The vast reserves of US natural gas must be used judiciously to ease the transition to clean energy.
Several years ago, it looked as though the United States was running short of natural gas. Prices spiked as declining production in old fields collided with increasing industrial demand. Electric utilities shifted from 'clean' gas back to cheap coal, and suppliers began building terminals to import liquefied natural gas from abroad. Yet today, coal-fired power is again on the wane, ports for liquefied natural gas are idling below capacity, and the nation is awash with gas.
So what happened? Clearly, the threat of carbon regulation has curbed industry's appetite for coal, and the sagging economy has depressed energy demand across the board. But just as importantly, natural-gas production is again on the rise. Thanks to advances in drilling technology, including horizontal drilling and more effective rock fracturing, producers have at last unlocked the vast quantities of gas trapped underground in impermeable strata of shale.
The Potential Gas Committee, a volunteer group of industry, government and academic experts headquartered in Golden, Colorado, increased its estimate of recoverable gas reserves by 39% in its biennial report released last month, mostly because of shale gas. The new total, almost 60 trillion cubic metres, is equivalent to about a century's worth of gas at current usage rates.
Policy-makers everywhere should take note. Shale formations similar to those that have upended the US natural-gas market exist all over the world. Early explorations are already under way in Canada and several European countries, many of which are overly reliant on coal and politically risky Russian gas imports. And there is no reason to think the development will stop there.
The good news is that natural gas is the cleanest fossil fuel available. Compared with coal, burning gas roughly halves carbon dioxide emissions and eliminates the release of toxic chemicals such as mercury and sulphur dioxide. It is often regarded as a bridge fuel to a low-carbon economy, one that can squeeze out coal and supplement wind and solar energy. Indeed, an abundant and relatively cheap supply of natural gas should spell the end of new coal plants and could to a certain extent allow old coal plants to be replaced.
Deployed without forethought, however, natural gas could hamper the transition to clean energy by outcompeting currently more expensive technologies such as wind and solar. Although natural gas seems clean compared with coal, drilling operations scar the landscape, disturb sensitive ecosystems, increase regional air pollution and may, some fear, pollute groundwater. Then there's the carbon dioxide problem. Building new gas-fired plants would lock in emissions for decades to come — unless they have technologies that would allow the carbon dioxide to be captured and either buried or recycled.
Some have recommended that the United States deploy its newly abundant natural-gas resources in the transportation sector, but that would require vast new infrastructure for what is, in the end, a transition fuel. Congress should avoid such single-shot solutions and keep its eye on the target: a solid greenhouse-gas regulatory programme that sets short- and long-term goals while pricing energy according to the damage it inflicts on the environment.
In the short term, regulators and policy-makers should look for ways to encourage the use of natural-gas plants that are currently fired up only when demand is highest. There is a lot of spare capacity; better to use it wherever possible and retire the dirty, inefficient coal plants that are, in any case, unlikely candidates for the carbon-capture retrofit technologies down the road. But the endgame must bring a halt to greenhouse-gas emissions. From this perspective, power plants that run on gas, like coal, will eventually need carbon-capture technology if they are to remain viable.
It is too early to predict how the natural-gas market will play out, and it would be foolhardy to focus on supply to the detriment of energy efficiency, which should be the top priority. Nonetheless, it seems that the world has much more gas at its disposal than was believed only a few years ago. It should be used wisely.
About this article
Nanopore Surfaces Control the Shale Gas Adsorption via Roughness and Layer-Accumulated Adsorption Potential: A Molecular Dynamics Study
Energy & Fuels (2021)
A new method for assessing stage-based hydraulic fracturing quality in Wolfcamp formation of Permian Basin
Journal of Petroleum Science and Engineering (2020)
Energy Research & Social Science (2017)
Journal of Hazardous, Toxic, and Radioactive Waste (2017)
Applied Energy (2015)