an LNG export license to one energy company and is expected to issue licenses to other companies, which could make the U.S. a significant LNG exporter by the end of this decade.
Companies and consumers will benefit if natural gas remains cheap, but historically the price of gas has been extremely volatile. In fact, last month the price of natural gas had more than doubled its value in 2012. We should therefore avoid an over dependence that would harm consumers and the U.S. economy.
Energy diversity is the best protection against wild swings in gas prices. And if we use more zero-carbon energy sources such as solar, wind, and nuclear power, we will also achieve faster reductions in greenhouse-gas emissions.
Natural gas alone will not bend the carbon curve fast enough. Moreover, additional leaks from pipelines, gas wells, etc. would be problematic since methane is 25 times more potent a greenhouse gas than carbon dioxide.
Today, solar and wind energy need further development to efficiently produce the amount of power that we need. Combined, they provide less than 2 percent of our electricity. Due to their intermittent nature and the lack of a mature energy storage technology, we burn natural gas to make up the difference between supply and demand.
Nuclear energy is another story. It already supplies around 20 percent of our nation's electricity, and it can grow to meet the demand for electricity well into the future. If the United States were to reprocess used nuclear fuel, we would extend our uranium resources indefinitely, reduce the amount of high-level radioactive waste that must be isolated in a deep-geologic repository, and reduce the amount of time for said isolation.
We should develop our natural gas reserves to power our economy, spur manufacturing in the United States and reduce the rate of our carbon emissions. But natural gas is only part of the solution, not the entire solution. Zero-carbon energy sources like nuclear power and renewables should be developed in parallel. They are our best protection against future spikes in gas prices and the impacts of climate change.
Robert McTaggart, Brookings, is an associate professor of physics and coordinator of nuclear education at South Dakota State University.